Most Download articles

Published in last 1 year | In last 2 years| In last 3 years| All| Most Downloaded in Recent Month | Most Downloaded in Recent Year|

In last 3 years

Please wait a minute...


For Selected: Download Citations EndNote Ris BibTeX Toggle Thumbnails

Select

Research review in regulating interfacial interaction on MOF-based mixed matrix membranes for gas separation Lili GONG Ju BAI Can WANG Wei LAI Linglong SHAN Shuangjiang LUO Zhichang LIU The Chinese Journal of Process Engineering    2023, 23 (4): 489-500.   DOI: 10.12034/j.issn.1009-606X.223054 Abstract （1129）   HTML （38）    PDF （7406KB）（4025）       Knowledge map    Save Mixed matrix membranes (MMMs) have attracted substantial attention for gas separation, combining the advantages of organic polymers and inorganic fillers, which are expected to solve the Trade-off effect. Metal organic frameworks (MOF), as a kind of innovative filler, provided promising development opportunities for MMMs, thanks to high surface area and porosity, adjustable pores, and low density, etc. These unique physical and chemical properties promoted the application in gas adsorption, separation, and storage. MOF is regarded as good compatibility with the polymer matrix because the organic linkers in MOF are more similar to the organic chain of the polymer compared with traditional inorganic materials (molecular sieve or metal oxide, etc.). Gas separation performance is improved by incorporating MOF into the polymer matrix, which is expected to balance the Trade-off effect. However, the separation performance of MMMs is not simply the sum of the two phases and is far below the predicted theoretical value by the material simulation in most cases. One of the key reasons for these non-ideal morphologies resulting from poor interfacial compatibility, including the non-selective interfacial voids, polymer rigidified, and pore blockage, which reduce the separation performance of MMMs. Therefore, good interfacial compatibility plays a key role in MMMs. Constructing effective interface interactions is a feasible strategy to improve interface compatibility. Thus, in this review, a comprehensive overview of the main technical challenges in developing MOF-based MMMs and a detailed description of the interface issues are provided. And constructing different interface interactions, including hydrogen bonds, covalent bonds, coordination bonds and others, has been expounded through various methods and strategies in the last five years. Finally, it aims to summarize the positive effects on the properties of MMMs through effective and strong interface interactions, guiding the future development of MOF-based MMMs. Related Articles | Metrics

Select

Review of additives for electrolyte of sodium-ion battery Yuyue GUO Xiaoying ZHAI Ningbo ZHANG The Chinese Journal of Process Engineering    2023, 23 (8): 1089-1101.   DOI: 10.12034/j.issn.1009-606X.223104 Abstract （1762）   HTML （84）    PDF （3494KB）（1764）       Knowledge map    Save With the upsurge of the energy revolution, secondary battery as a new way of energy storage has been widely concerned owing to their efficient energy conversion. As we all know, lithium-ion batteries (LIBs) have high operating voltage and high energy density, they can be used in various application scenarios, such as electrical vehicles (EV), portable electronic devices, and large-scale energy storage systems. However, due to the shortage of lithium resources and rising prices of raw materials, many battery companies are observed to undergo cost pressure and bankruptcy risk. Given this, sodium-ion batteries (SIBs) work similarly to lithium-ion batteries, but they have great advantages in terms of resource reserve, low cost, low temperature, rate performance, and safety, thus have received strong attention from researchers and engineers. In the sodium-ion battery system, it is also composed of the positive electrode, negative electrode, electrolyte, separator, and other key components. The electrolyte, as the intermediate bridge connecting the positive and negative electrode material system, plays a vital role to undertake the transport of sodium ions, which mainly consists of organic solvent, sodium salt, and additives. The introduction of a small number of functional additives can significantly improve the overall performance of the battery because it constructs a solid electrolyte interface (SEI) between electrolyte and electrode. Different kinds of additives can exhibit specific properties to meet different conditions. This review focuses on the use of electrolyte additives, including unsaturated carbonates, sulfur compounds, phosphorus compounds, silicon compounds, inorganic sodium salts, and other types of components. Meanwhile, the research progress and related mechanisms of this addition agent in the electrolyte of sodium-ion batteries in recent years were summarized as a reference for subsequent research. Finally, the future study of electrolyte additives prospects from the science idea and practical application, for example, density functional theory, AI for science, and in-situ analysis method for SIBs. Related Articles | Metrics

Select

CO2 methanation: recent advances in catalyst development and reaction mechanistic study Junbo TIAN Fangna GU Fabing SU Zhanguo ZHANG Guangwen XU The Chinese Journal of Process Engineering    2023, 23 (3): 375-395.   DOI: 10.12034/j.issn.1009-606X.222027 Abstract （2511）   HTML （116）    PDF （12772KB）（1166）       Knowledge map    Save Choosing a suitable approach for CO2 utilization is crucial to achieving carbon neutrality and carbon peak goals as early as possible. Synthesis of synthetic natural gas (SNG) by methanation of CO2 using hydrogen produced from renewable energy is widely regarded as an efficient and promising carbon capture and utilization technology, which is expected to realize carbon recycling. Considering the importance of CO2 methanation, we provide a systematic review of the latest studies. Firstly, the effect of different reaction conditions on CO2 methanation is introduced from the perspective of thermodynamics. Secondly, the research progress of CO2 methanation catalysts is reviewed from four aspects: active metal, support, preparation method, and assistive technology. In detail, the active components are classified into cheap metal-based (Ni, Fe, Co, and Mo) and noble metal-based (Ru, Rh, Pt, and Pd) materials, and the supports are divided into the conventional oxides (Al2O3, SiO2, TiO2, ZrO2, and CeO2) and the supports with novel structures (e.g., metal-organic frameworks and carbon-based materials), which are all discussed and evaluated in depth. The preparation methods of catalyst are classified as the conventional ones (such as impregnation, coprecipitation, hydrothermal, sol-gel, and solid-phase synthesis) and unconventional ones. The latter includes three technologies such as ultrasound, microwave, and plasma, which can speed up the synthesis and reaction process and facilitate the high dispersion of the active components on the supports. Subsequently, two reaction mechanisms in CO2 methanation (the formate and CO pathways) are discussed. The specific reaction pathway for CO2 methanation is related to the properties of the catalyst surface (e.g., hydroxyl abundance, adsorbed O2- sites) and the reaction conditions (e.g., reaction temperature and pressure). Finally, current research challenges are put forward, and the prospects for future research in this area are made. Related Articles | Metrics

Select

Research progress in the preparation of porous biomass carbon materials and their applications in supercapacitors Xuemin ZHANG Guanyu HE Shaoqi YIN Tingting HUANG Jinping LI Jian ZHENG The Chinese Journal of Process Engineering    2024, 24 (2): 127-138.   DOI: 10.12034/j.issn.1009-606X.223036 Abstract （1635）   HTML （70）    PDF （1013KB）（766）       Knowledge map    Save The biomass carbon material is a kind of green and renewable energy material. Its efficient utilization is of great significance for the sustainable development of the energy environment and the green and low-carbon transition of energy. Biomass carbon materials are widely used in energy storage and conversion, catalysis, adsorption, and many other fields due to their porous nature, abundant functional groups, large specific surface area, excellent electrochemical performance, low cost, and renewable. However, the properties of biomass carbon materials are not only closely related to the microstructure, but also the heteroatom doping has an important impact on the structure and electrochemical properties of biomass carbon materials. The accurate structure regulation of biomass carbon materials is an effective way to improve their electrochemical performance. In this work, the preparation methods of biomass carbon materials and their applications in supercapacitors are comprehensively reviewed, and the relationship between the structure and properties of porous carbon materials is discussed. On this basis, the influence mechanism and rules of different conditions, and different preparation processes (such as material selection, material treatment, and activation mode) on the structure characteristics of biomass carbon materials are analyzed. In this review, the mechanism and rules of the influence of the structure characteristics on the electrochemical properties of porous biomass carbon materials are described in detail, and the preparation process and performance regulation of porous biomass carbon materials need to be perfected and improved. Finally, the main development directions of preparation technology and electrochemical properties of porous biomass carbon materials in the future are pointed out. Related Articles | Metrics

