研究了以氯乙酸和硫氢化钠为原料,在常压串联组合反应器中连续合成巯基乙酸工艺.考察了原料物质的量比、反应物浓度、反应时间及反应温度等因素对巯荃乙酸收率的影响.结果表明,在氯乙酸与硫氢化钠物质的量比为1:2.5,溶液氯乙酸质量分率20%,硫氢化钠质量分率15%的条件下.反应物料先在连续操作搅拌釜式反应器中于10℃反应10 min,然后在管式反应器中于55℃继续反应9 min,巯基乙酸的收率可以达到90%以上.该工艺在实现过程连续化的同时,提高了产品收率.%Thioglycolic acid (TGA) was continuous synthesized from chloroacetic acid (CAA) and sodium hydrosulfide (SHS) under common pressure in the combination reactors. Effects of the process conditions on the yield of TGA were investigated, such as molar ratio of CAA to SHS, mass fraction of material, reaction time and temperature in the tank and tubular reactors respectively. The yield of TGA beyond 90％ was obtained under such optimal conditions as molar ratio of chloroacetic acid to sodium hydrosulfide was 1:2.5, the concentration of chloroacetic acid and sodium hydrosulfide were 20％ and 15％ mass fraction respectively, the residence time of continuous tank reactor was 10 min, reaction temperature 10℃, the residence time of tubular reactor was 9 min,reaction temperature 55℃. The higher yield of TGA was obtained in continuous operation by this optimal proeess.
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