Continuous preparation of dimethylvinylcarbinol by isomerizing prenol
    1.
    发明授权
    Continuous preparation of dimethylvinylcarbinol by isomerizing prenol 失效
    通过异构化prenol连续制备二甲基乙烯基甲醇

    公开(公告)号:US06180839B2

    公开(公告)日:2001-01-30

    申请号:US09265923

    申请日:1999-03-10

    IPC分类号: C07C2700

    CPC分类号: C07C29/56 C07C33/03

    摘要: A process is described for the continuous preparation of dimethylvinylcarbinol (DMVC) by continuously reacting prenol with the aqueous solution of a protic acid in the still or in the lower part of a rectification column while distilling off the DMVC formed in the form of an azeotropic mixture with water, which comprises a) during the reaction ensuring that as far as possible no liquid two-phase mixture forms in the reaction mixture, b) distilling off the DMVC which forms at a reflux ratio of at least 2, as a result of which there is virtually no more prenol present in the distillate from the column, and c) setting the reaction volume and/or the amount of prenol added per hour and/or the concentration of protons in the reaction mixture in such a manner that the quotient, defined as residence time concentration coefficient, of the reaction volume and the volume of prenol added per hour multiplied by the concentration of protons in the reaction mixture has a value between 0.001 h·mol/l and 1 h·mol/l. In this connection, the formation of a liquid two-phase mixture in the reaction mixture is prevented, in addition to avoiding too large a prenol excess, by continuously taking from the reaction mixture a partial stream, passing it over a phase separation vessel, completely or at least largely removing there the small quantities, formed in the course of the reaction, of organic by-products which are insoluble or only partially soluble in water, and returning the aqueous phase to the reaction volume.

    摘要翻译: 描述了通过在精馏塔的静止或下部连续地反应预先醇与质子酸的水溶液连续反应制备二甲基乙烯基甲醇(DMVC)的方法,同时蒸馏出以共沸混合物形式形成的DMVC 在反应过程中包含a)的水,确保尽可能在反应混合物中形成液体两相混合物,b)蒸发形成回流比至少为2的DMVC,结果是在那里 在柱的馏出物中基本上没有更多的prenol存在,并且c)使反应体积和/或每小时加入的prenol的量和/或反应混合物中的质子浓度设定为使得定义为 停留时间浓度系数,反应体积和每小时加入的prenol体积乘以反应混合物中质子浓度的值为0.001 h.mol / l和 1 h.mol / l。在这方面,防止反应混合物中的液体两相混合物的形成,除了避免过多的过量的过量以外,通过连续取出反应混合物的一部分流,将其通过 在相分离容器中,完全或至少大部分在反应过程中形成的少量去除不溶或仅部分溶于水的有机副产物,并将水相返回到反应体积中。