摘要:
The phases in ferrovanadium before and after acid dissolution were analyzed and compared by X-ray diffraction.It was found that the main composition of residues after acid dissolution was silicon-alumi-num oxide.Therefore,the sample could be treated with mixed acid by microwave digestion technology to increase the reaction temperature at high pressure.In this study,the sample was dissolved with nitric acid-hydrochloric acid-hydrofluoric acid mixture and treated by microwave digestion with tow-step temperature rising.Si 251.611nm,Al 394.401nm,Mn 257.610nm,P 178.284nm,As 189.042nm,Cu 324.754nm and Ni 231.604nm were selected as the analytical line.The calibration curve was prepared by matrix matc-hing method to eliminate the influence of matrix effect.The simultaneous determination of silicon,alumi-num,manganese,phosphorus,arsenic,copper and nickel impurities in ferrovanadium by inductively cou-pled plasma atomic emission spectrometry(ICP-AES)with microwave digestion was established.The line-ar correlation coefficients(r)of calibration curves for testing elements were all higher than 0.9995.The detection limits of elements in this method were in range of 0.0001%-0.0013%(mass fraction).The pro-posed method was applied for the determination of silicon,aluminum,manganese,phosphorus,arsenic, copper and nickel in two ferrovanadium standard samples.The relative standard deviations(RSD,n=8)of determination results were less than 4%,and the found results were consistent with the certified values.%利用X射线衍射法对钒铁酸溶前后的物相进行对比分析,发现酸溶残渣的主要成分为硅铝氧化物,因此可以使用混酸、在高压下提高反应温度的微波消解技术处理样品.采用硝酸、盐酸、氢氟酸混合酸并使用微波消解两步升温法处理样品,选择 Si 251.611 nm、Al 394.401 nm、M n 257.610 nm、P 178.284 nm、As 189.042 nm、Cu 324.754 nm、Ni 231.604 nm为分析谱线,采用基体匹配法绘制校准曲线消除基体效应的影响,使用电感耦合等离子体原子发射光谱法(ICP-AES)同时测定硅、铝、锰、磷、砷、铜、镍,从而建立了钒铁中硅、铝、锰、磷、砷、铜、镍等杂质元素的分析方法.各待测元素校准曲线的线性相关系数 r均大于0.9995;方法中各元素检出限为0.0001% ~0.0013%(质量分数).方法应用于两个钒铁标准样品中硅、铝、锰、磷、砷、铜、镍测定,结果的相对标准偏差(RSD,n=8)不大于4%,测定值与认定值相符合.