At present, in view of the existing problems in waste phosphor, such as lower comprehensive utilization and serious environmental pollution caused by improper handling, the method of sulfation-roasting?leaching was used to pre-treatment waste phosphor according to its problems to explore the effect of roasting temperature on the form of materials, roasting temperature and concentrated sulfuric acid addition on rare earth leaching. A preliminary environmental assessment of the process was carried out. The results showed that with the optimum leaching conditions which were roasting temperature of 300℃, roasting time of 120 min, concentrated sulfuric acid?waste phosphor mass ratio of 1.85, leaching temperature of 25℃, leaching time of 120 min and liquid?solid mass ratio of 2:1, the sulfation-roasting?leaching rate of rare earth oxides were Y2O3 98.82%, Eu2O3 97.39%, CeO2 96.58% and Tb4O7 98.77%. The material after sulfation-roasting?leaching indicated that sulfation-roasting can decompose rare earth into soluble sulfate and phosphate, and ensure that the slag was environmentally friendly and low slag. Concentrated sulfuric acid addition gave greater impact on the leaching of four kinds of rare earth, while roasting temperature brought larger influence on the leaching of CeO2 and Tb4O7, leaching rates increased from 40.18% and 37.18% at 200℃ to 96.58% and 98.77% 300℃, respectively. Waste phosphor calcined at 300℃ will not produce harmful gases such as SO2 and SO3 through the discussion of the emission of gas during the roasting process, the main gases released during roasting were water vapor and volatile sulfuric acid, and the material loss was about 10%. This process avoided the production of a large amount of sulfur-containing, fluorine-containing, strongly acidic waste gas and refractory roasting waste residue in the roasting process, and reduced environmental pollution and waste of rare earth resource, the new process has good prospects for industrial applying.
[1]李霞, 赵栋梁, 张羊换, 等. 添加剂CeO2对La2Mg(17)-50% Ni储氢性能的影响[J]. 稀土, 2015, 36(2):15-20.
Li X, Zhao D L, Zhang Y H, et, al. Catalytic effect of CeO2 on hydriding/ dehydriding properties of La2Mg (17)50% Ni alloy[J]. Chinese Rare Earths, 2015, 36(2):15-20.
[2]朱凯, 侯仰龙. 稀土永磁纳米材料的控制合成及其磁学性能[J]. 稀有金属, 2017, 41(5):466-474.
Zhu K, Hou Y L. Controllable Synthesis of Rare-Earth Based Permanent Magnetic Nanomaterials and Their Magnetic Properties[J]. Chinese Journal of Rare Metals, 2017, 41(5):466-474.
[3]吴玉锋, 顾一帆, 李艳梅. 我国废弃荧光灯回收再利用标准体系框架研究[J]. 中国标准化, 2013(11):67-71.
Wu Y F, Gu Y F, Li Y M. Study on recycling standard system of spent fluorescent lamps in china[J]. China Standardization, 2013(11):67-71.
[4]李雨, 徐欣欣, 雷鹰, 等. 机械活化浸出废荧光粉中稀土氧化物实验研究[J]. 稀土, 2016, 37(5):72-78
Li Yu, Xu X X, Lei Y, et, al. Research on the mechanical activation leaching of REOs from waste fluorescent powder[J]. Chinese Rare Earths, 2016, 37(5):72-78.
[5]赵卓, 徐桂丽. 废弃荧光粉中稀土元素的回收技术现状与发展趋势[J]. 中国稀土学报, 2015, 33(6):641-649.
Zhao Z, Xu G L. Present Situation and development trend of technology of rare earth elements in waste phosphor[J]. Journal of The Chinese Socity of Rare Earths, 2015, 33(6):641-649.
[6]李宏煦, 王帅, 李超. 稀土元素回收技术及其生命周期循环分析[J]. 稀有金属, 2016, 40(9):945-954
Li H X, Wang S, Li C. Recycling and life cycle analysis of rare earth elements[J]. Chinese Journal of Rare Metals, 2016, 40(9):945-954.
[7]Hirajima T, Bissombolo A, Sasaki K, et al. Floatability of rare earth phosphors from waste fluorescent lamps[J]. International Journal of Mineral Processing, 2005, 77(4):187-198.
[8]Mei G, Rao P, Matsuda M, et al. Separation of red (YO:Eu), blue (BaMgAlO:Eu) and green (CeMgAlO:Tb) rare earth phosphors by liquid/liquid extraction[J]. Journal of Wuhan University of Technology--Materials Science Edition, 2009, 24(4):603-607.
[9]Otsuki A, Mei G, Jiang Y, et al. Solid-Solid Separation of Fluorescent Powders by Liquid-Liquid Extraction Using Aqueous and Organic Phases[J]. Resources Processing, 2006, 53(3):121-133.
[10]Hirajima T, Sasaki K, Bissombolo A, et al. Feasibility of an efficient recovery of rare earth-activated phosphors from waste fluorescent lamps through dense-medium centrifugation[J]. Separation & Purification Technology, 2005, 44(3):197-204.
[11]申星梅, 李辽沙, 武杏荣, 等. 废弃CRT荧光粉中稀土的提取工艺与技术[J]. 化工学报, 2015, 66(4):1498-1505.
Shen X M, Li L S, Wu X R, et, al. Recovery of rare earth from waste CRT phosphor[J]. CIESC Journal , 2015, 66(4):1498-1505.
[12]李洪枚. 从废稀土荧光粉中酸浸回收稀土的研究[J]. 稀有金属, 2010, 34(6):110-116.
Li H M. Recovery of rare earths from phosphor sludge by acid leaching[J]. Chinese Journal of Rare Metals, 2010, 34(6):110-116.
[13]吴玉锋, 贾平平, 王维, 等. 从废弃CRT荧光粉中熔浸稀土元素的研究[J]. 中国稀土学报, 2013, 31(6):723-727．
Wu Y F, Jia P P, Wang W, et, al. Leaching of rare earth elements from waste fluorescent powder of cathode ray tube by molten salts[J]. Journal of The Chinese Socity of Rare Earths, 2013, 31(6):723-727．
[14]张兆雪, 王瑞祥, 熊家春,等. 碱熔预处理对废旧稀土荧光粉中稀土提取的影响[J]. 有色金属科学与工程, 2016, 7(6):129-135.
Zhang Z X, Wang R X, Xiong J C, et, al. Effect of alkaline fusion pretreatment on extraction rate of rare earth from waste rare earth fluorescent powder[J]. Nonferrous Metals Science and Engineering, 2016, 7(6):129-135.
[15]王秀艳, 李梅, 许延辉, 等. 包头稀土精矿浓硫酸焙烧反应机理研究[J]. 湿法冶金, 2006, 25(3):134-137.
Wang X Y, Li M, Xu Y H, et, al. Study on decomposition mechanism of rare earth concentrate by concentrated sulfuric Acid[J]. Hydrometallurgy of China, 2006, 25(3):134-137.
