增敏苯基荧光酮光度法直接测定五氧化二钒中微量铝

不需要预先分离基体,采用苯基荧光酮光度法直接测定了五氧化二钒中微量铝。考察了测定条件、表面活性剂的增敏作用、铁和基体钒对铝测定的干扰及干扰的消除方法。结果表明:以非离子表面活性剂吐温-80作为增敏剂显色反应的增敏效果最好,采用酒石酸钠可以消除五氧化二钒中铁离子对铝的干扰。由于钒在显色体系中随着浓度的变化吸光度呈现出线性变化规律,所以对于钒基体的干扰,提出了用平面模拟方程进行校正。校正后铝的计算值与理论值吻合较好,相对偏差在±2%以内,表明了方法是可行的。方法用于实际样品分析,铝的测定值与国家标准方法的测定值一致。方法所涉原理及计算都比较简单, 这不仅适用于实验室,也同样适用于工业流程分析。

Direct determination of micro aluminum in vanadium pentoxide by sensitivity-enhancing phenylfluorone spectrophotometry

Trace aluminum in vanadium pentoxide was directly determined by phenylfluorone spectrophotometry without separation of matrix. The determination conditions, the sensitivity-enhancing of surfactant, the interference of iron and matrix vanadium in the determination of aluminum and the elimination method were investigated. The results showed that, the sensitivity-enhancing effect of color reaction was best when nonionic surfactant Tween-80 was used as the sensitizer. The interference of iron in vanadium pentoxide in the determination of aluminum could be eliminated using sodium tartrate. The absorbance of coloring system showed linearity to the concentration of vanadium, thus the interference of matrix vanadium was corrected by plane simulation equation. The calculation values of aluminum after correction were consistent with the theoretical values. The relative deviation was within ±2%, indicating that this method was feasible. The proposed method was applied to the analysis of actual sample. The found results of aluminum were consistent with those obtained by national standard method. The principle and calculation of this method were relatively simple. it was not only applicable for laboratory, but also applicable for industrial process analysis.