微通道中硝基胍的连续流合成工艺研究

Research on Continuous Synthesis of Nitroguanidine in the Micro-channel Reactor

摘要:

以硫酸胍和硝硫混酸为原料，在微通道中进行管式流动硝化反应，形成了硝基胍的连续流合成工艺。研究了混酸浓度、反应温度、停留时间、物料摩尔比等工艺参数对合成反应的影响。获得的优化工艺参数为：90%HNO3:98%H2SO4=2:1(v/v)，反应物与硝酸摩尔配比为1:1.2，反应温度为60 ℃，停留时间为30 s，此时硫酸胍的转化率为87.9%，硝基胍收率为86.1 %。与传统间歇釜式合成工艺相比，连续流工艺实现了硝基胍合成反应的稳定进行，消除了过程反应热的积累和温度波动，解决了硝基胍的合成安全性问题，缩短了反应时间，提高了产率，减少了废酸排放量。

Abstract:

This work indicates that the nitration of guanidine salt can be carried out in continuous mode using the microreactor system. With sulfuric acid guanidine as raw material and sulfuric acid and sulfuric acid mixture as nitrating agent，the influences of the mixed acid concentration, reaction temperature, residence time, ratio of two materials on the yield of nitroguanidine were carried out. The optimal reaction conditions are shown as follows: 90% HNO3: 98% H2SO4 = 2: 1 (v / v), 1:1. 2 of molar ratio of sulfuric acid guanidine and nitrating agent. The conversion of the sulfuric acid guanidine can reach 87.9% and the yield of the nitroguanidine can reach 86.1%. Compared with the traditional process, new technology based on micro-channel continuous flow greatly improves production efficiency and reduces costs.