【摘要】 Si和P与钼酸铵反应均能生成钼黄,为了消除P对Si的干扰,国家标准采用加草酸溶液方法,研究发现该溶液不但破坏磷钼黄,也破坏硅钼黄,且反应速度很快,比色必须在2 min内完成,否则结果大大偏低。我们也用酒石酸溶液替代草酸溶液,虽然破坏硅钼黄速度减慢,但也不理想。本文通过实验推导和验证:如果已知P浓度,把测得的Si、P总浓度减去P的浓度乘0.389所得的值,就消除了P的干扰,方法简便准确。更多还原

【Abstract】 Molybdenum-yellow can be generated when Si and P react with ammonium molybdate,and the oxalic acid solution is added to eliminate P interference in Chinese national standard method.The study showed that the solution destroys either phosphomolybdenum yellow and silicomolybdic yellow,however,the colorimetric operation must be done in 2 minutes,otherwise the results will be greatly on the low side.The ideal result is not obtained when use tartaric acid instead of oxalic acid,although destroying speed of silicomolybdic yellow was slowed down.By experimental derivation and verification,the conclusion was drawn that if concentration of P is known,the used concentration of Si subtracting P multiplied by 0.389 can reflect the P interfere dispelling and the method is convenient and accurate.更多还原