基于凹凸棒土/聚硅酸铝铁复合吸附材料的制备及特性研究

Preparation and Characterization of Attapulgite/Polysilicate Aluminum Iron Composite Adsorption Materials

为除去地表水中溶解性有机物(DOM),本研究研发了一种新型凹凸棒土-聚硅酸铝铁复合吸附材料。首先对凹凸棒土/聚硅酸铝铁吸附材料进行活化,提高其吸附地表水中有机物的能力。结果表明,利用0.6 mol/L盐酸对其进行修饰,对地表水中UV254和TOC法测得溶解性有机物的去除效果最好,去除率分别达到46.4%和28.8%。然后利用扫描电镜、X射线衍射及红外光谱仪等手段对修饰后的材料进行表征,表征结果表明:盐酸修饰处理后的凹凸棒土表面相对原土变得疏松粗糙,改善了其比表面积,提高了其吸附性能;盐酸预处理后对凹凸棒土的晶体结构没有明显影响;凹凸棒土经预处理和负载聚硅酸铝铁改性后,碳酸盐杂质去除效果明显,整体趋于稳定,改性剂以物理吸附的形式存在于改性凹凸棒土的表面。

In order to remove dissolved organic matter(DOM)from surface water,a new type of attapulgite polysilicate aluminum iron composite adsorption material was developed in this study.Firstly,activate the attapulgite/polysilicate aluminum iron adsorption material to enhance its ability to adsorb organic matter in surface water.The results showed that using 0.6 mol/L hydrochloric acid to modify it had the best removal effect on dissolved organic matter measured by UV254 and TOC methods in surface water,with removal rates of 46.4%and 28.8%,respectively.Then,scanning electron microscopy,X-ray diffraction,and infrared spectroscopy were used to characterize the modified material.The characterization results showed that the surface of the hydrochloric acid modified attapulgite became loose and rough compared to the original soil,improving its specific surface area and adsorption performance.After hydrochloric acid pretreatment,there is no significant effect on the crystal structure of attapulgite.After pre-treatment and modification with loaded polysilicate aluminum iron,the removal effect of carbonate impurities in the modified attapulgite soil is obvious,and the overall trend is stable.The modifier exists on the surface of the modified attapulgite soil in the form of physical adsorption.