论文部分内容阅读
于pH 6.6的乙酸盐缓冲溶液中,五价钒离子与焦性没食子酸反应生成有色络合物。此络合物可吸附于717强碱性阴离子交换树脂上,并在树脂相上于600 nm波长处,以按试样分析相同步骤制备的树脂空白作参比测得其吸光度。对显色反应、呈色络合物在树脂上的吸附、共存离子的干扰及其消除等条件作了研究和优化。在树脂相光度测定的条件下,钒(Ⅴ)浓度在0~37μg/25 mL间遵守比耳定律,摩尔吸光系数达5.57×104L.mol-1.cm-1,约为水相测定的10倍,应用于测定钢中钒,大量铁(Ⅲ)须预先用溶剂萃取予以分离,显色时再加CyDTA作掩蔽剂,测定结果的RSD(n=5)值小于3%,回收率在98.6%~102.6%之间。
In pH 6.6 acetate buffer solution, pentavalent vanadium ions react with pyrogallol to produce colored complexes. The complex can be adsorbed on 717 strong basic anion exchange resin and the absorbance is measured on the resin phase at a wavelength of 600 nm with reference to the resin blank prepared according to the same procedure as the sample analysis. The conditions of color reaction, adsorption of colorants on resin, interference of coexisting ions and their elimination were studied and optimized. Under the condition of resin phase photometry, the Beer’s law was obeyed at the concentration of vanadium (V) between 0 ~ 37μg / 25mL and the molar absorptivity reached 5.57 × 104L.mol-1.cm-1, which was about 10 Times, used in the determination of vanadium in steel. A large amount of iron (Ⅲ) should be separated by solvent extraction in advance. CyDTA was used as masking agent when color was developed. The RSD (n = 5) value was less than 3% and the recovery was 98.6 % ~ 102.6% between.