用AL—ECR—CTMAB体系分光光度法测定土壤中的铝

Determination of Aluminum in Soils by Spectrophotometric Method Using A1-ECR-CTMAB System of Colour Reaction

本文确定了在CTMAB存在下,在pH6.7～7.4的显色反应条件下,络合物的络合比AL:ECR=1∶6,最大吸收波长为604nm,ε=1.17×10~5L·mol^(-1)·cm^(-1)·AL(Ⅲ)的浓度在3～7μg/50ml遵守比耳定律。方法简便、快速。灵敏度高,选择性好。应用于土壤、牧草中铝的测定,获得满意结果。

A spectrophotometric method was developed for determination of Aluminum in soils,based on the formation of A1-ECR-CTMAB Complex at pH 6.7—7.4 in aqueous solution. The composition ratio of Al: ECR was 1:6 when CTMAB existed. Its maximum absorbance was measured at 604nm with molar absorptivity being 1.17xl0~5L.mol^(-1).cm^(-1). Beer's law was obeyed in the Aluminum concentration range of 3～7μg/50ml. This method is simple, rapid, sensitive and selective.The proposed method was used for direct determination of Aluminum in soil and herbage samples with satisfactory results.