申请人:SHELL INTERNATIONALE RESEARCH
MAATSCHAPPIJ B.V.
公开号:EP0256576A1
公开(公告)日:1988-02-24
A continuous process for the production of dichlorohydrin which comprises in sequence
(a) reacting allyl chloride, water and chlorine in a first reaction zone to form an aqueous reaction mixture of dichlorohydrin and reaction by-products,
(b) passing the reaction mixture as feed to an electrodialysis zone, said electrodialysis zone having a feed inlet and a diluate (product) outlet, a concentrate inlet and a concentrate outlet,
(c) electrodialyzing said feed in said electrodialysis zone to remove ions formed during the reaction from said feed into a concentrate stream and to obtain a diluate stream containing dichlorohydrin and having a lower ion content than said feed,
(d) adding a basic substance to said diluate stream to neutralize at least a majority of the hydrogen ions present in said diluate while maintaining the pH of said diluate below 6.9,
(e) subjecting said diluate to reverse osmosis in a reverse osmosis zone to obtain: (1) a retentate stream having a higher dichlorohydrin concentration than said diluate, and (2) a permeate stream of relatively pure water,
(f) recycling a major portion of said permeate stream to the reaction zone,
(g) passing at least a portion of at least one of: (1) said permeate stream and/or (2) said retentate stream, to the concentrate inlet of said electrodialysis zone,
(h) withdrawing an ion concentrate stream from said electrodialysis zone, and
(i) withdrawing any retentate stream which was not passed to said electrodialysis zone.
一种生产二氯海德林的连续工艺,包括以下步骤
(a) 在第一反应区使烯丙基氯、水和氯反应,形成二氯海德林和反应副产物的水反应混合物、
(b) 将反应混合物作为进料送入电渗析区,所述电渗析区有一个进料口和一个稀释液(产品)出口,一个浓缩物进料口和一个浓缩物出口、
(c) 在所述电渗析区对所述进料进行电渗析,以去除反应过程中形成的离子,使其从所述进料进入浓缩物流,并获得含有二氯海德林且离子含量低于所述进料的稀释液流、
(d) 向所述稀释液中加入碱性物质,以中和至少大部分存在于所述稀释液中的氢离子,同时将所述稀释液的 pH 值保持在 6.9 以下、
(e) 在反渗透区对所述稀释液进行反渗透,以获得:(1) 比所述稀释液具有更高二氯海因浓度的回流液,以及 (2) 相对纯净的渗透水流、
(f) 将所述渗透流的大部分回收至反应区、
(g) 将 (1) 所述渗透液流和/或 (2) 所述回流液流中的至少一部分流向所述电渗析区的浓缩物入口、
(h) 从所述电渗析区提取离子浓缩物流,以及
(i) 抽出未进入所述电渗析区的任何回流液。