CL-N235树脂富集-分光光度法测定粉煤灰中痕量锗

Determination of trace germanium in fine coal ash by spectrophotometry after concentration with CL-N235 resin

探讨了2-羟基-3-甲氧基苯基荧光酮（HMPF）与锗（IV）的显色反应。在pH 2.0的盐酸和酒石酸介质中,在OP存在下,HMPF与锗反应生成摩尔比为2∶1的稳定络合物,该络合物可用CL-N235树脂萃取富集,然后用光度法可测定树脂相中的锗,由此建立了测定痕量锗（IV）的新方法。吸附络合物树脂相的最大吸收波长为505 nm,表观摩尔吸光系数为1.56×105L.mol-1·cm-1。锗的质量浓度在0~480μg/L范围内符合比尔定律。经CL-N235树脂萃取富集后,锗的测定灵敏度可提高数倍,大多数常见离子不干扰测定。方法应用于粉煤灰中锗的测定,结果与苯芴酮分光光度法相符,实际样品分析结果的相对标准偏差小于4%,加标回收率为97%~102%。

The coloring reaction between 2-hydroxy-3-methoxyphenylfluorone（HMPF） and germanium was studied.In hydrochloric acid and tartaric acid medium at pH 2.0,HMPF could react with germanium to form a stable complex（molar ratio of 2∶1） in the presence of OP.The complex could be extracted and enriched by CL-N235 resin.Then,the germanium in resin phase could be determined by spectrophotometry.Consequently,a new determination method of trace germanium  was established.The maximum absorption wavelengh of adsorbed complex in resin phase was 505 nm.The apparent molar absorptivity was 1.56×105 L·mol-1·cm-1.Beer＇s law was obeyed for germanium  in mass concentration of 0-480 μg/L.After extraction and enrichment with CL-N235 resin,the determination sensitivity of germanium  was improved by several times.Moreover,most common ions did not interfere with the determination.The proposed method was applied to the determination of germanium in fine coal ash,and the results were consistent with those found by benzfluorenone spectrophotometry method.The relative standard deviations（RSD） of analytical results of actual sample were smaller than 4 %,and the recoveries of standard addition were 97 %-102 %.