Abstract: Imidazolium-based ionic liquids (ILs) have garnered significant attention as foundational materials in sustainable chemical engineering, owing to their negligible volatility, exceptional thermal stability, and highly tunable structural properties. These characteristics make them particularly valuable for applications such as green solvents, advanced catalysis, and energy storage. This research detailed a comprehensive investigation into the development, optimization, and analysis of an industrial-scale green synthesis pathway for 1-butyl-3-methylimidazolium chloride ([Bmim]Cl), which was prepared through a quaternization reaction using N-methylimidazole and 1-chlorobutane as raw materials.Subsequently, reaction parameters were optimized and the implementation of process intensification strategies to enhance production efficiency and environmental sustainability. Experimental results combined with economic analysis identified the optimal synthesis conditions as a reaction temperature of 76℃, N-methylimidazole to 1-chlorobutane molar ratio of 1∶1.3, and a reaction time of 36 h. Under these optimized parameters, a consistently high single-pass yield of 95.6% was achieved. Kinetic studies revealed that there was a significant correlation between reaction temperature, reactant molar ratio, and conversion efficiency. The calculated activation energy (Ea≈135.7 kJ/mol) indicated a pronounced temperature dependence of the reaction rate. Building upon reaction optimization, a pivotal aspect of this work involved the design and implementation of an advanced closed loop material recycling system. This integrated internal recycling mechanism enabled the near-complete recovery and reuse of unreacted feedstocks and solvents, achieving high recovery rates of 99.5% for 1-chlorobutane and 98.1% for ethyl acetate. By significantly curtailing raw material consumption and waste generation, this approach aligned intrinsically with green chemistry principles and propelled the process toward near zero emissions. In conclusion, this pathway not only offers a scalable model for the manufacture of [Bmim]Cl, but also provides a transferable strategy for the synthesis of other value-added ionic liquids, thereby representing a substantial advancement in the field of sustainable process engineering.

Key words: 1-butyl-3-methylimidazole chloride, N-methylimidazole, 1-chlorobutane, dynamics, scale-up, green synthesis

摘要： 咪唑类离子液体因其低挥发性、高热稳定性及可设计性强等特点，已成为绿色化学与过程强化领域的关键材料。本研究针对1-丁基-3-甲基咪唑氯盐([Bmim]Cl)的规模化绿色制备工艺展开系统研究。以N-甲基咪唑和1-氯丁烷为原料，通过反应条件优化与过程强化设计，显著提升产物收率与过程可持续性。实验结果表明，在反应温度76℃、配料比(N-甲基咪唑∶1-氯丁烷)1∶1.3、反应时间36 h条件下，产物单程收率达95.6%。反应动力学研究表明，反应体系的温度、配比与转化率之间存在显著相关性；活化能计算结果(Ea≈135.7 kJ/mol)进一步揭示了规模化制备反应速率对温度变化的敏感性。同时，本研究建立了完善的物料循环利用体系，对原辅材料充分回收利用，1-氯丁烷和乙酸乙酯回收率分别达99.5%和98.1%，制备过程近零排放。通过绿色化工程措施和经济技术分析论证，实现了规模制备过程的绿色化和高效化。该绿色合成路线为离子液体的大规模工业制备提供了可行范式，具有良好的工业放大潜力和经济效益。

关键词: 1-丁基-3-甲基咪唑氯盐, N-甲基咪唑, 1-氯丁烷, 动力学, 规模化, 绿色合成