EDTA容量法测定化工生产废水中钙和镁  

Determination of Calcium and Magnesium in Chemical Production Wastewater by EDTA Volumetric Method

作　　者：李焕焕 贺新利 王静 李涛涛 Li Huan-huan;He Xin-li;Wang Jing;Li Tao-tao

机构地区：[1]河南开祥精细化工有限公司,河南义马472300

出　　处：《化工设计通讯》2022年第1期164-165,168,共3页Chemical Engineering Design Communications

摘　　要：化工生产废水中测定钙镁含量时,常因水中含有铁(Ⅲ)、钛(Ⅳ)、铬(Ⅲ)、铝、锌、铜、银、镉(Ⅱ)、汞(Ⅱ)、铅、铋(Ⅲ)、镍和钴(Ⅱ)等干扰,终点颜色变化不明显,影响终点的判断,结果不准确。尤其是当样品中含铁、铝较高时,会造成指示剂的封闭,使终点不能出现。采用加入六次甲基四胺和2%铜试剂溶液掩蔽铁离子和铝离子而与钙、镁分离,测定时终点明显,测定结果准确。When determining the content of calcium and magnesium in chemical production wastewater,the color change of the end point is not obvious due to the interference of iron(III),titanium(IV),chromium(III),alu minum,zinc,copper,silver,cadmium(II),mercury(II),lead,bismuth(III),nickel and cobalt(II).Especially when the content of iron and aluminum in the sample is high,the indicator will be closed so that the end point cannot appear.In this paper,hexamethylenetetramine and 2%copper reagent solution are added to mask iron and aluminum ions and separate them from calcium and magnesium.The end point is obvious and the determination result is accurate.

关 键 词：EDTA 钙镁测定 六次甲基四胺 铜试剂 

分 类 号：O655.2[理学—分析化学]