rubeanic-acid and thiocyanic-acid

Diffuse reflectance spectroscopy can be successfully used for the quantitative determination of small amounts of pollutants like metals. The remission function was found to be linearly proportional to the concentration, when we applied the Kubelka-Munk equation. The color reactions of Cu(II), Co(II), and Ni(II) with dithiooxamide, were realised on filter paper. Reaction between Fe(III) and ammonium thiocyanate was realized on filter paper and gelatine matrix. All measurements were accomplished with a laboratory-constructed reflectometer. We have obtained a calibration curve by plotting the optical density of reflectance A(R) vs log of the mol l(-1) concentration. Limits of detection at the 10(-4) M level were estimated for all the compounds. Linear dynamic range extend over one order of magnitude and shows the potential of device for the quantitative analysis of environmental pollutants.

Topics: Cations; Cobalt; Copper; Evaluation Studies as Topic; Gelatin; Indicators and Reagents; Iron; Nickel; Paper; Reproducibility of Results; Sensitivity and Specificity; Spectrophotometry; Thioamides; Thiocyanates; Water