利用凝胶层析分离测定胶体态铝和溶解态铝的研究

利用凝胶层析柱分别对高浓度(5.4g·L-1)和低浓度(0.27mg·L-1)的聚合氯化铝溶液和氯化铝溶液进行了层析分离,测定了洗脱流出液的电导率和pH值,并采用Al-Ferron逐时络合比色分析了洗脱流出液中的铝形态分布.结果表明,高浓度和低浓度铝水样中的胶体态铝和溶解态铝浓度均可采用凝胶层析法进行分离测定.利用凝胶层析装置对2.5mL铝水样以1mL·min-1的速度进行洗脱,40～60mL间的洗脱流出液即为胶体态铝,剩余部分为溶解态铝.

Study on the separation and determination of colloidal aluminum and soluble aluminum by gel chromatography

The polyaluminum chloride (PAC) solution and aluminum chloride solution with high (5.4g·L^-1) and low (0.27mg·L^-1) Al concentrations were chromatographed by gel-filtration column, respectively. The conductivity and pH value of the eluted fractions were measured and the aluminium species distribution of the eluted fractions was also analyzed by Ferron assay. The experimental results show that the separation and determination of colloidal aluminum and soluble aluminum in the water samples with high or low Al content can be achieved by gel chromatography. Under the condition that 2.5mL of the studied sample is eluted at a rate of 1 mL·min^-1 with the gel-filtration device, the eluted fraction from 40mL to 60mL corresponds to the colloidal aluminum and the rest part corresponds to the soluble aluminum. The concentrations of the colloidal aluminum and the soluble aluminum can be achieved by measurement with inductively coupled plasma (ICP) spectrometer plus further conversion.