使用吡咯烷二硫代氨基甲酸铵(APDC)和二乙基二硫代氨基甲酸钠(DDTC)混合溶液为络合剂,以甲基异丁基酮(MIBK)为萃取剂,火焰原子吸收法测定硅粉中微量铬,既消除了共存元素的干扰,同时也提高了方法的灵敏度.该法测定的灵敏度为0.006μg·ml~(-1)/1%,相对误差小于4%,标准偏差小于0.70PPm,变动系数小于8.0%。 A mixed solution of ammonium pyrrolidine dithiocarbamate (APDC) and sodium diethyldithiocarbamate (DDTC) was used as the complexing agent and methyl isobutyl ketone (MIBK) as the extractant. Flame atomic absorption spectrometry The trace chromium in the silicon powder not only eliminates the interference of coexisting elements but also increases the sensitivity of the method.The sensitivity of the method is 0.006μg · ml -1 / 1%, the relative error is less than 4% and the standard deviation is less than 0.70PPm, the coefficient of variation is less than 8.0%.