氢氧化钠熔融-氯化银比浊法测定铅锌矿中氯  

Determination of chlorine in lead-zinc ore by silver chloride turbidimetry affter sodium hydroxide fusion

作　　者：袁齐[1] 

机构地区：[1]中金岭南韶关冶炼厂,广东韶关512024

出　　处：《冶金分析》2014年第1期79-81,共3页Metallurgical Analysis

摘　　要：采用氢氧化钠熔融分解试样,熔渣用水煮沸浸出,冷却定容后分取上层清液,用氯化银比浊法测定氯.考察了试样与熔剂氢氧化钠的比例、试样熔解温度与时间、氯化银悬浊液中硝酸和硝酸银加入量及试样中共存的银和硫化物对测定的影响.结果表明：试样与氢氧化钠以1∶4的质量比于650℃熔融15 min即可彻底分解,同时共存的S2-被氧化而不干扰测定;常见共存元素及试样含银量小于21.4％对测定不产生干扰.校准曲线线性范围为0～10μg/mL,相关系数为0.999,表观摩尔吸光系数为1.21×103 L·mol-1·cm-1.对铅锌矿实际样品进行分析,结果的相对标准偏差（n=7）在1.4％～2.2％范围内,测定值与硫氰酸汞分光光度法基本一致.Sample was fused with sodium hydroxide,and the slag was leached out in boiling water,before the supernatant was split after it cooled off and brought to the constant volume,and then chloride was determined by silver chloride turbidimetry.The ratio between the sample and the flux of sodium hydroxide,the sample melting temperature and time,the added amounts of nitric acid and silver nitrate in the suspension of silver chloride and the coexisting silver and sulfides in the sample in terms of their influence on the determination were investigated.The results showed that：when the sample was melted with sodium hydroxide in a 1 ∶ 4 mass ratio at 650 ℃ for 15 min,it could melt completely,and the coexisting S2-was oxidized with no interference with the determination.Common coexisting elements,and the sample contained less than 21.4 ％ silver,didn＇t interfere with the determination.The linear range of the calibration curve was 0-10 μg/mL,the correlation coefficient was 0.999,and the apparent molar absorption coefficient was 1.21 × 103 L · mo1-1 · cm-1.The actual lead-zinc ore samples were analyzed and the relative standard deviation of the results （n =7） was in the range from 1.4％ to 2.2 ％,so the measured values were consistent with those obtained by mercuric thiocyanate spectrophotometry.

关 键 词：氯 铅锌矿 碱融 氯化银比浊法 

分 类 号：P575[天文地球—矿物学]