铁锰复合氧化物/壳聚糖珠:一种环境友好型除磷吸附剂 |
摘要点击 2651 全文点击 1102 投稿时间:2016-08-24 修订日期:2016-09-14 |
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中文关键词 铁锰复合氧化物 壳聚糖珠 磷 吸附 废水 |
英文关键词 Fe-Mn binary oxide chitosan bead phosphate adsorption wastewater |
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中文摘要 |
采用两步法制备了一种环境友好型除磷基吸附剂——铁锰复合氧化物/壳聚糖珠(FMCB),对其进行了表征,并对其磷吸附行为进行了系统研究. 表征结果表明,该吸附剂为多孔纤维结构,比表面积为248 m2·g-1,孔容为0.37 m3·g-1. 吸附实验结果表明,FMCB对磷的吸附容量远高于纯的壳聚糖颗粒,且Langmuir模型能更好地拟合FMCB对磷的吸附,最大吸附量为13.3 mg·g-1(pH 7.0);准二级动力学模型能更好地拟合FMCB对磷吸附的动力学实验数据;溶液pH对磷的吸附影响较大,随着pH的增大,磷的吸附量逐渐降低;共存的Ca2+和Mg2+对磷吸附略有促进,而共存阴离子对磷吸附具有抑制作用,影响大小顺序为:SiO32- > CO32- > SO42-≥Cl-. 吸附磷后的FMCB可用NaOH溶液进行脱附再生,并可重复使用. 在进水磷初始浓度为3 mg·L-1条件下,吸附达到穿透时(出水磷浓度达0.5 mg·L-1),可处理约800个柱体积的模拟含磷废水. |
英文摘要 |
Fe-Mn binary oxide impregnated chitosan bead (FMCB), an environmental friendly sorbent for phosphate removal, was fabricated through impregnating Fe-Mn binary oxide into chitosan matrix. The FMCB was characterized by SEM and BET surface area measurement. The adsorption behavior of phosphate on the FMCB was systemically investigated. The FMCB showed a porous and fibrous structure, with a high BET specific surface area of 248 m2·g-1 and a pore volume of 0.37 m3·g-1. It had a much higher phosphate adsorption capacity than pure chitosan bead. Langmuir model was more suitable for describing the adsorption behavior and the maximal adsorption capacity was as high as 13.3 mg·g-1 at pH 7.0.The kinetic data were well fitted by the pseudo second order model. The phosphate adsorption on FMCB was pH-dependent and decreased with increasing solution pH. Coexisting Ca2+ and Mg2+ enhanced slightly the adsorption of phosphate, while the coexisting anions hindered the phosphate adsorption in the order of SiO32- > CO32- > SO42-≥Cl-. The phosphate-loaded FMCB could be effectively regenerated using NaOH solution and repeatedly used. In column tests, about 800 bed volumes of simulated groundwater containing 3 mg·L-1 were treated before breakthrough (phosphate concentration in effluent reached 0.5 mg·L-1). |