钴掺杂叶片状沸石咪唑酯骨架结构材料实现磷酸盐快速去除

Co-doped zeolitic imidazolate framework-L for more rapid phosphate removal

为了减小水体富营养化的危害,提高吸附法除磷的效率,本文研究钴掺杂对于锌基叶片状沸石咪唑盐(Zn-ZIF-L)磷酸盐吸附能力的提升.本文采用间歇式吸附试验研究各个影响因素对于吸附的影响,采用XRD、XPS、FT-IR等研究材料的表面微观结构以推测可能的吸附机理.发现当Zn和Co的初始摩尔比为9.5:0.5时,其吸附性能最好.掺杂后,在10min内吸附量增加55%,最大吸附量达到85.68mg/g,在不同温度、浓度、当pH值为4~8时、在不同阴离子以及腐殖酸环境下保持着较好的吸附性能.当初始浓度为10mg/L时,可吸附去除97%以上的磷,吸附剂在0.1mol/L的Cl^(-)或NO_(3)^(-)中仍能保持93%以上的吸附量.其中,P-OH与Zn-OH/Co-OH之间的化学键、静电相互作用和氢键相互作用在磷酸盐吸附中起主导作用.Co(0.5)-Zn-ZIF-L经过4次循环后仍能保持较高的吸附量.结果表明,Co(0.5)-Zn-ZIF-L能作为一种有效的吸附剂去除水体中的磷酸盐.

In order to reduce the harm of water eutrophication and improve the efficiency of phosphorus removal by adsorption method,this paper studied the effect of cobalt doping on the phosphate adsorption capacity of Zinc-based leaf zeolitic imidazolate framework-L(Zn-ZIF-L).In this paper,intermittent adsorption tests were used to study the influence of various influencing factors on the adsorption.XRD,XPS,FT-IR and other methods were used to study the surface microstructure of the materials to speculate the possible adsorption mechanism.It was found that the adsorption performance of Zn was the best when the initial molar ratio of Zn to Co was 9.5:0.5.After doping,the adsorption capacity increased by 55%within 10min,the maximum adsorption capacity could reach 85.68mg/g,and the adsorption performance was maintained under different temperature,concentration,p H value of 4~8,different anions and humic acid environments.When the initial concentration was 10mg/L,more than 97%of phosphorus could be adsorbed.More than 93%of phosphorus could be retained in 0.1mol/L Cl^(-)or NO_(3)^(-).Additionally,the chemical bonding between P-OH and Zn-OH/Co-OH,electrostatic interaction,and hydrogen bond interaction played a leading role in phosphate adsorption.Moreover,Co(0.5)-Zn-ZIF-L could keep a high adsorption capacity after four cycles.These findings suggest that Co(0.5)-Zn-ZIF-L can effectively remove phosphate from water.