氟罗里硅土微柱分离富集-分光光度法测定锑

Determination of antimony by spectrophotometry after separation and concentration with Florisil microcolumn

以处理过的氟罗里硅土为微柱吸附材料,采用流动注射技术进行锑的分离富集,系统地考察了氟罗里硅土微柱对Sb(Ⅲ)的吸附性能,探讨了溶液的pH值、试样流速、试样体积、洗脱液浓度和用量以及干扰离子等因素的影响。实验结果表明,pH值为5.0,试样流速为1.5 mL/min时,氟罗里硅土对Sb(Ⅲ)具有良好的吸附性能,吸附率接近99%,动态饱和吸附容量为6.76 mg/g;选用5 mL 5 mol/L NaOH溶液可将吸附的Sb(Ⅲ)完全洗脱。本法的检出限(3σ)为0.085μg/mL,相对标准偏差为RSD=0.85%(n=11,ρ=10 mg/L)。将本法应用于实际样品中锑的测定,结果满意。

A new method using a microcolumn packed with Florisil as solid-phase extractant has been developed for the determination of Sb（Ⅲ） by spectrophotometry with flow injection technique.The adsorption property of Florisil microcolumn to Sb（Ⅲ） was systematically investigated,and the effects of pH,flow rate and volume of sample solution,concentration and dosage of elution solution and interference ions were discussed.The results showed that Florisil had good adsorption property to Sb（Ⅲ） at pH 5.0 with adsorption rate close to 99 % and dynamic saturation adsorption capacity of 6.76 mg/g when the flow rate of sample solution was 1.5 mL/min.The adsorbed Sb（Ⅲ） could be fully eluted with 5 mL of 5 mol/L NaOH solution.Detection limit（3σ） of this method for Sb（Ⅲ） was 0.085 μg/mL with relative standard deviations of 0.85 %（n=11,ρ=10 mg/L）.The proposed method has been applied to the determination of trace amount of Sb（Ⅲ） in actual samples with satisfactory results.