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在已有的采用碱性熔融‐电位滴定法测定铜精矿中氯方法的基础上，提出了在加热电磁搅拌器上直接用水溶解样品，过滤沉淀后，采用电位滴定法测定样品中氯含量的方法。实验表明：称取1.000 g试样，用约40 mL水在恒温加热磁力搅拌器上于110℃均匀搅拌90 min溶解，取下，用定性快速滤纸过滤，滤液洗至用硝酸银溶液检验无氯离子；控制所得滤液体积为50mL ，再向其中加入22mL乙醇、4滴硝酸（1＋50），以硝酸银标准溶液为滴定液，可实现电位滴定法对样品中氯的测定。干扰试验表明，铜精矿样品中的共存元素不干扰氯的测定。采用实验方法对铜精矿实际样品进行精密度和加标回收试验，结果表明，测定结果的相对标准偏差（RSD ，n＝5）为1.5％～8.6％，加标回收率为94％～99％。采用实验方法对铜精矿标准样品进行测定，4次平行测定的结果与认定值之间的误差均在允许误差范围内。采用实验方法和离子色谱法对3个铜精矿样品进行方法对照试验，结果表明，两种方法的测定值基本吻合。

In existing method ,the content of chlorine in copper concentrate was determined by potentiomet‐ric titration after alkali fusion .Based on this ,a new determination method of chlorine in sample by poten‐tiometric titration was proposed .The sample was directly dissolved with water on electromagnetic stirrer by heating .After filtration ,the content of chlorine was determined .1.000 g of sample was dissolved in a‐bout 40 mL of water on constant temperature electromagnetic stirrer at 110 ℃ for 90 min .Then ,it was filtered with rapid qualitative filter paper .The filtrate was rinsed until there was no chlorine ion which was examined with silver nitrate solution .The volume of filtrate was controlled at 50 mL .Then ,22 mL of ethanol and 4 drops of nitric acid (1+50) were added .Finally ,the content of chlorine was determined by potentiometric titration using silver nitrate standard solution as titrant .The interference test showed that the coexisting elements in copper concentrate sample did not interfere with the determination of chlorine . The precision and recovery tests of actual copper concentrate sample were conducted according to the ex‐perimental method .The results indicated that the relative standard deviations (RSD ,n=5) were between 1.5% and 8.6% ,and the recoveries were between 94% and 99% .The proposed method was applied to the determination of copper concentrate certified reference material .The error between found results of four parallel determinations and certified values was within the range of allowable error .Three copper con‐centrate samples were determined by proposed method and ion chromatography for comparison .The re‐sults showed that the determination values of two methods were basically consistent .