磷钼蓝光度法快速测定碳素结构钢中磷的改进

Improvement of Phosphorus Molybdenum Blue Spectrophotometry Used for Rapid Determination of the phosphorus in Carbon Constructional Steel

试样以稀硝酸溶解后,用高锰酸钾氧化磷为磷酸,然后加入钼酸铵-酒石酸钾钠溶液与磷酸生成磷钼酸络离子,在氟化钠存在下,氯化亚锡溶液将其还原为磷钼蓝后,迅速加入氢氧化钠溶液降低酸度,以提高磷钼蓝色泽的稳定性。光度法线性好,相对标准偏差小于2.1369%,满足了炼钢生产的需要。

After the sample was solved with dilute nitric acid,the phosphorus was oxidized to phosphate with potassium permanganate,and adding ammonium molybdate -tartaric acid solution to form phosphomolybdic acid complex ion. With the existence of sodium fluoride,stannous chloride solution deoxidized it to phosphorus molybdenum blue. At this time,sodium hydroxide solution was added to reduce the acidity and improve the complex s stabilization. The photometry had good linear and the relative standard deviation was less than 2.136 9%, satisfying the steel production.