非均相法制备高浓碱溶液脱硅剂斜方水合碳铁酸钙的研究  

Heterogeneous synthesis of rhombic calcium hydroferrocarbanate as desilication agent in concentrated alkali solution

作　　者：洪涛[1,2] 郑诗礼[2] 张懿[2] 

机构地区：[1]西安建筑科技大学冶金工程学院,陕西西安710055 [2]湿法冶金清洁生产技术国家工程实验室,中国科学院过程工程研究所绿色过程与工程重点实验室,北京100190

出　　处：《轻金属》2009年第9期15-21,共7页Light Metals

基　　金：中国科学院知识创新工程重要方向项目(KGCX2-YW-321-2);"十一五"国家科技支撑计划课题(2006BAC02A05);国家重点基础研究发展计划(973计划)(2007CB613501)

摘　　要：提出以斜方水合碳铁酸钙为脱硅剂解决亚熔盐法处理一水硬铝石型铝土矿所得高浓碱溶出液的深度脱硅问题。采用非均相方法合成了碳铁酸钙(3CaO.Fe2O3.CaCO3.12H2O)脱硅剂,对影响合成过程的主要因素进行了考察。结果表明,适当提高合成温度、缩短合成时间可以提高水合碳铁酸钙的含量。最优合成工艺条件为:反应温度313K,反应时间16h,反应液固比25,搅拌速率500r/min,氧化钙粒度0.104mm～0.120mm。脱硅过程中,斜方晶系的水合碳铁酸钙转变为立方晶型的钙铁石榴石,在此过程中二氧化硅和少量氧化铝进入晶体结构,形成钙铁硅石榴石和钙铁铝硅石榴石,脱硅产物的铝硅比小于0.5。RhomBic Calcium HyDroferroearbonate （3CaO· Fe2O3· CaCO3· 12H2O） was synthesized by heterogeneous reaction and used as a new deailication agent in the concentrated alkali solution prepared by decomposing diasporie bauxite with KOH sub - molten salt. Effects of the reaction conditions on the synthesis of Calcium Hydroferrocarbonate were studied. The results showed that the shorter time and the higher reaction time could improve the content of Calcium Hydroferrocarhonate in the product. The optimized parameters were as follows： reaction temperature 313 K, reaction time 16 h, liquid to solid ratio of 25, stirring speed 500 r/min, and CaO particle size 0.104mm-0.120ram. In desilcalion process, Calcium Hydroferrocarbonate decomposed to cuble Calcium Hydroferrite, then formed Calcium Hydroferrosilieate and Calcium Hydroferroalumosillcate through the reaction with silica and alumina. The mass ratio of alumina to silica in the DSP （desilieation product） was less than 0.5.

关 键 词：脱硅剂 非均相合成 水合碳铁酸钙 高浓碱性溶液 

分 类 号：TF821[冶金工程—有色金属冶金]