Study On Purification Of Chlorantraniliprole By Dissolution Crystallization

Chlorantraniliprole,an adjacent formyl amide benzamide,with its low toxicity and high efficiency,has long been an important substanced used for pesticide,relevant research mainly focus on its synthesis methods but not its purification and refinement rougher.Therefore,this paper illustrated the research on various methods to purify chlorantraniliprole crystals.So as to provide data for its production.When studying the thermodynamic properties of chlorantraniliprole,the Dmol3 module of Materials Studio was used to simulate the interations between chlorantraniliprole & various solvents and their binding energy.By comparing experimental results and the models,it was found that dimethylformamide as an optimum solvent.Laser method was used to measure the solubility of chlorantraniliprole in methanol solution and dimethylformamide-methonal-water system under different temperatures.The results obtained from different solvent systems were fitted with a polynomial empirical equation and modified Apelblat equation.Finally,thermodynamic properties of chlorantraniliprole in dimethylformamide-methonal-water system such as Solution,Entropy and Gibbs were predicted and analysed.In the study of the crystallization kinetics of chlorantraniliprole,the induction period of chlorantraniliprole in dimethylformamide-methonal-water system was determined by laser method.By fitting the data of induction periods under different temperations,it was concluded that the chlorantraniliprole followed the nucleation mode under dimethylformamidemethonal-water system.Baesd on this conclusion,its crystal nucleation and growth mechanism was analysed with calculation on its crystal-solution surface tension and surface entropy faction under different temperatures.Besed on the results of crystallization the thermodynamic and kinetics,a crystallization technology for chlorantraniliprole was developed by exploring the influence of operating factors including solvent composition,water content of soluble content,stirring rate,crystallization temperation and crystal growth time:use dimethylformamide as solvent and methanol solution as soluble agent,the volume ratio of which 5,with strring rate 90rpm;crystallization temperature 20? and crystal growth time 5h.Under such operating factors,the chlorantraniliprole obtained had a purity up to 99.3% and a recovery rate up to 85%,with a clear crystal shape,characterization methods of which included High Performance Liquid Chromatography,Scanning Electron Microscopy,and Differential Scanning Calorimetry.