N-乙烯基己内酰胺的合成

乙炔为乙烯化剂,分别在500 mL搅拌釜式反应器、500 mL塔式反应器和8 000 mL喷射环流反应器中,研究了N-乙烯基己内酰胺(NVCL)的合成。用己内酰胺(CL)和KOH制得己内酰胺钾盐为催化剂,添加助催化剂18-冠醚-6,以乙炔和己内酰胺为原料,常压法合成NVCL。粗产品经减压蒸馏及进一步精馏分离得到质量分数98%的NVCL。用FTIR、GC/MS对它的结构进行了测试和表征。研究结果表明,釜式反应器中CL转化率为30.5%时,NVCL选择性为73.4%;塔式反应器中CL转化率为31.4%时,NVCL选择性为79.2%;喷射环流反应器中CL转化率为56.7%时,选择性达85.6%。抑制反应过程中物料的黏稠化是制约合成放大成功的关键因素。

Synthesis of N-Vinylcaprolactam

The synthesis of N-vinylcaprolactam(NVCL),with acetylene as vinylation agent,was studied in a 500 mL stirred reactor system,a 500 mL tower reactor system and a 8 000 mL jet loop reactor system,respectively.With potassium caprolactam as catalyst and adding 18-crown-6 as co-catalyst,NVCL was synthesized by the reaction of acetylene with caprolactam(CL) under normal pressure.The resulting crude products were purified by vacuum distillation and further distillation separation process to get NVCL of high purity(98%).Structure of the product was characterized by means of FTIR and GC/MS.The CL conversion and the product selectivity in the stirred tank reactor are 30.4% and 73.4%,in the tower reactor 31.4% and 79.2%,and in the jet loop reactor 56.7% and 85.6%,respectively.Resinification of the reaction mixture is a key factor of controlling successful synthesis.