论文部分内容阅读
在微酸性溶液中,钒与4-(2-吡啶偶氮)间苯二酚(即PAR)形成稳定的络合物,在545nm有最大吸收,曾用于钒的分光光度测定,但许多金属离子与PAR反应而干扰测定,灵敏度不高。之后,M.Siroki等曾试验了这一有色络合物分别与氯化四苯磷及氯化四苯砷形成的一种能被三氯甲烷等溶剂所萃取的络合物[(C_6H_5)_4P~+,VO_2R~-]及[(C_6H_5)_4A_(?)~+,VO_2R~-](R~(2-)为PAR的阴离子),反应灵敏,在最大吸收波长560nm处,摩尔吸光系数各为3.9×10~4和3.8×10~4,曾用于微量钒的分光光度测定。由此,本文试验了硫酸四苯锑与VO_2R~-生成[(C_6H_5)_4S_b~+,VO_2R~-]络合物的各种化学条件,考察了络合物的性质和组成,并确立了又一种测定微量钒的萃取光度法,获得了满意的结果。
In slightly acidic solutions, vanadium and 4- (2-pyridylazo) resorcinol (PAR) form a stable complex with maximum absorption at 545 nm, which was used for the spectrophotometric determination of vanadium. However, many metals Ion and PAR reaction interference determination, sensitivity is not high. After M.Siroki et al. Had tested this colored complex respectively with tetraphenylphosphonium chloride and tetraphenyl arsenic chloride formed by a solvent such as chloroform can be extracted by the complex [(C_6H_5) _4P +, VO_2R ~ -] and [(C_6H_5) _4A _ (~) ~ +, VO_2R ~ -] (R ~ (2-) for the PAR anion), reaction sensitive, at the maximum absorption wavelength of 560nm, the molar absorption coefficient 3.9 × 10 ~ 4 and 3.8 × 10 ~ 4, used for the determination of trace vanadium spectrophotometry. In this paper, various chemical conditions of [C_6H_5] _4S_b ~ +, VO_2R ~] complexes with tetraphenylsulfuric acid and VO_2R ~ - were investigated. The properties and compositions of the complexes were investigated. A method for the determination of trace vanadium extraction spectrophotometry, obtained satisfactory results.