镁及镁合金中微量磷的测定方法研究

Study on determination method of micro-amounts of phosphorous in magnesium and its alloy

磷与钼酸铵形成磷钼杂多酸络幌物,用乙酸丁酯萃取分离,用SnCl2还原反萃取后借磷钼蓝光度法测定镁及镁合金中微量磷.在波长700nm处工作曲线线性范围0～1.5μg/mL,相关系数为0.9995,络合物表观摩尔吸光系数ε=1.45×10^4L·mol^-1·cm^-1,相对标准偏差在1.40%～3.10%之间,加标回收率在99.3%～101.0%之间,本法与ICP法相对照结果比较满意.

Micro-amounts of phosphorous and its alloy was reduced to divalent with tin（ Ⅱ ） chloride and then reacted with ammonium molybdate to form a phosphorous-molybdate complex. It was extracted with butyl ethanoate and total phosphorous in the sample was determined by phosphorous-molybdate blue spectrophotometry. Linear range is 0 - 1.5 μg/mL （ r = 0.9995） for phosphorous at the wavelength of 700 nm, the apparent molar absorptivity of complex （e） is 1.45 ×10^4 L·mol^-1·cm^-1. The recovery of the method is in the range of 99.3% - 101.0% and RSD is 1.4% -3.1%. In comparison with the results obtained by ICP, the results were satisfactory.