碘量法测定硼氢根浓度及主要影响因素

基于硼氢化钠在工业应用过程中含量难以精准检测的问题,提出了碘量法测定溶液中硼氢根的浓度。通过正交实验优化了滴定工艺参数,得出测试的最佳工艺条件为：溶液酸度为0.06 mol/L,碘化钾加入量为理论值的3倍,水封暗放时间为5~10 min,指示剂用量为2.0 mL;明确了各因素对滴定结果影响的显著性顺序由大到小依次为：溶液酸度、指示剂加入量、碘化钾加入量、水封暗放时间;在最佳工艺条件下进行了优化实验,结果表明滴定过程中回收率接近100%,相对标准偏差仅约为0.3%。

Determination of BH4- concentration by iodometry and main influencing factors

Iodometry was proposed to determine BH₄^- concentration in the solution corresponding to the difficulties in precision detection of sodium borohydride during its industrial applications.Orthogonal testes were carried out to optimize the titration parameters,and the optimal conditions were obtained as follows: solution acidity was 0.06 mol/L,KI addition amount was three times theoretical value,water-sealing holding time was 5~10 min and indicator amount was 2 mL.Significances of varied influencing factors were in descending order: solution acidity,indicator addition amount,KI addition amount and water-sealing holding time.Optimization experiment was conducted under optimal conditions,and the results showed that the recovery rates were nearly 100% and the relative standard deviations were approximately 0.3% during the titration process.