Determination of trace germanium in fine coal ash by spectrophotometry after concentration with CL-N235 resin
DAI Cai-sheng1,2，LUO Dao-cheng*1
1. School of Chemistry and Chemical Engineering，Hunan University of Science and Technology，Xiangtan 411201，China；2. Hunan Provincal Key Laboratory of Clean Coal and Mine Environmental Protection，Xiangtan 411201，China
Abstract：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 %.
戴财胜，罗道成*. CL-N235树脂富集-分光光度法测定粉煤灰中痕量锗[J]. 冶金分析, 2011, 31(7): 72-75.
DAI Cai-sheng，LUO Dao-cheng*. Determination of trace germanium in fine coal ash by spectrophotometry after concentration with CL-N235 resin. , 2011, 31(7): 72-75.
