NaPO_3用于粗锑火法精炼过程除铅  

Lead removal from crude antimony in the pyrometallurgical refining process by using NaPO_3

作　　者：叶龙刚[1] 杨声海[1] 唐朝波[1] 唐谟堂[1] 

机构地区：[1]中南大学冶金与环境学院,长沙410083

出　　处：《工程科学学报》2015年第11期1429-1433,共5页Chinese Journal of Engineering

基　　金：国家自然科学基金资助项目(51234009;51104128)

摘　　要：针对传统粗锑精炼工艺中除铅的难题,提出用Na PO3作为除铅剂,生成磷酸盐渣浮于锑液表面除去的方法.用热重-差热法和X射线衍射技术研究反应机理并进行粗锑除铅的条件实验.研究发现,Pb O与Na PO3在590℃时即开始吸热反应,在850℃以下主要形成Na Pb4(PO4)3,而在850℃以上主要形成Na Pb PO4,反应彻底.Pb O、Sb2O3和Na PO3混合物的反应表明:在Na PO3量不足时,优先与Pb O反应,只有当Na PO3足量时才会与Sb2O3生成锑的非晶态玻璃.用Na NO3作为氧化剂,在氮气保护下进行了除铅单因素实验,考察反应时间和温度、Na PO3和Na NO3加入量对结果的影响.在最优条件下精锑含铅0.047%,除铅率98.90%.In order to solve the problem of lead removal from crude antimony in the traditional antimony refining process,Na PO3 was introduced as a lead elimination reagent to generate phosphate slag and the slag was removed by floating on the surface of liquid antimony. The reaction mechanisms were clarified by thermogravimetric-differential thermal analysis and X-ray diffraction analysis and removal of Pb from crude Sb was investigated by condition experiment. It is found that Pb O and Na PO3 begin an endothermic reaction at 590 ℃ and mainly form Na Pb4（ PO4）3and Na Pb PO4 below 850 ℃ and above 850 ℃,respectively. The reaction products of the mixture of Pb O,Sb2O3 and Na PO3 show that Na PO3 preferentially reacts with Pb O when Na PO3 is insufficient,and amorphous antimony glass will generate only with enough Na PO3. Single-factor experiments were taken with Na NO3 as an oxidizing agent under nitrogen.Reaction time,temperature,Na PO3 and Na NO3 amounts were considered for smelting results. Under the optimal condition,the content of lead in refined antimony is 0. 047% and 98. 90% of lead is removed.

关 键 词：锑冶金 偏磷酸钠 精炼 除铅 

分 类 号：TF818[冶金工程—有色金属冶金]