A study of significant variables and their effects on the analysis of hexavalent chromium

To determine the effect of an alkaline extraction on soluble Cr(VI), a standard addition of 0.5 μg of potassium chromate was performed on a filter, allowed to dry and then extracted with the alkaline solution. Three replicates had a 109.4% recovery. Centrifuging the filters was useful in eliminating the CO2 interference for the alkaline extraction. Also, the use of an alkaline extraction did not negatively impact the soluble Cr(VI). The positive result of the preliminary extractions resulted in further investigation of an alkaline extraction to incorporate the inclusion of both soluble and insoluble Cr(VI).