Abstract:Sample was fused with sodium hydroxide, and the slag was leached out in boiling water, before the supernatant was split after it cooled off and brought to the constant volume, and then chloride was determined by silver chloride turbidimetry. The ratio between the sample and the flux of sodium hydroxide, the sample melting temperature and time, the added amounts of nitric acid and silver nitrate in the suspension of silver chloride and the coexisting silver and sulfides in the sample in terms of their influence on the determination were investigated . The results showed that: when the sample was melted with sodium hydroxide in a 1∶4 mass ratio at 650 ℃ for 15 min, it could melt completely, and the coexisting S2- was oxidized with no interference with the determination. Common coexisting elements, and the sample contained less than 21.4 % silver, didn’t interfere with the determination. The linear range of the calibration curve was 0-10 μg/mL, the correlation coefficient was 0.999, and the apparent molar absorption coefficient was 1.21 × 103 L·mol-1·cm-1. The actual lead-zinc ore samples were analyzed and the relative standard deviation of the results (n = 7) was in the range from 1.4% to 2.2 %, so the measured values were consistent with those obtained by mercuric thiocyanate spectrophotometry.