锡精矿苏打还原焙烧样品中锡的物相分析方法探讨  

Discussion on phase analysis method of tin in soda reduction roasting sample of tin concentrate

作　　者：罗文波 张琼[1] 周东波 洪开发 谢瑶 郑凯 LUO Wenbo;ZHANG Qiong;ZHOU Dongbo;HONG Kaifa;XIE Yao;ZHENG Kai(Faculty of Materials and Energy Engineering,Guizhou Institute of Technology,Guiyang 550003,China)

机构地区：[1]贵州理工学院材料与能源工程学院,贵州贵阳550003

出　　处：《冶金分析》2021年第10期42-48,共7页Metallurgical Analysis

基　　金：贵州省教育厅-贵州理工学院青年科技人才成长项目(黔教合KY字[2017]222);贵州理工学院高层次人次科研启动项目(XJGC20190963)。

摘　　要：锡精矿苏打还原焙烧-浸出制备锡酸钠工艺中,为更好地明晰锡精矿还原焙烧机理及更好地控制实验条件以提高锡酸钠转化率,需明确还原焙烧试样中锡的物相。实验提出两套锡物相分析方法:方案1首先采用溴乙醇(3+97)溶剂选择性溶出金属锡,在溶出温度25℃、溶出时间20min的优化条件下,金属锡的溶出率达到97%以上,氧化亚锡、锡酸钠和二氧化锡溶出率小于1%;然后采用盐酸(1+1)选择性溶出氧化亚锡+锡酸钠,在温度25℃、时间20min的优化条件下,氧化亚锡和锡酸钠溶出率达到99%以上,二氧化锡溶出率小于3%。方案2首先采用5g/L氢氧化钠-2g/L酒石酸钠溶液选择性溶出氧化亚锡+锡酸钠,在溶出温度60℃、溶出时间20min的优化条件下,氧化亚锡和锡酸钠溶出率达到97%以上,金属锡和二氧化锡溶出率小于1%;然后采用方案1的溴乙醇(3+97)选择性溶出金属锡。两套方案锡各物相检测值的相对标准偏差(RSD)均小于3%,满足物相分析的误差要求。两套方案的正确度实验表明两个物相分析方案都是可行的,满足了锡精矿苏打还原焙烧中锡物相分析的需要。In the preparation process of sodium stannate by soda reduction roasting-leaching of tin concentrate,the phases of tin in reduction roasting sample must be explicated in order to better understand the reduction roasting mechanism of tin concentrate and better control the experimental conditions to improve the conversion rate of sodium stannate.Two methods to analyze the phase of tin were proposed in experiments.Scheme 1:metallic tin was dissolved selectively with bromoethanol(3+97)solvent.The dissolution rate of metallic tin was more than 97%under the optimal conditions,i.e.,dissolution temperature and time were 25℃and 20 min,respectively.Meanwhile,the dissolution rate of stannous oxide,sodium stannate and tin dioxide was less than 1%.Then stannous oxide and sodium stannate were dissolved selectively with hydrochloric acid(1+1)solvent.The dissolution rate of stannous oxide and sodium stannate was more than 99%under the optimal conditions,i.e.,dissolution temperature and time were 25℃and20 min.Meanwhile,the dissolution rate of tin dioxide was less than 3%.Scheme 2:stannous oxide and sodium stannate were dissolved selectively with 5 g/L sodium hydroxide and 2 g/L sodium tartrate solution.The dissolution rate of stannous oxide and sodium stannate was more than 97%under the optimal conditions,i.e.,dissolution temperature and time were 60℃and 20 min,respectively.Meanwhile,the dissolution rate of metallic tin and tin dioxide was less than 1%.Then the metallic tin was dissolved selectively with bromoethanol(3+97)solvent in Scheme 1.The relative standard deviations(RSD)of determination results of tin phases in two schemes were all below 3%,which could meet the error requirement in phase analysis.The trueness in two experiments schemes indicated that both schemes were feasible,which could meet the analysis requirements of tin phases in tin concentrate sample after soda reduction roasting.

关 键 词：物相 锡精矿 锡酸钠 金属锡 氧化亚锡 二氧化锡 苏打还原焙烧 

分 类 号：O657[理学—分析化学] TF041[理学—化学]