咖啡因合成的绿色技术

以 3R原则 (Reduce,Reuse,Recycle)评论了合成咖啡因工业绿色技术的进展。缩合反应的副产物醋酸可再利用生产氯乙酸和盐酸 ,完成闭合循环。以振动筛板塔萃取咖啡因不仅提高了收率 ,而且降低了高毒溶剂氯仿的用量和能耗。萃残液中溶解和夹带的氯仿 ,可用磺化煤油萃取和蒸馏回收。茶碱结晶后的母液 ,可用 2 -乙基己醇萃取回收其中的茶碱。 1,3-二甲基 - 5亚硝基脲嘧啶的电催化加氢是取代还原剂铁粉或氢气有应用前景的绿色技术

Green technology for caffeine synthesis

This paper reviews the development of green technologies for the caffeine synthesis industry following the 3R (Reduce, Reuse, Recycle) rule. The by-product acetic acid from condensation can be recovered and recycled for production of chloroacetic acid and hydrochloric acid. A reciprocating plate extraction column is used to recover the caffeine not only to increase the yield but also to reduce the amount of the chloroform feed and the energy consumption. The highly toxic chloroform in the aqueous effluent can be recovered with an extraction-distillation process using sulfonated kerosene. A 2-ethylhexanol extraction process was developed to recover the theophylline in the aqueous effluent. The electrocatalysis hydrogenation of 1,3-dimethyl-4-amino-5-nitrouracil is a potential green technology for replacing the reductant, such as iron powder or hydrogen gas.