【摘要】 研究了1,2-二羟基蒽醌-3-磺酸钠与钒(Ⅴ)的显色反应,建立了测定钒的光度分析新方法。在pH 4.0的醋酸-醋酸钠缓冲溶液中,在溴化十六烷基三甲基铵(CTMAB)存在下,1,2-二羟基蒽醌-3-磺酸钠与钒(Ⅴ)反应生成摩尔比为2∶1稳定络合物,该络合物可用阳离子交换树脂固相萃取柱富集,吸附柱上富集的络合物用乙醇洗脱后用分光光度法测定。分离后的测定液中,络合物最大吸收波长为420 nm,表现摩尔吸光系数ε=1.16×105L.mol-1.cm-1,钒量在0~0.4μg/mL内符合比尔定律,相关系数r=0.998 9,对30余种共存离子进行试验,大多数常见离子不干扰测定。方法用于合金、矿石、粉煤灰中钒的分析,相对标准偏差小于3%,加标回收率为96%~105%。更多还原

【Abstract】 A new spectrophotometric method was developed for the determination of trace vanadium based on the rapid reaction of vanadium(Ⅴ) with 1,2-dihydroxyanthraquinone-3-sulfonic acid sodium.In the presence of CTMAB,1,2-dihydroxyanthraquinone-3-sulfonic acid sodium reacts with vanadium(Ⅴ) to form a stable complex with molar ratio of 2∶1 in HAc-NaAc buffer solution(pH 4.0).The complex was extracted by cation exchange resin cartridge and was eluted with ethanol,then be determined by spectrophotometry.The apparent molar absorptivity ε is 1.16×105 L·mol-1·cm-1 at 420 nm.Beer’s law is obeyed in the range of 0-0.4 μg/mL for V(Ⅴ) and r=0.998 9.More than 30 coexistent ions didn’t disturb the determination.This method has been applied to the determination of vanadium(Ⅴ) in alloy,rock and fly ash samples with the RSD less than 3% and the recovery of 96%-105%.更多还原