改性绿茶对汞的吸附作用

Adsorption of Mercury by Modified Green Tea

关键词:  改性绿茶  汞  吸附

Key words:  modified green tea  mercury  adsorption

摘要:

采用原子吸收光谱法研究有机汞和无机汞的吸附作用。改性绿茶的用量为25mg、在pH值=7的溶液中搅拌6min,无机汞的吸附率达95%,有机汞的吸附率不大于5%;同等量的改性绿茶在pH值=1的溶液中搅拌9min,有机汞的吸附率可达到90%以上。10次重复分离测定0.1μg·ml^-1汞溶液,测得无机汞、有机汞的检出限分别为0.06μg·L^-1和0.08μg·L^-1,相对标准偏差为8.6%和5.8%,回收率为92.5%~105.3%和93.8%~106.6%。实验还表明,在盐酸浓度分别为2.0mol·L^-1、6min和4.0mol·L^-1、11min,共存KCl的量为100mg,可定量解吸无机汞和有机汞。

Abstract:

The conditions for the separation of inorganic Hg and organic Hg with modified green tea were studied by cold vapour atomic adsorption spectrometry. The 25 mg modified green tea is used. 95% of inorganic Hg and no more than 5% organic Hg were adsorbed by the modified green tea at the solution of pH value=7 for 6 min. 90% of organic Hg is adsorbed by the modified green tea at the solution of pH value=1 for 9 min. The limited detection is 0.06 μg·L^-1 to 0.08 μg·L^-1 for inorganic Hg and organic Hg respectively with relative standard deviation of 8.65% and 5.8% and recovery of 92.5%~105.3% and 93.8%~106.6% at the 10 repeats of detections of 0.1 μg·ml^-1 Hg solution. The inorganic Hg and organic Hg can be quantitatively desorbed at HCl of 2.0 mol·L^-1 for 6 min and 2.0 mol·L^-1 for 11 min,with 100 mg KCl.