Select

Advances in biosynthesis of diamine as core monomers of new nylon materials Kun LIN Zhuang LI Kun WANG Ying BI Xiuling JI Zhigang ZHANG Yuhong HUANG The Chinese Journal of Process Engineering    2023, 23 (7): 958-971.   DOI: 10.12034/j.issn.1009-606X.223147 Abstract （1193）   HTML （36）    PDF （1140KB）（714）       Knowledge map    Save In the context of carbon neutrality, bio-diamine synthesis is an effective way to achieve the low-carbon production and sustainable development. Using synthetic biology, metabolic engineering, protein engineering strategies, we are able to design and construct efficient key enzymes and pathways for the biosynthesis of diamines. In this work, the progress of diamine synthesis is reviewed around two synthetic strategies: microbial de novo fermentation and whole-cell catalysis. The main diamines include 1,4-butanediamine, 1,5-pentanediamine, and 1,6-hexamethylenediamine. The biosynthesis of butanediamine mainly includes ornithine decarboxylation and lysine decarboxylation pathways, and butanediamine is mainly produced by fermentation. However, the current yield of butanediamine is low and cannot meet the requirments of industrial production. The biosynthesis of pentanediamine depends on the decarbosylation of L-lysine, mainly by de novo fermentation and whole-cell catalysis. The whole-cell catalysis for pentanediamine is more efficient, which has been widely used in large-scale production with the maturity of the technology. Hexamethylenediamine is currently synthesized by constructing artificial pathways. In addition, to address the challenges encountered in the biosynthesis of diamines, such as many by-products, poor strain activity, low yield, difficult separation, and purification, we proposed methods to improve the biosynthesis of diamines by combining metabolic engineering and protein engineering to optimize key enzyme catalysis, exploring the mechanism of cell damage caused by diamine accumulation, enhancing the specificity and activity of enzyme catalysis to improve production intensity, and optimizing the fermentation system to simplify the subsequent separation and purification steps. Finally, we foresee the future direction and development prospect of diamine biosynthesis. Related Articles | Metrics

Select

Cover and Contents The Chinese Journal of Process Engineering    2023, 23 (9): 0-.   Abstract （185）      PDF （4613KB）（706）       Knowledge map    Save Related Articles | Metrics

Select

Theoretical design of new energy solid-state battery materials and development of battery technology under the background of carbon peaking and carbon neutrality Hongjie XU Guanghui WANG Yujie SU Zhigao ZHANG Haitong LI Zhongzheng YANG Yuchen WANG Linyue HU Guoqin CAO The Chinese Journal of Process Engineering    2023, 23 (7): 943-957.   DOI: 10.12034/j.issn.1009-606X.223113 Abstract （700）   HTML （19）    PDF （4779KB）（683）       Knowledge map    Save Rechargeable lithium metal batteries (LMBs) have attracted wide attention due to their high theoretical energy density and important applications in portable electronic devices, electric vehicles, and smart grids. However, the implementation of LMBs in practice still faces many challenges, such as low Coulombic efficiency, poor cycle performance, and complex interfacial reactions. An in-depth analysis of the physical basis and chemical science of solid-state batteries is of great significance for battery development. To confirm and supplement the experimental research mechanism, theoretical calculation provides strong support for exploring the thermodynamic and kinetic behavior of battery materials and their interfaces and lays a theoretical foundation for designing batteries with better comprehensive performance. In this review, the theoretical and structural design ideas of the Li10GeP2S12 system and argyrodite system in sulfide solid electrolytes are reviewed, including the transport mechanism and diffusion path of lithium ions. The theoretical design ideas of new anti-perovskite Li3OCl and double anti-perovskite Li6OSI2 electrolyte systems are analyzed. The transport mechanism of Li+ in oxide solid electrolyte systems under defect regulation is reviewed. In addition, the theoretical design of new halide electrolyte systems, and the role of computational materials science in the study of battery material properties are also introduced. The key issues such as ion transport mechanism, phase stability, voltage platform, chemical and electrochemical stability, the interface buffer layer, and electrode/electrolyte interface are analyzed by theoretical methods. Understanding the charge-discharge mechanism at the atomic scale and providing reasonable design strategies for electrode materials and electrolytes. Related Articles | Metrics

Select

Study of effect of montmorillonite on distribution of pyrolysis products of oil shale kerogen based on molecular dynamics simulation Xiang LI Jinhui ZHAN Guangwen XU The Chinese Journal of Process Engineering    2023, 23 (5): 724-733.   DOI: 10.12034/j.issn.1009-606X.222140 Abstract （348）   HTML （4）    PDF （1185KB）（651）       Knowledge map    Save In this work, based on the molecular dynamics simulation method of reaction force field (ReaxFF), the pyrolysis reaction process of Green River oil shale kerogen in the presence of montmorillonite was studied, and the product distribution of pyrolysis at different temperatures and the characteristics of non-bonding interaction between minerals and organic matter were analyzed. By comparing the product distribution characteristics of the system with montmorillonite and without montmorillonite during the heating process, it showed that montmorillonite had a strong promotion effect on the pyrolysis of kerogen, and lowered the pyrolysis temperature and widened the temperature span of the pyrolysis process, and the presence of montmorillonite resulted the increase of light oil fraction and the decrease of heavy oil fraction in the pyrolysis reaction of kerogen. The results of thermostatic simulations at a range of characteristic temperatures indicated that the addition of montmorillonite increased the yield of small molecular fragments and inhibited the polymerization of large molecular fragments at high temperatures. Montmorillonite for promoting kerogen pyrolysis was initiated by the adsorption effect, which was reflected in the presence of large non-bonding forces between kerogen and montmorillonite, dominated by VDW interactions. The simulation results showed that in contrast to the fragments of C18H30, C18H38, C20H42, C45H60O of kerogen, there were more significant non-bonding interactions between montmorillonite and fragments of C75H118O5N4, C102H167ONS2, C367H550O10N10S2, with the strongest interaction force in the fragment of C367H550O10N10S2 with montmorillonite. Related Articles | Metrics

Select

Research progress in modification of layered oxide cathode materials for sodium-ion batteries Miaomiao LI Xiangyun QIU Yanxin YIN Tao ZHANG Zuoqiang DAI The Chinese Journal of Process Engineering    2023, 23 (6): 799-813.   DOI: 10.12034/j.issn.1009-606X.222296 Abstract （1151）   HTML （118）    PDF （47402KB）（633）       Knowledge map    Save Sodium-ion batteries (SIBs) have been regarded as the major candidate technologies for large-scale energy storage applications due to the rich abundance of Na sources, low cost and safety. And the development of cathode materials also determines the final performances and commercialization. Layered oxide cathode materials have the advantages of high specific capacity, simple structure and good stability. It is one of the most promising sodium cathode materials at present. However, such materials are still faced with irreversible changes in the electrochemical process, unstable storage in air and poor interface stability, which seriously restricts the development of commercialization of SIBs. In order to solve these problems of materials, researchers modified and optimized them. Accordingly, the modification measures of ion doping, surface coating, nanostructure design and P/O mixing and other related modification measures of sodium electric layered oxide cathode materials, which provides a basis for the modification research of sodium electric layered oxide cathode materials are reviewed in this review. Besides, the future development trend of layered oxides is prospected. Related Articles | Metrics

