置换脱盐法合成甘氨酸的实验研究

Experimental Study of Glycine Synthesis by the Method of Ion Exchange

以高纯度固体氯乙酸(含量≥99%)为原料、乙醇为溶剂、乌洛托品为催化剂、碘化铵为助催化剂,通氨反应合成甘氨酸,收率最高可达95%以上,甘氨酸主含量为98.5%左右,氯根含量为0.4%左右。最佳实验条件:氯化铵合成工序,反应温度50℃,反应时间2 h,固体氯乙酸与碘化铵物质的量比为1∶1.6,乙醇加入量1200 mL;甘氨酸合成工序,反应温度为50℃、保温时间为4 h、乌洛托品加入量为氯乙酸质量的40%,乙醇加入量200 mL。

Industrial Glycine was produced with new method in which chloroacetic acid and ammonia gas was main reactant,athanol was solvent,paraformaldehyde was main catalyst,ammonium iodide was cocatalyst.The yield of product was up to 95%,the content of glycine was up to 98.5%,and the content of chloride ion was below 0.4%.In the process of ion exchange,the optimal parameter was that keeping the volume of athanol at 1200 mL,the proportion of the chloroacetic acid and ammonium iodide at 1∶1.6,the reactive temperature at 50℃,the reactive duration at 2 hours.Meanwhile,the key factors influencing on the yield of glycine were the reactive duration,temperature and the dosage of paraformaldehyde.The optimal reactive duration was 4 hours,reactive temperature was 50℃,and the dosage of paraformaldehyde was equal to 40%of chloroacetic acid.