黄河沉积物对芳烃类有机物的吸附特性研究

Adsorption of Aromatic Compounds on Sediments Collected from the Yellow River

以黄河包头段上游相对清洁河段的沉积物为吸附剂,分别以苯酚、苯胺、氯苯等3种代表性芳烃类有机污染物为吸附质,开展了芳烃类有机物的吸附特性及相关影响因素的研究。结果表明,苯酚、苯胺、氯苯在黄河沉积物上的吸附等温线属非线性,其吸附特性受吸附剂浓度和种类的影响;苯酚和苯胺的吸附行为受pH值影响显著;溶液的离子强度、沉积物中有机质含量、环境温度等均对3种有机污染物的吸附量产生较大影响。

The contents of organic pollutants in the Yellow River, which may have ecological risks and do harm to human health further through food chains, are increasing gradually. Therefore, more attention given to organic pollutant is of essence. Having taken the sediments from the clear reach in Baotou Section ofthe Yellow River as the adsorbent, and the solutions containing phenol, anilineand chlorobenzene as the adsorbates, we did a test to show adsorption and affecting factors on aromatic compounds. According to the results obtained from the experiments, the adsorption isotherms of each adsorbate were nonlinear, and concentration and types of adsorbent influenced their characterization of adsorption,respectively. Elevating adsorbent concentration, the adsorption capacity decreased and the net amount of adsorption generally increased and compared with the surface sediment, the adsorption capacity on the suspended particulates is clearly higher at the same condition. In addition, the adsorbability of each adsorbatewas influenced by pH, ionic strength, temperature and organic contents in sediments and so on. The adsorption of phenol and aniline was influenced apparently by pH ranging from 2 to 12, while was not for the adsorption of chlorobenzene. High ionic strength was not propitious to the adsorption of phenol and chlorobenzene, neither was aniline; while increased organic content was not propitious to the adsorption of phenol but just reverse for both aniline and chlorobenzene; andelevated temperature make against all three adsorption on the surface sediment indicating the adsorption is exothermic process.