Select

Preparation of nano-calcium carbonate intensified by CO2 micro bubble and transfer-reaction analysis Liheng WANG Xiaoping GUAN Ning YANG Zuze MU The Chinese Journal of Process Engineering    2023, 23 (9): 1313-1324.   DOI: 10.12034/j.issn.1009-606X.222450 Abstract （801）   HTML （9）    PDF （2491KB）（626）       Knowledge map    Save Carbonization is one of the common methods to prepare nano calcium carbonate. Controlling the particle size and particle size distribution of calcium carbonate is the key to the preparation of high-quality nano-calcium carbonate by carbonization. Different operating conditions have different effects on the reaction products. The particle size and size distribution of calcium carbonate can be effectively controlled by controlling different reaction conditions to improve the mass transfer and reaction conditions in the slurry. In batch-operated bubble column reactor, gas flow rate and bubble size are factors affecting mass transfer. This study investigates the influences of operation condition (gas flow rate, initial slurry condition), bubble type (ordinary bubble, micro bubble) on carbonation reaction rate and particle size distribution of calcium carbonate. Furthermore, the effects of bubble type on the stable region and abrupt change region in carbonation reaction process are analyzed. The experimental results show that when using ordinary bubble, the increase of CO2 flow rate accelerates the reaction process and reduces the particle size of calcium carbonate, but it does not affect the time of abrupt change region. With increasing the slurry concentration, the particle size first decreases and then increases in small-diameter column with ordinary bubble. However, when using micro bubble, the particle size of calcium carbonate is significantly reduced, and the time of abrupt change region decreases with the increase of gas flow rate. Moreover, the CO2 flow rate is no longer an influential factor on calcium carbonate particle size, which means that the gas-liquid mass transfer process is not the rate controlling step of carbonation reaction. This study provides some references for studying the application of micro bubbles in calcium carbonate crystallization. Related Articles | Metrics

Select

Preparation and electrochemical properties of Li0.98Ca0.02Mn2O4 Mingsi SHEN Haibo YUAN Doudou ZHANG Jing WANG Gaotian NIU Yangzhou MA Yaxin SUN The Chinese Journal of Process Engineering    2024, 24 (6): 746-752.   DOI: 10.12034/j.issn.1009-606X.223075 Abstract （286）   HTML （9）    PDF （3274KB）（591）       Knowledge map    Save Many research focus on improving the electrochemical properties of LiMn2O4 by chemical doping method. In cubic spinel structure LiMn2O4, the diversity of doping elements and doping positions provides a wide space for improving performance. Doping at the 16d octahedral position occupied by Mn can effectively suppress the Jahn-Teller effect and maintain the stability of the structure. By comparison, using elements with large ion radius to dope at the 8a tetragonal position occupied by Li can enlarge the Li+ diffusion channel and enhance the kinetics diffusion coefficient. In this work, pure phase of Li0.98Ca0.02Mn2O4 was successfully synthesized using the hydrothermal method followed by annealing at 750℃ for 5 h. The crystal structures and the morphologies of the products were analyzed by powder X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). The electrochemical properties were characterized by galvanostatic charge/discharge experiments and electrochemical impedance spectroscope (EIS) tests. XRD analysis showed that the lattice constant increased by 0.12% in Ca-doped LiMn2O4 and the expansion of the crystal cell was beneficial to improving the diffusion of Li+. The small aggregates with porous channels formed by stacking nanoparticles were observed by FESEM. The results showed that Li0.98Ca0.02Mn2O4 exhibited the excellent rate capability with the larger discharge capacity at the relatively current rate range of 0.5 C~5 C. Especially, at 0.5 C, Li0.98Ca0.02Mn2O4 delivered the first discharge capacity of 126 mAh/g, which was 17.8% higher than that of undoped LiMn2O4 samples. The capacity retention of both samples was maintained at about 88.8% after 50 cycles. At 1 C, Li0.98Ca0.02Mn2O4 still holded its high discharge capacity of 117.5 mAh/g and capacity retention of 90% after 50 cycles, 80% after 150 cycles, and 60% after 1000 cycles. Undoped LiMn2O4 sample had low capacity of 57.0 mAh/g, but the capacity retention reacheed 67% after 1000 cycles, indicating good cycle stability. The calculated kinetics diffusion coefficient of Li0.98Ca0.02Mn2O4 was 2.5×10-11 cm2/s, which was about 1.6 times of undoped sample. Related Articles | Metrics

Select

Effect of La content on the microstructure and TiN precipitation behavior of high-titanium steel during slow cooling solidification Yong WAN Chuansheng TANG Guangwei YANG Xuejian ZHANG Yonghong WEN The Chinese Journal of Process Engineering    2024, 24 (7): 852-862.   DOI: 10.12034/j.issn.1009-606X.223309 Abstract （272）   HTML （6）    PDF （9953KB）（553）       Knowledge map    Save In this work, the effects of four kinds of La content on the microstructure and TiN precipitation behavior of high-titanium steel are studied by high temperature melting experiment, optical microscope (OM) and scanning electron microscope (SEM). It is intended to give scientific basis and experimental data for La treatment to refine the size of TiN and the microstructure in the center region of cast ingots of high-titanium steel. The results show that the solidification structures of all experimental steels are equiaxed grains when the solidification cooling rate is 0.17℃/s. La shows obvious ability of deoxidization, S and Al at low La content (0.0013wt%), so LaAlO3 and La2O2S are mainly formed in its steel. La just began to show obvious ability of deoxidization, S and Al at high La content (0.0052wt%, 0.0223wt%). With the consumption of a large amount of O atoms, the deoxidization and sulfur ability of La increased rapidly. Therefore, La2O2S is the predominant precipitate that forms in the steel, and some La2O2S particles will nucleate and grow on the surface of LaAlO3 particles that have previously precipitated. TiN mainly precipitates in the Liquid+δ two-phase region in this experimental steel. LaAlO3 and La2O2S precipitate before TiN, and their small lattice misfit with TiN are the primary cause of their propensity to act as the cores of TiN heterogeneous nucleation. When the La content in the steel is 0wt%, 0.0013wt%, 0.0052wt%, 0.0223wt%, the average axial grain size of each experimental steel is 354, 223, 154, 126 μm, respectively. The maximum size of TiN is 19.1, 11.7, 11.4, 10.4 μm, the TiN area density in each experimental steel is 42.2, 82.9, 86.3, 90.7 No./mm2, the maximum size of TiN is 19.1, 11.7, 11.4, 10.4 μm, and the average size of TiN is 7.8, 4.6, 4.5, 4.4 μm. Related Articles | Metrics

