【摘要】 用二乙基硫代氨基磺酸钠 (Na DDTC)作为螯合剂的流动注射在线配合 C1 8固相萃取预富集联用火焰原子吸收测定体系 ,在线分离测定水体中的 Cr( ) ,分析试样速率为 5 0个 / h,对含 Cr( ) 0 .0 2 mg/ L 和 0 .15 mg/ L 的标准溶液进行 8次平行测定 ,其相对标准偏差分别为 6.90 %和 2 .18% ,相对误差为 2 .11%～ 4.75 % ,方法检测限为 4.92μg/ L。富集时间为 40 s,与直接进样比较 ,灵敏度提高 8倍。 Cr( )的含量即使达到 10 mg/ L也不影响测定更多还原

【Abstract】 Flame atomic absorption spectrometry method coupled with on\|line flow separation of Cr(Ⅵ) and preconcentration of (Ⅵ) was used to determine Cr(Ⅵ). Sodium diethyldithiocarbamate was used as the complexing agent and C\-\{18\} boned silica reversed\|phase sorbent as the column material. The optimum conditions for sorbent extraction of (Ⅵ) were evaluated. A 8\|fold enhancement in sensitivity compared with direct introduction samples was achieved after preconcentration for 40 s and sample throughput of 50 samples /h was obtained. The detection limit was 4.92 μg/L with relative standard deviation of 2.18%～6.90%. The mean relative errors for standard material determination were 2.11%～4.75%, the interference of Cr(Ⅲ) was not found even the Cr(Ⅲ) concentration of 10 mg/L.\;更多还原