摘要：A convenient, quick, and accurate procedure for microdetermination of mercury contained in various kinds of materials, which can replace ordinary dithizonate colorimetry combined with wet-ashing method, was established. In this new method, the material is combusted in a platinum-coated-stainless-steel bomb which contains a solution of 20 ml of 2.0 N H2SO4 and 20 ml of 0.3% KMnO4 solution, and is filled with oxygen, and the solution of mercuric ion produced is submitted to followed determination by atomic absorp- tion spectrophotometry. Mercury in the combasted solution is converted into mercury vapor either, (1) by extraction of mercury with dithizone-benzene and subsequent heat-decomposition of the mercury dithizonate, or (2) by reduction of mercury with SnCl2. Both of these two procedures, when applied to subsequent determination of mercury by atomic absorption spectrophotometry, showed liniarity down to 0.5 μg when assayed at 253.7 mμ and sensitivity of 0.05 μg of mercury. The recovery rate of mercury contained in rice at a level of 10 ppm was 98% in average by this method. The new method was found to be applicable to various materials such as fish, rice, wheat, cabbage, hair, blood, animal organs, and solid of river or lake bed and gave better results than other procedures.