Select

Study on the mechanism of Ni2+ and Mg2+ loss and enhanced separation in sulfuric acid leachate of laterite nickel ore during iron removal using neutralization process Hao JIANG Xin TENG Jun LUO Changye MANG Xinran LI Wenhao SUN The Chinese Journal of Process Engineering    2023, 23 (11): 1558-1567.   DOI: 10.12034/j.issn.1009-606X.223055 Abstract （609）   HTML （9）    PDF （8323KB）（540）       Knowledge map    Save Neutralization precipitation process is often used to remove impurities such as iron, aluminum and chromium from the nickel laterite acid leach solution, however, it accompanied with the loss of nickel and magnesium metal ions. The precipitation behaviors of Ni2+ and Mg2+ ions in nickel laterite acid leach solution during the neutralization precipitation iron removal process was deeply discussed in this work. Furthermore, a novel precipitation mechanism of Ni2+ and Mg2+ with SO42- during the neutralization precipitation iron removal process was proposed. The results showed that under the condition of fixed Ni2+ and Mg2+ concentrations in simulated leachate, the loss rate of Ni2+ and Mg2+ during neutralization and precipitation respectively were 9.13%~23.23% and 9.79%~15.68% with the increase of Fe3+ concentration in simulated leachate. Under the condition of fixed Fe3+ concentrations, the loss rate of Ni2+ and Mg2+ decreased with the increase of the concentration of Ni2+ and Mg2+. According to the results of solution chemical calculation and the characterization of iron hydroxide precipitation by infrared spectroscopy and scanning electron microscopy, both SO42- ions and Fe(OH)3 colloids could co-precipitate in the form of monovalent or binary complex during the neutralization process, in which the lone pair electrons of SO42- in the monovalent complexes bond with Ni2+ and Mg2+ and adsorb, resulting Ni2+ and Mg2+ in the leachate were co-adsorbed with SO42- by Fe(OH)3 colloid and the loss was caused. In addition, it was found that the surfactant such as cetyl trimethylammonium bromide (CTAB), polyethylene glycol (PEG), sodium dodecyl benzenesulfonatecan (SDBS) was added during the neutralization precipitation process can effectively compete for adsorption with neutralizing precipitated products or impede the combination of SO〖_4^(2-)〗 with Ni2+ and Mg2+ ions, which could enhance the selective precipitation of Fe3+ ions during neutralization process. When the dosage of three surfactants was 2×10-5 mol/L, the retention rates of Ni2+ in the process of neutralization and precipitation of iron could reach about 95%, and Mg2+ could reach 100%. Related Articles | Metrics

Select

Research progress on liquid bridge fracture in field of micro-nano technology Zhaofei ZHU Yalong CHU Xianming GAO The Chinese Journal of Process Engineering    2023, 23 (6): 814-825.   DOI: 10.12034/j.issn.1009-606X.222287 Abstract （634）   HTML （18）    PDF （4290KB）（526）       Knowledge map    Save Affected by the scale effect, the morphological characteristics of liquid bridges at the microscale determine the changes in liquid bridge forces that are area-related. Liquid bridge forces have an important impact on the formation and fracture of liquid bridges. The liquid bridge fracture mechanism based on liquid bridge morphology is the theoretical basis of biology, chemistry, materials, micro-nano technology, and many other research fields. At present, the study of liquid bridge fracture is an interdisciplinary discipline involving mathematics, fluid mechanics, interface chemistry, materials science, and other disciplines, however there is few review of the research progress focusing on liquid bridge fracture based on liquid bridge morphology. This review mainly summarizes the fracture theoretical models and experimental methods of axisymmetric liquid bridges, non-axisymmetric liquid bridges, and non-Newtonian liquid bridges. It mainly introduces the weak nonlinear behavior of the fluid generated during the tensile and rupture of the liquid bridge under equilibrium or steady state caused by the forced hydraulic bridge. The influences of key factors such as liquid volume, viscosity, surface tension, wettability, roughness of the solid surface, fracture speed, and liquid bridge morphology on the fracture location or liquid distribution rate of the liquid bridge are systematically described. The experimental methods for quantitatively studying the use of different key parameters affecting liquid bridge fracture are analyzed. The structural characteristics of different experimental apparatus and their advantages and disadvantages are compared and discussed. Furthermore, the innovative and high-value research direction of the research is summarized and proposed, which may be used in future research. Finally, the research frontier trends of liquid bridge fracture in the field of micro-nano technology prospected, and it is pointed out that the future research focused on issues including a more comprehensive hydraulic bridge fracture model, the fracture mechanism, and multi-parameter control method of the liquid bridge. Related Articles | Metrics

Select

Study on curing arsenic-containing compounds and solid wastes by iron-based silicate gel Boyu DU Chao LIU Xing ZHU The Chinese Journal of Process Engineering    2023, 23 (12): 1714-1724.   DOI: 10.12034/j.issn.1009-606X.223085 Abstract （378）   HTML （6）    PDF （2442KB）（524）       Knowledge map    Save During the mining and metallurgy of non-ferrous heavy metals, a large number of arsenic-containing compounds are exposed to the environment, posing great environmental risks to the surrounding water and soil. Due to their good arsenate affinity, iron ions and their compounds are the main components of commonly used chemical arsenic fixation agents. Whether in arsenic pollutant solidification or arsenic-contaminated site remediation, silicate and hydration processes are important physical barriers to arsenic. Based on this, we synthesized an iron-based silicate gel and evaluated its performance for the solidification/stabilization of typical arsenic compounds [Na3AsO4, Ca3(AsO4)2, AlAsO4, and FeAsO4·2H2O] and arsenic-containing sludge from non-ferrous metallurgy, and explored the arsenic fixation mechanism. The results showed that the iron-based silicate gel with a Fe/Si molar ratio of 1:4 could effectively immobilize the arsenic-containing compounds (Na3AsO4 and FeAsO4·2H2O). However, in the process of curing Ca3(AsO4)2 and AlAsO4, due to the competitive reaction between arsenate and silicate, the toxic leaching of arsenic was higher than that in the process of uncaring. The introduction of CaO could inhibit the competitive reaction, improve the arsenic fixation rate of Ca3(AsO4)2 and AlAsO4, and reach more than 98% of the arsenic fixation efficiency. The synergistic effect of Fe and Ca co-precipitation and physical immobilization is responsible for the immobilization/stabilization of arsenic-containing compounds. The core-shell structure with arsenic-containing compounds as the core and iron-based silicate gel/C-S-H gel as the shell separated arsenic species and reduced toxic leaching when in contact with the surrounding environment. The long-term stability showed that the iron-based silicate gel-cured arsenic-containing waste remained highly stable at pH=8 for 30 days. The CaO-assisted iron-based silicate gel proposed in this work showed great potential for the immobilization of arsenic-containing wastes and arsenic-contaminated land and provided a new way to solidify arsenic-containing pollutants. Related Articles | Metrics

Select

Gas-liquid flow simulation of a distillation tray based on OpenFOAM Xiaoqing ZHOU Yunpeng JIAO Tianbo FAN Xianfeng HE Jianhua CHEN The Chinese Journal of Process Engineering    2023, 23 (6): 858-869.   DOI: 10.12034/j.issn.1009-606X.222258 Abstract （607）   HTML （15）    PDF （8891KB）（513）       Knowledge map    Save Distillation column with sieve tray is an important separation equipment and widely used in the process industry. The complex behavior of the gas-liquid two-phase flow in distillation columns, especially on the tray, significantly affects the separation performance. With increasing applications of the CFD simulation in multiphase flow, it is interesting to adopt the CFD tools in distillation design and optimization. Traditionally, commercial CFD software has been applied in this field, while they face the problems of black-box feature, limited and expensive license, inflexibility of developing tailored models, etc. Therefore, this work turns to the open source platform of OpenFOAM. By using the Eulerian solver in OpenFOAM, an experimental sieve tray column is studied. The two-phase flow characteristics under different operating conditions are explored, including the height of the clear liquid layer, the gas and liquid velocity, the pressure drop, etc. The predicted trends are consistent with the experimental results. The simulated clear liquid height decreases with increasing gas flow rate and increases with liquid flow rate, and its deviation from the experiments is attributed to the empirical drag correlations which need further study. The influences of sieve holes and liquid inlet conditions on the liquid velocity distribution have been studied. It is found that the number of sieve holes has little impact, and simulations with non-uniform liquid inlet conditions agree with the experiments better. This study verifies the feasibility of using OpenFOAM to simulate distillation columns. The next step is to apply the mesoscale approach to gas-liquid crossing flow systems, construct a new interphase drag model to improve the accuracy of the simulation, and consider the influence of heat and mass transfer on the flow field. This work lays a foundation for the next-step coupling simulations, which is promising for the design and optimization of distillation columns. Related Articles | Metrics

