【摘要】 在pH6.0～6.3的六次甲基四胺 HCl缓冲溶液中,铝 邻苯二酚紫(PCV)络合物在580nm和448nm处有正负两个吸收峰,据此建立了痕量铝的双峰双波长吸光光度法,铝在0～6μg/25ml浓度范围内遵守比耳定律,摩尔吸光系数为9.51×104L·mol-1·cm-1,该法用于灌木饲料中痕量铝的测定,回收率为96.0%～106.0%,结果满意。更多还原

【Abstract】 In a hexamine-HCl buffer solution of pH 6.0～6.3, a stable complex is formed between pyrocatechol violet （PCV） and Al（Ⅲ） in the presence of CTMAB, exhibiting an absorption peak at 580nm and a negative absorption peak at 448nm. Based on this phenomenon, a method of determination of aluminum（Ⅲ） by DW-spectrophotometry using 580nm as λ₁ and 448nm as λ₂. Beer′s law is kept between ΔA(A₅₈₀-A₄₄₈) and concentration of Al（Ⅲ） in the range 0 to 6μg per 25ml of color solution. Molar absorptivity of the DW-spectrophotometric method is found to attain a value of 9.51×10⁴L·mol^-1·cm^-1 which is about 66% higher than the value of ε (5.73×10⁴L·mol^-1·cm^-1) found by the conventional spectrophotometry. In its application to the analysis of bush feed samples, consistent results were obtained in checking with the CAS photometric method, and the recoveries obtained were in the range 96.0%～106.0%.更多还原