Abstract:

Ammonium ceric sulfate-mercurous nitrate system catalysis colorimetric method for determination of trace gold was restudied by fixed time and absorption spectrophotometry，and under the experimental conditions the catalytic reaction constant K value was determined.Meanwhile，we also tried without color again using the K value，which was calculated under the condition of the amount of gold that was four times of the original method，indicating effectively expands the range of measurement of gold.The method was employed to determine the national level standard material of gold，and the result was in accordance well with the recommended value.Additionally，using plasma mass spectrometry and the provisions as control sample analysis，the determination results conformed to the requirements of the industry standard.

Key words: catalytic colorimetric method, plasma mass spectrometry, precision, detection limit, analysis and testing, gold