Select

Research progress of thermal management technology for lithium-ion batteries Jiaxin LI Pengzhao LI Miao WANG Chun CHEN Liangyu YAN Yue GAO Shengchen YANG Manman CHEN Cai ZHAO Jing MAO The Chinese Journal of Process Engineering    2023, 23 (8): 1102-1117.   DOI: 10.12034/j.issn.1009-606X.223094 Abstract （1388）   HTML （64）    PDF （13593KB）（513）       Knowledge map    Save Efficient battery thermal management technology is critical to the safe operation, long cycle life, and overall cost reduction of lithium-ion batteries and is important in promoting the large-scale application of lithium-ion batteries. In this review, several mainstream battery thermal management technologies are discussed in detail, including air cooling, liquid cooling, new phase change material cooling, and thermoelectric cooling technology. The battery heat generation model is briefly described. Finally, the development direction of battery cooling technology is prospected. Air cooling technology is simple in structure, but it is difficult to ensure temperature uniformity of the cells within the battery pack and is not suitable for cooling large lithium-ion battery packs, but is more suitable for small flying electric devices and low-end electric vehicles. Cooling plate liquid cooling technology is more effective, but there is a risk of coolant leakage and the temperature uniformity needs to be further improved. Immersion liquid cooling technology offers significant cooling and temperature uniformity but is expensive and is likely to be used more often in the future in energy storage plants with high cooling requirements, while for most lithium-ion electric vehicles the lower-cost cooling plate liquid cooling technology is more suitable. Phase change material cooling and thermoelectric cooling technologies without moving parts have achieved initial commercial application in electronic equipment and small power plants, but the cooling efficiency is low and needs further refinement. It is worth noting that it is critical to choose the right cooling technology for the user's needs. While there is no perfect cooling solution, a combination of cooling technologies can be used to meet the thermal management needs of a wider range of application scenarios. Related Articles | Metrics

Select

Machine learning and process modeling of high moisture biomass gasification in downdraft gasifier Fenglei QI Zhen WANG Guoqing LU Xiaohao LIU Qi DANG Peiyong MA The Chinese Journal of Process Engineering    2024, 24 (1): 87-96.   DOI: 10.12034/j.issn.1009-606X.223114 Abstract （555）   HTML （10）    PDF （4384KB）（510）       Knowledge map    Save Biomass gasification is a potential pathway for thermochemically generating renewable producer gas, which serves as a good substitute fuel in heating and electricity section and is beneficial to the reduction of greenhouse gas emission. Biomass feedstock varies significantly in its composition, especially the content of moisture, posing a challenge for biomass gasification process design and operation in practice, however few research were carried out to elucidate the gasification principles of biomass with different moisture content. In this research, the effects of moisture content and process parameters on biomass gasification characteristics including syngas quality and energy balance are investigated by adopting machine learning and process modeling approaches. The prediction accuracy of the two approaches is first validated by comparing with experimental data. The obtained results indicate that the moisture content of biomass has a great negative impact on the low heating value (LHV) of produced gas, but does not significantly affect the carbon conversion efficiency (CCE) in the downdraft gasifier. The LHV of the produced gas decreases when the air equivalence rate (ER) increases due to the increment of carbon dioxide in the producer gas, but CCE increases with the increase of ER. The energy balance analysis suggests that ER increase with the increment of moisture content in biomass in order to maintain energy balance of the system. Pretreatment of biomass by drying is favorable to maintaining the quality of syngas, but the tradeoff is to consume a certain amount of producer gas to supply heat for the drying process. The consumption rate of the producer gas increases as the moisture content of biomass goes up, which is characterized by a nearly linear increase with the moisture content in the range of 20wt%~60wt% and an exponentially increment as the moisture content goes up beyond 60wt%. The current research provides fundamental insights on gasification characteristics of biomass with different moisture contents. Related Articles | Metrics

Select

Research progress on molding process of catalysts for fixed bed reactor Shanshan LIU Qida DING Tao GUO Yaofeng WANG Baohua XU The Chinese Journal of Process Engineering    2023, 23 (4): 501-511.   DOI: 10.12034/j.issn.1009-606X.222088 Abstract （892）   HTML （32）    PDF （1464KB）（496）       Knowledge map    Save The progresses obtained in the catalytic technology are driven by the social demands, such as environment, energy, chemicals, and fuels. The ultimate goal is to increase the process efficiency for scale-up. The molding catalysts are usually multicomponent material of millimetre-size consisting of the active phases, supports, and various molding additives suitable for commercial applications. Different from the powder catalysts, the molding catalysts should not only possess the catalytic activity of the powder catalyst but also consider the use of binder, lubricant, acid and pore-forming agent to satisfy the required mechanical strength and chemical stability to ensure that they can run smoothly and have a long life in industrial reactors. In addition, the shape and size of the molding catalysts affect the catalytic performance by affecting the flow state of the materials inside the reactor. Therefore, the molding process is complex and full of challenges. This review introduces the influence of molding conditions on both the mechanical and the catalytic properties at the fixed bed. Specifically, the effects of the types and amounts of additives, the addition sequence, the calcination conditions, the pulp ratio, and the shape and size of molding catalysts are focused. Weibull modulus can be used to measure the reliability of mechanical strength of brittle materials, and further judge and predict the reliability of catalyst strength value. In addition, this review also introduces the application of Weibull distribution in the reliability judgment and prediction of catalyst strength value, and the progress of computational fluid dynamics (CFD) simulation in assisting catalyst morphology design. The potential of Weibull distribution and CFD in future applications of molding catalyst are pointed out. Related Articles | Metrics

Select

Research progress of core monomer separation and purification technology for bio-based materials Kun WANG Xiuling JI Kun LIN Yuhong HUANG The Chinese Journal of Process Engineering    2023, 23 (8): 1137-1149.   DOI: 10.12034/j.issn.1009-606X.222314 Abstract （628）   HTML （19）    PDF （2738KB）（484）       Knowledge map    Save The production of petrochemical-based materials consumes large amounts of non-renewable resources and cause a certain degree of pollution to the environment. The performance of bio-based materials produced by renewable resources can be comparable to that of petrochemical based materials, which is in line with the development concept of green, low-carbon and environmental protection, and provides strong technical support for the realization of the goal of carbon peaking and carbon neutrality. In recent years, with the domestic and international policies tilted to the bio-based materials industry, bio-based materials have become a new material for domestic and international development, providing a good opportunity for the development of bio-based materials industry. The core monomer of bio-based materials produced by biological method has the advantages of mild production conditions, low price, and green environmental protection. But the complex composition within the fermentation broth as well as the low concentration of monomers and the difficulty of separation have seriously restricted the development of the whole industry of bio-based materials. The production of bio-based materials requires high-purity monomers, and a small amount of impurities affect the appearance and performance of bio-based materials. The existing research and application of separation of core monomers of bio-based materials has developed the process of obtaining high purity separation and purification of core monomers of bio-based materials by taking full advantage of chemical separation technology. This review briefly introduces the current status of the production of bio-based materials, reviews the research progress of several widely used separation and purification technologies for core monomers of bio-based materials in recent years, analyzes the advantages and disadvantages of current separation technologies. Finally providing an outlook on the development trend of separation and purification technologies for core monomers of bio-based materials. Related Articles | Metrics

