甲基异丁酮萃取-间接火焰原子吸收光谱法测定锑锭中磷

Determination of phosphorus in antimony slab by methyl isobutyl ketone extraction-indirect flame atomic absorption spectrometry

研究了甲基异丁酮（MIBK）萃取-火焰原子吸收光谱法间接测定锑锭中磷的分析方法。在0．01～1．0mol／L盐酸介质中，用酒石酸钾钠掩蔽锑，磷酸根与钼酸铵形成磷钼杂多酸，以甲基异丁酮为萃取试剂，火焰原子吸收光谱法测定有机相中磷钼杂多酸中钼。考察了萃取条件及钼酸铵浓度等因素的影响。在优化的实验条件下，当磷的含量在0．03～1．0mg／L范围内时，其吸光度与磷量呈良好的线性关系，方法的栓出限为0．011mg／L。对4个样品进行测定的回收率在97．9％～104．0％之间，RSD为2．0％～3．8％。

The analysis method for indirectly determination of phosphorus in antimony slab by methyl isobutyl ketone （MIBK） extraction-flame atomic absorption spectrometry was investigated. In 0.01- 1.0 mol/L HCl medium and using potassium sodium tartrate to mask antimony, phosphate radical reacts with ammonium molybdate to form a phosphorus-molybdenum heteropoly acid and then extracted by MIBK. Molybdenum of phosphorus-molybdenum heteropoly acid in organic phase was determined by flame atomic absorption spectrometry （FAAS）. The effects of extraction conditions and concentration of ammonium molybdate on determination were investigated. The results showed that the linearity between its absorbance and the concentration of phosphorus was 0.03-1.0 mg/mL. The detection limit of this method was 0. 011 mg/L. The method has been applied to the determination of trace phosphorus in antimony with recovery of 97.9% -104.0% and RSD of 2.0%-3.8%.