论文部分内容阅读
铅基合金种类多,成分复杂,含有大量锑锡及其它杂质。本法在常用萃取钼蓝光度法基础上,对不同合金作了试验,在溶样上,铅锑合金用硝酸酒石酸溶解,避免了溶样和萃取过程中锑的水解。由于酒石酸与钼酸能络合,降低了有效钼酸的浓度,因此酒石酸用量需控制。方法中酒石酸用量不超过0.25g,否则结果显著偏低。磷严重干扰测定,一般铅基合金中含磷极微,可不考虑。试剂混合酸:2g酒石酸溶于150ml硝酸(1+2)中。还原溶液:溶解1g氯化亚锡于40ml浓盐酸中。取出10ml,加入178ml 0.5N硫酸,12ml正丁醇。
Many types of lead-based alloys, complex composition, contains a lot of antimony tin and other impurities. Based on the commonly used molybdenum blue photometric method, different alloys were tested. On the sample solution, the lead-antimony alloy was dissolved with tartaric nitric acid to avoid the hydrolysis of antimony during the sample-dissolving and extraction. As tartaric acid and molybdic acid can complex, reducing the effective concentration of molybdic acid, tartaric acid dosage to be controlled. Tartaric acid method does not exceed 0.25g, otherwise the result is significantly lower. Phosphorus serious interference determination, the general lead-based alloy containing phosphorus is minimal, may not be considered. Reagent mixed acid: 2 g of tartaric acid is dissolved in 150 ml of nitric acid (1 + 2). Reduction solution: Dissolve 1 g of stannous chloride in 40 ml of concentrated hydrochloric acid. 10 ml was removed and 178 ml of 0.5 N sulfuric acid and 12 ml of n-butanol were added.