Select

Design of temperature control system for evaporator based on cascade fuzzy self-adaptive PID method Jun SUN Dian ZHANG Qingshan HUANG Liang TIAN Tianqi CHANG Qi LIU The Chinese Journal of Process Engineering    2023, 23 (9): 1290-1299.   DOI: 10.12034/j.issn.1009-606X.222320 Abstract （534）   HTML （16）    PDF （1561KB）（469）       Knowledge map    Save It has been widely accepted that applying the traditional control method is difficult to achieve precise temperature control of the evaporator because the evaporator temperature has nonlinear, time-varying characteristics with a significant lag. Based on the evaporator production process analysis, an evaporator temperature control method based on the cascade fuzzy adaptive proportional-integral-differential (PID) is proposed here, which combines the fuzzy control theory with the cascade PID control theory to set up a Continuous Function Charts (CFC) configuration of fuzzy adaptive PID control for the main loop and the secondary loop. A real-time self-adapting amendment of PID parameters in the main loop and the secondary loop during the evaporator temperature control can be realized using this control strategy. The experimental results with the SMPT-1000 simulation equipment and Siemens PCS7 process control system show that after the real-time self-adapting amendment of PID parameters, the computed new proportional parameter can successfully accelerate the response speed of the system, the calculated new integral parameter can efficiently reduce the deviation of the system, and the deduced new differential parameter can wisely play an essential role in the anticipatory control. The corresponding experimental results demonstrated that the adjustment time of temperature response could be shortened by one-half, and the maximum deviation could be reduced by more than four-fifths. Additionally, the adjustment time of the temperature rise load could be shrunk by more than three-fifths, and the maximum deviation could be decreased by more than four-fifths. Moreover, the recovery time for the superheated steam perturbation could be narrowed by more than one-half, and the deviation of minimum and maximum temperature could be condensed by more than one-tenth. It is noteworthy that compared with the traditional cascade PID control method, the cascade fuzzy self-adaptive PID control strategy proposed here has the notable advantages of short regulation time, slight overshoot, and good robustness, which can overcome the shortcomings of the traditional cascade PID control method and provide an effective way and mathematical models to solve the problem of accurate temperature control in the evaporator. Therefore, the control strategy developed here has a particular significance in ensuring the smooth operation of the evaporator. Related Articles | Metrics

Select

Research progress of lithium polysulfide capture in lithium-sulfur batteries Tingting HU Haijian LIU Yunyi CHEN Lingli LIU Chun'ai DAI Yongsheng HAN The Chinese Journal of Process Engineering    2023, 23 (9): 1231-1243.   DOI: 10.12034/j.issn.1009-606X.222413 Abstract （608）   HTML （27）    PDF （6063KB）（463）       Knowledge map    Save Lithium-sulfur battery has an ultra-high theoretical specific capacity (1675 mAh/g) and theoretical specific energy (2600 Wh/kg), which is far higher than commercial secondary batteries. In addition, the sulfur element is rich in the earth, and its price is cheap, the extraction process is environmentally friendly. Therefore, a lithium-sulfur battery is considered as an ideal energy storage unit for the future energy storage system. However, the lithium polysulfide intermediates generated in the charging and discharging process are easily soluble in the electrolyte, resulting in a loss of active materials and an increase in the electrolyte viscosity. In addition, the dissolved lithium polysulfide is inclined to migrate between positive and negative electrodes, and reacts with the lithium negative electrode, causing irreversible loss of active substance sulfur, greatly reducing the battery life and safety. This phenomenon is called the shuttle effect, which hinders the commercialization process of lithium-sulfur batteries. In recent years, researchers have attempted to solve this problem through physical adsorption, chemical action, and external field constraint, and achieved impressive progress. This work summarizes the research progress of capturing lithium polysulfide, and compares the characteristics of each approach and its impact on the electrochemical performance of lithium-sulfur batteries. Whether it is the physical constraint of the porous structure of carbon materials, the chemical interaction between the carrier materials and lithium polysulfide, or the adsorption of electric and magnetic fields on lithium polysulfide, lithium polysulfide is fixed on the positive side and to inhibit its dissolution and diffusion to the negative electrode. Capturing lithium polysulfide by external magnetic field, internal magnetic field induced by magnetic particles, and internal electric field generated by spontaneous polarization of ferroelectric materials is also highlighted. Finally, the challenges in capturing lithium polysulfide and the possible solution are prospected. Related Articles | Metrics

Select

Progress on resource utilization and second utilization of chloride removal products from Friedel's salt precipitation method Yun GU Peng CHU Dongdong GE Shouqiang HUANG Min JIANG Hongying LÜ Wenxin ZHANG Yangyang LÜ Yang LÜ Yaheng ZHANG The Chinese Journal of Process Engineering    2024, 24 (2): 151-161.   DOI: 10.12034/j.issn.1009-606X.223122 Abstract （786）   HTML （22）    PDF （1474KB）（453）       Knowledge map    Save The high concentration of Cl- in wastewater can seriously corrode industrial equipment, and also pollute the water environment. A series of technologies for removing Cl- from wastewater have been reported, such as membrane separation, concentration, evaporation crystallization, chemical precipitation, adsorption, ion exchange, electrolysis, oxidation, and solvent extraction. Among them, chemical precipitation has significant advantages in equipment investment and operability, Friedel's salt precipitation method of Cl- removal has been intensively studied because of the wide source and low price of raw materials, compared with other methods using silver, copper, or bismuth. After the Cl- removal, a large quantity of chemical sludge is produced, which mainly contains Friedel's salt (3CaO?Al2O3?CaCl2?10H2O), katoite [Ca3Al2(OH)12], and calcium hydroxide, etc. Due to the complex components and the tight binding of Cl- in the interlayer spacing of Friedel's salt, the resultant sludge is difficult to recycle. To promote the application of Friedel's salt precipitation method, it is very important to utilize its Cl- removal products, especially Friedel's salt, as a resource. Based on the introduction of the compositional and structural characteristics of Friedel's salt, this work highlights the advantages of Friedel's salt precipitation method, which cannot only remove Cl-, but also obtain Friedel's salt, by comparing other preparation methods. According to the aluminum and calcium components of Friedel's salt and its layered bimetallic hydroxide structure, effective resource utilization can be carried out, including the removal of various heavy metal cations (i.e., Cu2+, Cd2+, Co2+, Zn2+, and Pb2+) and oxygenated anion complexes [i.e., Sb(OH)6-, AsO43-, SeO42-, and CrO42-], and the preparation of polyaluminum chloride coagulants and as sludge dewatering regulators, etc. These uses have broad application prospects, providing reference and exploration direction for the further development of Friedel's salt precipitation method. Related Articles | Metrics

