水中微量镉的浓集和测定

PRE-CONCENTRATION AND DETERMINATION OF MICRO AMOUNTS OF Cd IN WATER

本文研究了碱式碳酸镁作为一种新的无机吸附共沉淀剂对水中镉的富集和测定.实验发现,它能有效地富集水中微量镉,1g碱式碳酸镁在500mll溶液中(pH8—9,镉浓度O—200μg/l)搅拌吸附20mim时,镉的吸附率可达94％以上.用分光光度法满意地实现了对河水及自来水中微量镉的测定.结果表明:镉的加入回收率≥94％,测定的相对标准偏差≤4％,共存杂质离子在一定范围内不影响测定.

Pre-concentration for Cd in water basic magnesium carbonate, as a new inorganic adsorbent-coprecipitant, has been studied. It was found that basic magnesium carbonate can efficiently concentrate micro amounts of Cd in water. Jg basic magnesium carbonate was used for the adsorbent in 500ml solution (pH8-9,0-200μg/l),the adsoptivity is greater that 94% under 20min stirring. Determination of micro amounts of Cd in river-water and tap water has been achieved satisfactorily by using spectrophotometry. Recovery of Cd is greater that 94% and relative standard deviation is equal or less than 4 % and the no interferences have been found for Cd determination in water samples.