文献类型：期刊文献

中文题名：湿法磷酸脱氟渣回收技术研究

英文题名：Study on recycling of the fluoride residue from wet-process phosphoric acid

作者：钟文婧[1];纪利俊[1];付全军[2];盛勇[2];朱家文[1]

机构：[1]华东理工大学化工学院,上海200237;[2]中化化肥有限公司成都研发中心,四川成都610000

年份：2019

卷号：47

期号：1

起止页码：70

中文期刊名：化学工程

外文期刊名：Chemical Engineering(China)

收录：CSTPCD;;Scopus;北大核心:【北大核心2017】；CSCD:【CSCD_E2019_2020】；

语种：中文

中文关键词：脱氟渣;氟硅酸钠;硫酸;资源回收

外文关键词：defluorination residue;sodium fluosilicate;sulfuric acid;resources recovery

摘要：脱氟渣是湿法磷酸化学净化过程中产生的固体废渣,其主要成分为氟硅酸钠,并夹带大量磷酸。为实现脱氟渣的资源化利用,本文研究了硫酸分解Na_2SiF_6的反应特性和脱氟渣的酸解回收工艺。考察了浓硫酸分解氟硅酸钠反应中,酸浓度、H_2SO_4与Na_2SiF_6摩尔比、反应温度、反应时间对氟硅酸钠分解率的影响,得到最优工艺条件为:H_2SO_4与Na_2SiF_6摩尔比为2.6、硫酸质量分数为98%、反应温度140℃、反应时间1 h。在此基础上,用浓硫酸分解脱氟渣,酸解处理后脱氟渣分解率达到98%以上,酸解残渣主要成分为硫酸氢钠。以酸解残渣作为脱氟剂,对湿法磷酸脱氟,脱氟率达到82.8%。文中脱氟渣酸解工艺可满足饲钙生产需要,实现了磷酸回收和钠资源循环利用。
The fluoride residue is a solid waste produced in chemical defluorination of wet-process phosphoric acid production.Fluoride residue contains mainly sodium fluorosilicate accompanied with phosphoric acid.In order to utilize the fluoride residue as useful resource,decomposition of sodium fluorosilicate with sulfuric acid and recovery process of fluoride residue by acid decomposition were studied in this paper.The effect of sulfuric acid concentration,molar ratio of H2SO4 to Na2SiF 6,reaction temperature and time on decomposition ratio of Na 2SiF 6 were investigated,and the optimized reaction conditions obtained were as follows:sulfuric acid mass fraction 98%,molar ratio of H2SO4 to Na2SiF6 2.6,reaction temperature 140℃,reaction time 1 h.On the basis of above research,sulfuric acid was used to decompose fluoride residue,and the defluorination ratio reached over 98%.The acidolysis residue consisting mainly of sodium bisulfate was used in defluorination of wet process phosphoric acid,the defluoridation ratio reached 82.8%.The acid decomposition process of fluoride residue can meet the needs of monocalcium phosphate production and recover the resources of phosphorus and sodium in fluoride residue.