In the chemical industry organic solvents should be avoided wherever possible. They are often toxic to marine organisms and plants as well as to higher organisms and humans. Moreover, volatile organic compounds (VOC) cause air pollution which leads to the necessity of expensive separation technologies like waste water or exhaust gas treatments. Solutions for these problems are either the development of processes without the use of any solvent or the use of environmentally benign solvents such as water. In this contribution it is shown how versatile water can be, used as a solvent in homogeneously catalysed processes, for example, telomerisation reactions with methanol, diethylamine, ethylene glycol and glycerol. In this context another positive effect of the solvent water is the ecologically and economically required retention of the transition metal catalyst inside the process. Furthermore, different reactor types, a loop reactor and a mixer-settler reactor, are presented to cope with the challenges of mass transport limitations and selectivity control in aqueous biphasic systems.
在
化学工业中,应尽可能避免使用有机溶剂。它们通常对海洋
生物和植物以及高等
生物和人类有毒。此外,挥发性有机化合物(VOC)会造成空气污染,因此必须采用昂贵的分离技术,如废
水或废气处理。解决这些问题的办法要么是开发不使用任何溶剂的工艺,要么是使用对环境无害的溶剂,如
水。本论文展示了
水在均相催化过程中作为溶剂的多功能性,例如与
甲醇、
二乙胺、
乙二醇和
甘油的端聚反应。在这种情况下,溶剂
水的另一个积极作用是在工艺中保留过渡
金属催化剂,这既符合生态学要求,也符合经济学要求。此外,还介绍了不同类型的反应器(循环反应器和混合器-沉降器反应器),以应对
水基双相系统中质量传输限制和选择性控制的挑战。