针对铬矿主次组分同时测定中存在的问题,建立了熔融制样-X射线荧光光谱法同时测定铬矿中Cr2 O3、Fe、MgO、SiO2、Al2 O3、CaO、P、S、K2 O、Ni、Co、Ti、Mn、V等14种主次组分的分析方法.以Li2 B4 O7-LiBO2(m:m=67:33)为熔剂,稀释比1:20,定量加入氧化-脱模混合溶液(500g/L NaNO3溶液-70g/L LiBr溶液),在700℃ 预氧化5min,在1100℃熔融20 min,制得透明的熔片.使用铬矿标准物质与钒钛铁精矿标准物质,光谱纯试剂氧化镍按不同比例混合制备合成校准样品系列,拓展了校准曲线含量范围.方法的检出限为10~748μg/g.采用理论α系数法和经验系数法相结合的方法校正基体效应.对1个铬矿样品进行精密度考察,测定结果的相对标准偏差(RSD,n=12)均小于5%;采用实验方法对1个铬矿标准物质进行分析,测定结果与认定值相符,能满足铬矿中各成分的检测要求.%Aiming at the problems in simultaneous determination of major and minor components in chromite ,the simultaneous determination method of 14 major and minor components in chromite (including Cr2 O3 ,Fe ,MgO ,SiO2 ,Al2 O3 ,CaO ,P ,S ,K2 O ,Ni ,Co ,Ti ,Mn and V) by X-ray fluorescence spectrometry with fusion sample preparation was established .Li2 B4 O7-LiBO2 (m : m = 67 : 33) was used as flux with dilution ratio of 1 : 20 .The oxidation-releasing mixture (500 g/L NaNO3 solution-70 g/L LiBr solution) was added quantitatively .The sample was pre-oxidized at 700 ℃ for 5 min and then fused at 1100 ℃ for 20 min .The as-prepared sample piece was transparent .The synthetic calibration sample series were prepared using certified reference materials of chromite , vanadium-titanium-iron concentrate and spectrum pure nickel oxide with different ratios .The content range of calibration curve was expanded .The detection limit of method was 10-748 μg/g .The matrix effect was corrected by theoretical α coefficient method and empirical coefficient method .The precision test was conducted with one chromite sample .The relative standard deviations (RSD , n = 12) of determination results were all less than 5% .The proposed method was applied for the analysis of one certified reference material of chromite ,and the results were consistent with the certified values .The proposed method could meet the detection requirements of components in chromite .
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