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 m^2·g^(-1),孔容为0.37 m^3·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Ca^(2+)和Mg^(2+)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:SiO_3^(2-)>CO_3^(2-)>SO_4^(2-)≥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.
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 m^2·g^-1and a pore volume of 0. 37 m^3·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^-1at 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 Ca^2＋and Mg^2＋enhanced slightly the adsorption of phosphate,while the coexisting anions hindered the phosphate adsorption in the order of SiO3^（2-）CO3^（2-） SO4^（2-）≥ Cl^-. The phosphate-loaded FMCB could be effectively regenerated using Na OH solution and repeatedly used. In column tests,about 800 bed volumes of simulated groundwater containing 3 mg·L^-1were treated before breakthrough（ phosphate concentration in effluent reached 0. 5 mg·L^-1）.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2016年第12期4882-4890,共9页
Environmental Science
基金
国家自然科学基金项目(51478457)
关键词
铁锰复合氧化物
壳聚糖珠
磷
吸附
废水
Fe-Mn binary oxide
chitosan bead
phosphate
adsorption
wastewater
