硅钼蓝分光光度法测定镁钕合金中硅  

Determination of silicon in magnesium-neodymium alloy by silicon molybdenum blue spectrophotometry

作　　者：于亚辉[1,2] 张翼明[1,2] 王东杰[1,2] 金文莉[1,2] 

机构地区：[1]包头稀土研究院,内蒙古包头014030 [2]稀土冶金及功能材料国家工程研究中心,内蒙古包头014030

出　　处：《冶金分析》2016年第5期49-52,共4页Metallurgical Analysis

摘　　要：采用盐酸（1＋2）溶解镁钕合金样品，在O．12～O．25mol／L盐酸介质中，加入2．5mL50a／L钼酸铵溶液与硅形成硅钼黄络合物，稳定15rain后，加入5mL10a／L硫酸-草酸混合酸分解磷、砷钼杂多酸，而后加入2．5mL10a／L抗坏血酸溶液做还原剂，使硅形成稳定的硅钼蓝络合物，稳定15min后，于分光光度计波长800nm处测量其吸光度，从校准曲线上查得硅量，从而建立了使用分光光度法测定镁钕合金中硅的方法。结果表明，试液中硅质量在1～5Oμg范围内与吸光度呈线性，校准曲线线性回归方程为y=61．634x＋0．0075，相关系数r=1．000；方法中硅的检出限为0．00011％（质量分数）。按照实验方法对镁钕合金样品中硅进行加标回收试验，回收率为97％～104％。实验方法用于测定镁钕合金实际样品中硅，结果的相对标准偏差（RSD，n=11）为O．76％～7．6％，结果与电感耦合等离子体原子发射光谱法（ICP-AES）测定结果相吻合。The magnesium-neodymium alloy sample was dissolved with hydrochloric acid(1+2).In 0.12-0.25mol/L hydrochloric acid medium,2.5mL of 50g/L ammonium molybdate solution was added.It reacted with silicon to form silicon molybdenum yellow complex.After stabilizing for 15 min,5mL of 10g/L sulfuric acid-oxalic acid mixed acid was added to decompose phosphorus and arsenic-molybdenum heteropolyacid.Then,2.5mL of 10g/L ascorbic acid solution was added as reducing agent to form stable silicon molybdenum blue complex.After stabilizing for 15 min,the absorbance was measured at 800 nm on spectrophotometer.The content of silicon could be obtained according to the calibration curve.The determination method of silicon in magnesium-neodymium alloy by spectrophotometry was established.The results showed that the mass of silicon in range of 1-50μg was linear to the absorbance.The linear regression equation of calibration curve was y=61.634 x+0.007 5with correlation coefficient of r=1.000.The detection limit of silicon in this method was 0.000 11%(mass fraction).The recovery test of silicon in magnesium-neodymium alloy was conducted according to the experimental method.The obtained recoveries were between 97% and104%.The proposed method was applied to the determination of silicon in actual sample of magnesium-neodymium alloy.The relative standard deviations(RSD,n=11)were between 0.76% and 7.6%.The found results were consistent with those obtained by inductively coupled plasma atomic emission spectrometry(ICP-AES).

关 键 词：分光光度法 镁钕合金 硅 

分 类 号：TG115.33[金属学及工艺—物理冶金]