火焰原子吸收法测定铬质引流砂中铁镁含量

建立了火焰原子吸收光谱法连续测定铬质引流砂中铁、镁含量的分析方法。试样以碳酸钠-硼酸混合熔剂熔融,以盐酸浸取,在校准溶液中加入重铬酸钾和二氧化硅进行基体匹配,抵消基体影响。对熔剂、熔融温度等进行讨论,确立了最佳分析条件,对样品多次测定,其测定结果与国家标准测定方法测定的结果基本一致,相对标准偏差(RSD,n=11)小于0.3%,加标回收率在98.7%~101%。方法具有操作简便、准确性好、速度快、成本低等特点。

Determination of iron and magnesium in chromite-based stuffing sand by flame atomic absorption spectrophotometry

A rapid method was developed for the determination of iron and magnesium in chromite-based stuffing sand by flame atomic absorption spectrophotometry. The sample was prepared by melting method, using Na₂CO₃ and HBO₃ as flux. The residue was dissolved with HCl and SrCl₂ was added as releaser to eliminate the influence of the co-existing elements. The matrix effect was corrected by adding potassium dichromate and silica. The choice of flux, melting temperature, dilution ratio were attempted and optimized. A number of parallel determinations on iron and magnesium of chromite-based stuffing sand were carried out by this method. The results were consistent with the reference values using the national standard method. The relative standard deviations (RSD,n=11) were less than 0.3% and the recovery was between 98.7%-100.7%. Compared with the national standard method, the proposed method has more advantages such as operating easily, good accuracy, rapid procedure and low cost, etc..