申请人:——
公开号:US20020042543A1
公开(公告)日:2002-04-11
Process for the production of unsaturated ethers, in particular isopropenyl methyl ether (IPM), by pyrolysis of a ketal-containing or acetal-containing mixture, in particular dimethoxypropane (DMP), in the liquid phase in the presence of an organic carboxylic acid, according to the following reaction scheme:
1
wherein R
1
=H or alkyl with 1-8 C atoms; R
2
=H, CH
3
—, C
2
H
5
—, or Cl—; R
3
=alkyl with 1-8 C atoms; R
4
=H, CH
3
—, C
2
H
5
—, or C
3
H
7
—, and R
1
and R
4
may be joined to form a 5-, 6-, or 7-membered ring. DMP is produced by the process from acetone and methanol by reaction in an acidic heterogeneous ion exchanger, the product being isolated by extraction with aqueous alkaline solution. In particular the process involves combining the IPM reaction product with the DMP reaction product, which permits the execution of a stable recycling process in which the methanol-containing streams of the IPM and DMP stages can be simultaneously extracted. The product may be isolated by the process by simple distillation of IPM from a mixture containing IPM, DMP and acetone.
生产不饱和醚,特别是异丙烯基甲基醚(IPM)的方法,通过热解含有缩酮或醛缩合物的混合物,特别是二甲氧基丙烷(DMP),在液相中在有机羧酸的存在下,根据以下反应方案:1其中R1等于H或具有1-8个碳原子的烷基;R2等于H,CH3—,C2H5—,或Cl—;R3等于具有1-8个碳原子的烷基;R4等于H,CH3—,C2H5—,或C3H7—,并且R1和R4可以连接形成5、6或7元环。DMP是通过将丙酮和甲醇在酸性非均相离子交换剂中反应的过程生产的,产物通过用碱性水溶液萃取来分离。特别是该过程涉及将IPM反应产物与DMP反应产物结合,这允许执行稳定的循环过程,其中IPM和DMP阶段的含甲醇流可以同时被萃取。产物可以通过简单地从含有IPM、DMP和丙酮的混合物中蒸馏IPM的过程来分离。