Select

Preparation of sodium bicarbonate modified biochar and analysis of its adsorption mechanism for carbamazepine in water Jihuan ZHANG Jinwei ZHANG Wenlong WU Siqiang Lin Yan LI Lei DING The Chinese Journal of Process Engineering    2024, 24 (9): 1106-1119.   DOI: 10.12034/j.issn.1009-606X.223363 Abstract （425）   HTML （23）    PDF （2886KB）（453）       Knowledge map    Save This study used agricultural waste silk gourd complex powder as raw material and sodium bicarbonate as activator to prepare sodium bicarbonate modified biochar (SBC) that can efficiently adsorb carbamazepine (CBZ) in water through impregnation pyrolysis method. The physical and chemical characteristics such as surface morphology, pore size distribution, functional groups, and degree of graphitization are analyzed through characterization methods. The effects of temperature, dosage, pH and other factors on the adsorption of CBZ in water by SBC are studied through batch experiments. The results show that compared to the original biochar (BC), SBC has a higher specific surface area of 531.43 m2/g and a richer pore size structure. The effect of pH on the adsorption of CBZ by SBC is minimal, and SBC is almost unable to adsorb large molecular humic acids. The Sips model can better describe the adsorption equilibrium law of CBZ on SBC, with an adsorption capacity of 125.52 mg/g at 298 K. Thermodynamic analysis shows that the adsorption of CBZ by SBC is a spontaneous endothermic process, with physical adsorption being the main process. By analyzing the energy distribution of SBC sites and density functional theory, the enhanced adsorption mechanism of CBZ on SBC is further explored. The results show that hydrogen bonding, π-π electron acceptor donor, and pore filling are involved in the process of SBC adsorption of CBZ. Methanol can effectively regenerate saturated SBC, and after four adsorption desorption cycles, the adsorption capacity of SBC for CBZ remains at 68.132 mg/g. This article uses agricultural and forestry waste sponge gourd as a carbon source to prepare biochar for removing pollutants from water, providing a feasible approach to simultaneously achieve the resource utilization of agricultural waste and reduce environmental pollution. Related Articles | Metrics

Select

Research progress of microreactor technology in gas-liquid two-phase flow systems Xinran YE Zan WU Haiou WANG Jianren FAN The Chinese Journal of Process Engineering    2024, 24 (9): 1001-1015.   DOI: 10.12034/j.issn.1009-606X.224035 Abstract （738）   HTML （26）    PDF （3984KB）（428）       Knowledge map    Save Microreactors possess advantages such as high heat and mass transfer efficiency, strict control of reaction parameters, ease of scale-up, and good safety performance, and hold promises for enabling and accelerating the discovery of flow chemistry towards highly efficient and more sustainable chemical synthesis. Gas-liquid multiphase catalytic reaction is commonly encountered in chemical production process, where the reaction stream enters the microfluidic channel in a continuous flow and undergoes rapid reaction. The combination of microreactor technology and gas-liquid multiphase catalytic reaction facilitates the development of efficient and sustainable chemical production techniques. Gas-liquid multiphase catalytic microreactors can be classified as wall-coated or filled-bed microreactors based on catalyst fixation approaches. By optimizing the geometric structure design of the microreactor, it is possible to further reduce the reaction time, minimize the material retention and suppress the occurrence of undesirable reactions, thus improving the microreactor performance. However, the optimization of microreactor structure requires a comprehensive understanding of various physics including the flow characteristics of gas-liquid fluids, the mass transfer mechanism and reaction kinetics within the microreactor. Both the flow pattern and mass transfer of multiphase fluids in microreactors will affect the reactor performance. Investigating the gas-liquid system in microreactors promotes improved design of practical devices. This review mainly summarizes typical gas-liquid microreactor examples, and hope to provide inspiration and guidance for the design, fabrication, and application of microreactors. The review is organized as follows, first, the features of microreactor technology are introduced and the optimization strategies for microreactor structures are presented, which is followed by a detailed discussion on the flow patterns, mass transfer characteristics and bubble breakup dynamics in gas-liquid multiphase systems within microreactors. Then, examples of multiphase catalytic microreactors in applications (mainly focusing on wall-coated microreactors and filled-bed microreactors) and their limitations are introduced. Finally, the research trends and application prospects in gas-liquid multiphase microreactors are envisaged. Related Articles | Metrics

Select

Effect of oxygen-rich combustion conditions on heating process of slab in reheating furnace Biao LU Xingyin WANG Qingyun HU Yan CHEN Demin CHEN Jin GAO The Chinese Journal of Process Engineering    2024, 24 (7): 805-814.   DOI: 10.12034/j.issn.1009-606X.223306 Abstract （336）   HTML （5）    PDF （4324KB）（421）       Knowledge map    Save Compared with traditional air combustion, oxygen-enriched combustion can increase the flame temperature, strengthen the radiation heat transfer in the furnace, reduce the exhaust heat loss, increase the volume fraction of CO2 in the flue gas, and is conducive to CO2 capture, so it has become a hot spot in the field of industrial furnace research. At present, most studies simply transform the whole heating furnace from conventional air combustion to oxygen-rich air combustion, and are limited to the single factor of oxygen volume fraction. In order to explore the influence of different oxygen-rich combustion arrangement forms and different oxygen volume fractions on the heating furnace thermal characteristics and slab heating process, two oxygen-rich combustion models (JC-1 and JC-2) with oxygen volume fraction of 21vol%~49vol% are established to study the effects of combustion of gas and fuel on the thermal characteristics of the furnace and slab heating characteristics by numerical simulation. The results show that compared with the JC-1 condition, the temperature distribution in the furnace under JC-2 condition is more uniform and the slab temperature is higher, so the oxygen-rich combustion arrangement under JC-2 condition is better than that under JC-1 condition. Slab temperature and furnace thermal efficiency increase with the increase of oxygen enrichment volume fraction, but the increase rate decreases gradually. When the oxygen volume fraction is between 21vol% and 37vol%, the heating furnace slab temperature and furnace thermal efficiency increase at a higher rate. In this volume fraction range, when the oxygen volume fraction of JC-1 and JC-2 increases by 1%, the furnace thermal efficiency increases by 0.44% and 0.47%, and the energy saving rate increases by 1.07% and 1.12%, respectively. Therefore, 37vol% is the optimal oxygen volume fraction for oxygen-enriched combustion. The significance of this study is to provide reference for the existing reheating furnace to implement the transformation of oxygen-rich combustion. Related Articles | Metrics

Select

Research progress on desulfurization technology for blast furnace gas Xindong WANG Tingyu ZHU Yuran LI The Chinese Journal of Process Engineering    2023, 23 (7): 1003-1012.   DOI: 10.12034/j.issn.1009-606X.222334 Abstract （661）   HTML （22）    PDF （1011KB）（414）       Knowledge map    Save The desulfurization technology for blast furnace gas as a source of emission reduction technology is of great significance to promoting ultra-low emission for the whole process in the iron-steel industry. The sulfur-containing components in the blast furnace gas are mainly organic sulfur, coexisting with other complex components. This work discusses the emission limits of sulfur-containing components in various occurrence forms (SO2, H2S, and S), and analyzes their transformation relationship through the mass balance of sulfur. The bottleneck of desulfurization technology for blast furnace gas is to remove the carbonyl sulfur (COS). The aluminum-based catalyst and carbon-based catalyst used for COS catalytic hydrolysis are analyzed in detail, in which γ-Al2O3 is both a carrier and an active component, and activated carbon has the functions of catalyst and adsorbent. The effect mechanism of the complex components O2, and Cl- on the deactivation of hydrolysis catalyst is further elucidated due to the formation of deposition products. For the gaseous H2S formed after the COS hydrolysis, the two kinds of wet removal technology, mainly including the chemical absorption method and catalytic oxidation method, are compared in the reaction mechanism, desulfurizer and product. The difference among the zinc oxide, iron oxide, and activated carbon adsorbent used in the dry removal technology is also concretely elaborated in the reaction mechanism, sulfur capacity, and temperature adaptability. In view of the integrated adsorption of organic sulfur and inorganic sulfur, molecular sieve adsorbent is briefly described in the selective adsorption principle and regeneration process. The "hydrolysis+wet", "hydrolysis+dry", and integrated removal processes have been explored and applied currently, which are preliminarily evaluated. Finally, it is pointed out that the research and development of desulfurization technology focus on how to improve the activity of the hydrolysis catalyst and reduce the influence of complex components in blast furnace gas on catalyst activity and improve the applicability of the technology. Related Articles | Metrics

