回收磷化工废液中的氟制备氟化钠

Preparation of sodium fluoride by recovering fluorine from waste liquid in phosphate chemical industry

以磷化工行业产生的含氟废液中的氟和磷酸三钠为原料制备氟化钠,考察了原料配比、反应温度、反应时间、搅拌速率对氟化钠生成量的影响。最佳工艺条件:磷酸三钠与氟化铵物质的量比为1.4,反应温度为95℃,反应时间为60 min,搅拌速率为350 r/min。在最佳条件下,用100 g废液可以制得4.02 g氟化钠,废液中氟的回收率达到85%。

Sodium fluoride was prepared with trisodium phosphate and fluorine in the waste liquid from phosphate chemical industry as raw materials. Influences of various factors, such as mix ratio of raw materials （ amount-of-substance ratio of trisodium phosphate to ammonium fluoride） ,reaction temperature, reaction time,and stirring speed, on yield of sodium fluoride were investigated. Optimum conditions were as follows ： amount-of substance ratio of trisodium phosphate to ammonium fluoride was 1.4 ,reaction time was 60 min,reaction temperature was 95 ℃ , and stirring speed was 350 r/min. Under the optimum conditions,yield of sodium fluoride was 4.02 g per 100 g waste liquid,and the recovery rate of fluorine in waste liquid reached 85%.