含钙镍泥常规分析前处理方法验证

Modification and Verification of Pretreatment Method for Conventional Analysis of Nickel Slime Containing Calcium

含钙量高镍泥中镍的检测方法建立,在做电镀污泥中镍含量的检测中发现,有部分公司的污泥用行业标准《YST341.1-2006镍精矿中镍含量测定丁二酮肟沉淀分离-EDTA络合滴定法》前处理镍含量偏低,分析原因,在电镀废水处理时加入了石灰调整PH值,污泥中钙含量偏高,在前处理时要加入硫酸消解,硫酸钙微融入水,大部分以沉淀形式沉了下来,会夹带部分镍,使结果偏低;找到原因后,在前处理上做了调整,不加硫酸,用王水和高氯酸分解有机物,结果理想,相对标准偏差0.3%,加标回收率99.5%~105%满足要求。

The method of nickel detection in nickel sludge with high calcium content was established.It was found that nickel content in nickel sludge pretreated by industry standard YST341.1-2006 Nickel Concentrate Determination of Nickel Content in Dimethylglyoxime Precipitation Separation-EDTA Complexometric Titration was low.The reason was analyzed.Lime was added to adjust PH value and calcium content in sludge in electroplating wastewater treatment.When the pretreatment is carried out,sulfuric acid is added to digest,calcium sulfate is slightly mixed into water,most of which settle down in the form of precipitation,and some nickel is entrained,which results in low results.After finding out the reasons,the pretreatment is adjusted to decompose organic matter with aqua regia and perchloric acid without sulfuric acid,and the results are ideal,with relative standard deviation of 0.3%,and recovery of 99.5%~105%meeting the requirements.