Recycling Acetonitrilefrom Waste Water Of LLM-105 By Salting-out Extraction

Separation of azeotropic mixture by salt effect has important background in industry. Compared to traditional azeotropic distillation or extractive distillation process,the method can greatly reduce the energy consumption and is also consistent with the development of low-carbon.LLM-105 a new type of high energy low sense of explosives, mainly produced by oxidation, nitration, amination and nitrogen oxide synthesis of four steps.The amination reaction process produces a large number of acetonitrile solution, for the treatment and recycling of the waste liquid acetonitrile has yet to see the reports. As a result, recycling acetonitrile by salt effect has important significance to reduce the cost and environmental pollution.In this paper,salt selection and salt extraction of acetonitrile-water mixtures were studied by theoretical analysis and experiment. And we determined that calcium chloride is the best choiceBased on the research above, we worked on LLM-105 amination reaction waste water by the combination of distillation of salt extraction.Optimum conditions of salt extraction were investigatedw(CaCl2)=60%,temperature 20-30℃,and the extracting ratio m(CaCl2 aqueous solution)/m(acetonitrile-water mixture)=0.5:1. Under such conditions, the concentration of acetonitrile in extract phase could reach 95.86%,in addition, the stability of CaCl2 aqueous solution was investigated. Then the distillation residual liquid was dealt with by active carbon adsorption, and the COD removal rate reached to 98.8%.Finally we achieved disposal of LLM-105 amination waste water and the acetonitrile recovery by salt extraction according to the requirements.