ZHANG Jinxiang, CAO Jieyu, DENG Yuqiang, et al. AN APPROACH TO DETERMINATION OF FREE EDTA CONCENTRATION DURING CHEMICAL CLEANING[J]. Thermal power generation, 2011, 40(9): 45-48.
ZHANG Jinxiang, CAO Jieyu, DENG Yuqiang, et al. AN APPROACH TO DETERMINATION OF FREE EDTA CONCENTRATION DURING CHEMICAL CLEANING[J]. Thermal power generation, 2011, 40(9): 45-48.DOI:
化学清洗中游离EDTA浓度测定探讨
摘要
验证了DL/T 794—2001中游离EDTA浓度的测定方法
表明该方法不适用于EDTA化学清洗过程中游离EDTA浓度的测试
但可用于EDTA原料纯度的测定。针对EDTA化学清洗过程中游离EDTA
提出一种以二甲酚橙为指示剂
pH值≈6.0的乙酸-乙酸钠作为缓冲溶液的测试方法。该方法测定结果的相对标准偏差较小
精密度较高
更适用于新建锅炉采用EDTA化学清洗时清洗液中游离EDTA浓度的测试。
Abstract
The determination mehod of free EDTA concentration specified in standard DL/T 794—2001 has been verified.It shows that the said method isn't suitable to testing the free EDTA concentration in the process of chemical cleaning
however
it can be used to determine the purity of EDTA as a raw material.Directing against the free EDTA in the process of EDTA chemical cleaning
a test method using acetic acid-sodium acetate as the buffer solution
and taking xylenol orange as the indicator with pH value≈6.0 has been put for ward.The results of determination using the above-mentioned method have smaller relative standard deviation and higher precision
being more suitable to test the free EDTA concentration in the cleaning liquid during EDTA chemical cleaning for newly constructed boilers.