亚甲基蓝-高碘酸钾系统催化动力学光度法测定痕量钒(V)  

Determination of trace vanadium(V) by potassium periodate-methylene blue catalytic kinetic spectrophotometry

作　　者：王洪福[1] 苏智先[2] 张素兰[2] 陈德[3] 黄萍[1] 

机构地区：[1]绵阳师范学院化学与化学工程学院,四川绵阳621000 [2]绵阳师范学院生命科学与技术学院,四川绵阳621000 [3]攀枝花钢铁有限责任公司新钢钒技术质量部,四川攀枝花617062

出　　处：《冶金分析》2010年第4期54-57,共4页Metallurgical Analysis

摘　　要：在硫酸介质中,活化剂柠檬酸存在时,于90℃的加热条件下,痕量钒（V）灵敏地催化高碘酸钾氧化亚甲基蓝褪色的指示反应。探讨了最佳实验条件,测定了动力学参数,建立了测定痕量钒（V）的新光度分析方法。研究发现,非催化反应吸光度（A0）与催化反应吸光度（A）在659 nm处的差值ΔA与钒（V）的质量浓度ρ在0.004~0.06μg/mL范围内呈良好的线性关系,检出限为1.78×10-10g/mL。该催化反应为准一级反应,反应的表观速率常数为9.03×10-4/s,表观活化能为60.92 kJ/mol。方法用于炼钢烧结矿样品中痕量钒（V）的测定,其回收率在101%~102%的范围,符合痕量分析的要求。This paper focused on the determination of trace vanadium（V） by catalytic kinetic spectrophotometric method.In this method,the vanadium（V） could catalyze the fading reaction of the potassium periodate which acted on methylene blue in medium dilute sulfuric acid with citric acid as activator and under heating at 90 ℃.Under selected experimental conditions,the absorbence difference ΔA between non-catalytic reaction system（A0） and catalytic reaction system（A） at 659 nm remained good linear relationship with quality concentration ρ of vanadium（V） in the range of 0.1-1.5 μg/25 mL and the detection limit was 1.78×10-10 g/mL.The apparent ratio constance of the reaction was 9.03×10-4 /s,and the apparent active energy was 60.92 kJ/mol.This method has been applied to the determination of trace vanadium（V） in sinter samples.Its recovery was between 101%-102% which met the requirement of trace analysis.

关 键 词：催化动力学光度法 高碘酸钾 亚甲基蓝 钒(V) 烧结矿 

分 类 号：TG115.33[金属学及工艺—物理冶金]