论文部分内容阅读
建立了挥发分离-铬天青S增敏分光光度法测定巴氏合金中Al的方法。锡或铅基合金试样以HCl-HNO3或HBr-H2O2溶解,在少量H2SO4存在下,用HCl-HBr挥发Sn,Sb,在1.2 mol/L HCl中形成PbCl2沉淀,残余Sn,Pb小于0.01%或5%,于微酸性溶液中用适量Na2SO2掩蔽Cu2+,Fe3+以抗坏血酸还原。在p H 6.8乙酸-乙酸铵溶液中,Al与铬天青S及聚乙二醇辛基苯基醚生成绿色络合物。对试样分解、试剂用量、络合物稳定性、分离与回收、共存元素影响、标准曲线和HBr空白等条件进行了实验优化。Al含量在0.01~0.16μg/m L范围内符合朗伯-比尔定律,相关系数为0.99968,方法检出限(3s/k)为0.49μg/L。方法用于代表样中3.6×10-4%~9.9×10-2%Al的测定,RSD(n=11)为1.7%~7.2%,回收率为96.0%~101%。
Volatile separation - chromazurol S sensitization spectrophotometry was established for the determination of Al in Babbitt. The samples of Sn or Pb-based alloy were dissolved with HCl-HNO3 or HBr-H2O2. SnO2 and Sn were volatilized with HCl-HBr in the presence of a small amount of H2SO4 to precipitate PbCl2 in 1.2 mol / L HCl. The residual Sn and Pb were less than 0.01% Or 5%, Cu2 + is masked with an appropriate amount of Na2SO2 in a slightly acidic solution, and Fe3 + is reduced with ascorbic acid. In p H 6.8 acetic acid-ammonium acetate solution, Al forms a green complex with chrome azure S and polyethylene glycol octylphenyl ether. The conditions of sample decomposition, reagent dosage, stability of complex, separation and recovery, coexistence of elements, standard curve and blank of HBr were optimized experimentally. The Al content in the range of 0.01-0.16 μg / m L conforms to the Lambert-Beer law with a correlation coefficient of 0.99968 and the detection limit (3s / k) of 0.49 μg / L. The method was applied to the determination of 3.6 × 10-4% -9.9 × 10-2% Al in representative samples. The RSD (n = 11) was 1.7% -7.2% and the recovery was 96.0% -101%.