Usage On HCl In A Mother Liquid From A Fire Retardant Material Production

A large amount of mother liquor containing HCl is produced during the production of a flame retardant,and the mother liquor contains benzene,direct emissions will cause environmental pollution and waste of resources,so it is necessary to treat the flame retardant mother liquor.Many studies have been done on the treatment of waste hydrochloric acid at home and abroad.In this paper,FeCl₃was prepared by the oxidation-evaporation crystallization method using HCl in the flame retardant mother liquor as coagulant,the coagulation effect of FeCl₃ coagulant on other wastewater was further discussed,and the effect of benzene on the preparation of FeCl₃ was studied.The experiment was carried out with a pre-prepared mass fraction of 15%,20%,25%and 32%HCl solution to simulate the mother liquor,the optimum conditions for preparing FeCl₃ were investigated at 50?60 and 70?.The optimum conditions is60?,the mass fraction of HCl in the solution was 32%.The mass fraction of FeCl₃ in FeCl₃ which has been prepared was 83.3%.Further optimization of the experiment,the mass fraction of FeCl3 in FeCl3 prepared was 91.2%,the volatilization of HCl decreased by 44.2%.The simulation experiment results after adding benzene showed little effect on the purity of FeCl₃.Finally,the prepared FeCl₃ is used as a coagulant to coagulate the flame retardant wash water,the turbidity of the wash water was reduced from 25.35 NTU to 2.40 NTU,a decrease of 90.5%.In summary,in this experiment,FeCl₃ was successfully prepared by using the mother liquor in the flame retardant production process,and obtained the best experimental program.Finally,it achieve the effect of waste water recycling.