Select

Recent progress of heterogeneous catalysts towards selective catalytic reduction of NO by CO under oxygen-rich conditions Yaqi LIU Yan LIU Ke WU Liwen XING Dianxing LIAN Mohaoyang CHEN Jianjun JI Yongjun JI The Chinese Journal of Process Engineering    2024, 24 (3): 284-296.   DOI: 10.12034/j.issn.1009-606X.223136 Abstract （651）   HTML （15）    PDF （3784KB）（413）       Knowledge map    Save Nitrogen oxides (NOx), as one of the predominant atmospheric pollutants mainly derived from automobile exhaust and industrial waste gas, have played the role of an inevitable precursor that led to acid rain, photochemical smog, and other environmental contamination issues. In addition to atmospheric pollution, the growing emissions of NOx pollutants also give rise to a serious threat to agricultural production and human health. Thus, it is of urgent need to develop feasible NOx abatement strategies. Selective catalytic reduction of NO by CO (CO-SCR) is a very promising denitrification technology that can simultaneously remove harmful gases of NO and CO, making it one of the most ideal solutions for flue gas treatment. To promote its industrial applications, CO-SCR should have a low operating temperature ranging from 150℃ to 250℃ and superior resistance to oxygen poison. Therefore, there is an urgent need to develop efficient CO-SCR catalysts used under oxygen-rich conditions for abating severe environmental pollution problems. This work provides a comprehensive review of the research progress and latest research findings of CO-SCR under oxygen-containing conditions. The research advances of Pd, Ir, Rh, Mn, and Co-based heterogeneous catalysts were introduced, and the effects of active components, promoters, and supports on the catalytic performance of CO-SCR are described in detail. In this section, the preparation method, doping modification, and reaction conditions are analyzed. Meanwhile, the impact of O2, H2O, and SO2 on the catalytic activity of CO-SCR is discussed, in which the inhibition mechanism of O2 is summarized. Finally, the challenges and future developments of CO-SCR under oxygen-rich conditions are summarized and the corresponding coping solutions are proposed. We hope this review can provide an in-depth understanding and useful guidance for the rational design of efficient heterogeneous catalysts for the CO-SCR reaction in practical applications. Related Articles | Metrics

Select

Surface modification and catalytic performance study of Cu-based carbon dioxide to methanol hydrogenation catalyst Qiang YANG Gang WANG Chunshan LI The Chinese Journal of Process Engineering    2024, 24 (10): 1166-1176.   DOI: 10.12034/j.issn.1009-606X.224059 Abstract （1303）   HTML （28）    PDF （3618KB）（392）       Knowledge map    Save Development of effective copper-based catalyst for CO2 hydrogenation to methanol is of great significance, considering the utilization of this greenhouse gas. In this work, a series of surface promoter-modified (Mn, In, Mo, Mg, Zr) catalyst were synthesized by coprecipitation-post impregnation method and evaluated for CO2 hydrogenation to methanol in fixed-bed reactor. The role of metal modifier on the physicochemical properties of Cu/ZnO/Al2O3 (CZA) were investigated through CO2-TPD, XRD, XPS and H2-TPR. In addition, the catalytic mechanism for CO2-to-methanol hydrogenation was revealed by employing in situ IR. The results showed that the Mn-modified CZA with good reduction behavior, excellent CO2 adsorption capacity and suitable Cu+/Cu0 ratio exhibited the best performance. The metal element loaded on catalyst strengthened the interactions between the copper and support, suppressing the growth of Cu. The appropriate Cu+/Cu0 ratio facilitates the stabilization and conversion of methoxy, resulting in increased methanol production. Compared to the untreated CZA catalyst, the Mn-modified catalyst has more medium strong base sites on the surface, which helps to adsorb more CO2 for further hydrogenation to form formate, methoxyl and other intermediates. The incorporation of metal component in CZA facilitated the catalyst reduction ability. The catalytic mechanism follows the formate pathway and the methoxyl species is the crucial intermediate. The Cu nanoparticles on the catalyst surface showed an increased capacity for H2 dissociation when using Mn-modified CZA catalysts. This is due to stronger metal-carrier interactions. The presence of interstitial H in the carriers contributed to the generation of formate species. The dissociated H atoms from the surface Cu nanoparticles replenished the consumed interstitial H. The modified catalyst's interstitial H presence and enhanced H2 dissociation ability accelerated the formation and conversion of intermediate species, promoting methanol generation. Related Articles | Metrics

Select

Research progress on preparation of magnetic activated carbon and its application in water treatment Qianyu WANG Yuming ZHANG Yanbin CUI The Chinese Journal of Process Engineering    2024, 24 (3): 259-272.   DOI: 10.12034/j.issn.1009-606X.223228 Abstract （698）   HTML （23）    PDF （2257KB）（388）       Knowledge map    Save Activated carbon (AC) has the characteristics of high specific surface area, porosity, abundant surface functional groups and chemical stability, and these advantages make it a widely used adsorbent in water treatment. After being exhausted (saturated adsorption contaminants), the spent AC needs to be separated from aquatic systems and regenerated which is conductive to materials recycling. However, it is difficult to efficiently separate the powder AC saturated adsorption contaminants from aquatic systems by traditional separation methods (gravitational sedimentation, centrifugation, filtration, and flotation), and the disadvantages for these methods root in many aspects including time-consuming, high-cost, and low separation efficiency. These limit the wide application of activated carbon in the field of water treatment to some extent. Magnetic modification treatment on AC can provide a magnetic activated carbon (MAC) which possesses better performances reflecting in higher adsorption capacity, and can be easier, rapid and efficient separation through external magnetic fields. At the same time, MAC has good catalytic activity, which is useful for enhancing the capability of advanced oxidation process to efficiently degrade organic pollutants in aquatic systems. Therefore, MAC has broad application prospects in the field of water treatment. This work mainly introduces the preparation methods (co-precipitation method, thermochemical method, and mechanical milling method), microstructure and physicochemical properties (specific surface area, pore structure, magnetism, crystal and chemical structure, surface charge) of MAC. The research progress of MAC in wastewater treatment in recent years is reviewed, consisting of organic pollutant removal, heavy metal removal and other applications. The adsorption characteristics (adsorption isotherms and adsorption dynamics) and corresponding influencing factors (adsorption temperature, solution pH, and coexisting ions) are summarized in details. And the regeneration methods of AC are investigated comprehensively. In the end, the development and prospect of the application of MAC in water treatment are also discussed. Related Articles | Metrics