| 摘要 |
<PICT:0569716/IV/1> p The production of halohydrins by the reaction of hypohalogen acids with unsaturated compounds such as allyl chloride or olefines is effected with the pH maintained at 4.5-8. This inhibits the formation of halogenides. In an example, an unsaturated halide such as allyl chloride and water are introduced at 10 and 11 respectively into a pipe 12, wherein they are mixed with reaction products from the reaction chamber 13 and the mixture is delivered by pump 14 and pipe 15 to the chamber 13 which receives dilute hypochlorous acid and some glycerol dichlorhydrin supplied to the reaction vessel by a pipe 16, the pH being maintained within the stated range. The reaction product is withdrawn by a pipe 17 to a neutralizer 18. If the contact period in the chamber 13 is insufficient, an additional storage or reaction chamber may be provided in the pipe 17. Sodium hydroxide or the like is supplied to the neutralizer chamber 18 to raise the pH to 10-11. The neutralized mixture is led to a separator 22 in which the small quantity of insoluble product (halides) is allowed to settle and is removed at 23, while the aqueous layer containing the dichlorhydrin is removed at 24, a part being byepassed to a pipe 25 and pump 28. Chlorine is fed in at 26 and sodium hydroxide or the like may be fed in at 27 to maintain the desired pH in the reaction chamber. Specifications 126,311, 128,578 and 128,635, [all in Class 2 (iii)], are referred to. |
