Simple and simultaneous determination of EDTA and general heavy metals in wastewater
CHENG Yan 1,ZHANG Xiang-yu 2 (1.Mudanjiang Medical College, Mudanjiang 157000,China; 2.College of Chemistry and Chemical Engineering,Heilongjiang University,Harbin 150001,China)
In the waste water polluted by EDTA and heavy metals, it is difficult to determination of its content by simple method because of complex formed. A new method is proposed as follows: In the presence of strong acid and aid-extraction complexing agents EDTA can be separated from EDTA-metal complex. The heavy metals are extracted to the organic phase by the ion association extraction and total amount of EDTA is analysed with spectrophotometry. Take a replicate sample and add EDTA standard solution of excess and fixed quantity to the sample, then carry out the back titration. The total content of heavy metals can be calculated by ingenious combination of extraction and back titration. This method is characterized in simpleness and time-saving without expensive instruments and specially adequate to determination of waste water polluted by EDTA and (or ) heavy metals.
【CateGory Index】： X832