Kinetic Spectrophotometric Determination of Tin by Its Catalytic Effect on the Oxidation of Arsenazo M by Potassium Bromate

摘要

Based on the catalytic effect of trace tin on discoloring reaction of arsenazo M (AsA M) with potassium bromate in 0.08 mol/L sulphuric acid solution, a method for the determination of trace tin by kinetic spectrophotometry was studied. The results show that the maximum absorption of AsA M is at 540 nm and the detection limit of the method for tin is 0.22 μg/L. Beer's law is obeyed for tin in the range of determination is 0.72–10.0 μg/L. Combined with tributyl phosphate (TPB) chromatographic separation, the method has been applied to the determination of trace tin in rock samples with satisfactory results.