Green process for producing nitroguanidine

Abstract

The invention relates to a green process for producing nitro guanidine, and belongs to the field of chemical engineering. The discontinuous nitrification method is adopted in the invention to prepare the nitro guanidine. The method particularly comprises that: guanidine nitrate is added in concentrated nitric acid while stirring, diluted by water and subjected to decompression and sucking filtration to separate out a crystal, so that the coarse product of the nitro guanidine is obtained; and the coarse product of the nitro guanidine is water-washed for more than four times to obtain the target product. The process is simple and saves the process of the decompression, distillation and recovery of the nitric acid, and the diluent uses water to replace the nitric acid, and the lowest reaction temperature is reduced from 60 DEG C to 30 DEG C, thereby lowering the decomposition of the nitro guanidine in the concentrated nitric acid, and the fastest reaction time is shortened from 3 hours to 20 minutes, and the production efficiency is greatly improved; due to the adoption of the discontinuous method, the prior idle production equipment can be used for production by simple modification; moreover, in the process, the content of the waste nitric acid is more than 45 percent, so that the nitro guanidine can be used as an oxidant and a neutralizer to produce various products such as sodium nitrate, oxalic acid, p-nitrodracylic acid and the like.

Description

technical field [0001] The invention relates to a green process for producing nitroguanidine, which belongs to the technical field of chemical synthesis. Background technique [0002] Nitroguanidine is a white crystal with a melting point of 232°C, an explosion point of 275°C / 5s, and a power of 104% (TNT equivalent). It is an important industrial raw material. A variety of alkyl and aryl derivatives can be prepared by using nitroguanidine as a raw material through different routes. It is usually used as a propellant and explosive charge component, as a gas-generating component It is widely used in the air bag system of motor vehicle or aircraft. [0003] The traditional method of producing nitroguanidine is the sulfuric acid dehydration method, adding concentrated sulfuric acid into the reactor, cooling to 5°C, and slowly adding metered guanidine nitrate at a temperature of 5-20°C. After adding guanidine nitrate, react at 10-20°C for half an hour. Then add the reactants i...

AI Technical Summary

Problems solved by technology

[0007] The purpose of the present invention is to provide a green process for producing nitroguanidine, which adopts the intermittent nitration method to prepare nitroguanidine, and solves the problems that a large amount of waste acid will be produced in the traditional method of preparing nitroguanidine, and the yield is low.