电位滴定法测定冷轧含铬污泥中氯离子含量  

Determination of chloride ion content in cold-rolled chromiumcontaining sludge by potentiometric titration

作　　者：董礼男 张继明 赵希文 朱春要 Dong Linan;Zhang Jiming;Zhao Xiwen;Zhu Chunyao(Institute of Research of Iron and Steel,Jiangsu Province/Sha-Steel,Zhangjiagang 215625,China)

机构地区：[1]江苏省(沙钢)钢铁研究院,江苏张家港215625

出　　处：《电镀与精饰》2024年第11期113-119,共7页Plating & Finishing

摘　　要：冷轧含铬废水经过一系列化学反应、沉淀、压滤后产生的固体废弃物称为冷轧含铬污泥。其主要成分有铬的化合物、有机物及少量铜、铁、锌、镍及氯等杂质元素。近几年,国家提出针对固废资源环保处理并充分回收利用的政策,因此,准确测定有害元素氯离子含量对含铬污泥的后续处理具有重要的指导意义。样品经高温灼烧、酸消解后,可消除各类难溶物的干扰,加碱液生成沉淀,过滤后得到的滤液,以消除共存元素铬对氯离子检测的干扰,采用硝酸银标准滴定溶液进行电位滴定。建立了电位滴定法测定含铬污泥中氯离子含量的方法,讨论了灼烧温度、消解酸、共存元素对氯离子检测的影响。确定了在800℃进行高温灼烧,分别加入15 mL硝酸、10 mL硫酸、5 mL过氧化氢对样品进行消解,加入碱液生成沉淀,得到的滤液酸化后进行仪器测定。结果表明:在仪器最佳滴定条件下,方法的检出限为0.0022%,按照本实验方法对含铬污泥中氯离子含量进行测定,检测结果的相对标准偏差(RSD,n=10)小于2.00%,加标回收率在98.30%~101.70%之间。Cold rolling chromium-containing sludge isthesolidwastecausedbya series of chemical reactions,precipitation,and filtration of cold rolling chromium containing wastewater.It contains chromium compounds,organic compounds and less copper,iron,zinc,nikle and chlorine.Accurately measuring the content of harmful elements such as chloride ions has important guiding significance for the subsequent treatment of chromium containing sludge because of the government has proposed policies for environmental protection treatment and full recycling of solid waste resources in recent years.Determination of chloride ion content in chromium-containing sludge by potentiometric titration method was established that the sample is added with alkaline solution to form a precipitate after hightemperature burning and acid digestion.The resulting filtrate is acidified and placed in a potentiometric titrator for potentiometric titration using silver nitrate standard titration solution.The sample hightemperature burning,digestion acid,aging time and titration conditions on chloride ion detection were discussed.The results show that high-temperature burning at 800℃,15 mL nitric acid,10 mL sulfuric acid,and 5 mL hydrogen peroxide to digest the sample,added alkaline solution to form precipitate,and the resulting filtrate was acidified before instrument measurement.Under the optimized working condition of instrument,the detection limit of method was 0.0022%.According to the test method,the relative standard deviations(RSD,n=10)of chloride ion content in cold-rolled chromium-containing sludge was less than 2.00%,and the recoveries were 98.30%‒101.70%.

关 键 词：冷轧含铬污泥 氯离子 电位滴定法 

分 类 号：X830[环境科学与工程—环境工程]