纳米水滑石的结构表征及其对氯离子的吸附性能  

Structure and Chloride Ion Adsorption of Nanosized Hydrotalcite

作　　者：李志敏[1] 凤颀[1] 张连红[1] 梁红玉[1] 张悦 杨敏 

机构地区：[1]辽宁石油化工大学,辽宁抚顺113001 [2]中石化洛阳分公司,河南洛阳471000 [3]中油抚顺石化公司,辽宁抚顺113001

出　　处：《材料科学与工程学报》2016年第6期998-1003,共6页Journal of Materials Science and Engineering

基　　金：辽宁省自然科学基金资助项目(2013020136)

摘　　要：以天然菱镁矿为原料,采用尿素法制备纳米Mg-Zn-Al水滑石(LDH)、Zn-Mg-Al-Fe水滑石,采用XRD、SEM、N2吸附-脱附对水滑石的结构特征、晶粒尺寸进行表征,并利用水滑石的层间阴离子交换性及结构"记忆效应",来研究焙烧态水滑石(CLDH)对溶液中氯离子的吸附性能。结果表明:Zn-Mg-Al-LDH结晶度比Mg-Al-LDH、Zn-Mg-Al-Fe-LDH高,同时Zn-Mg-Al-LDH的粒径非常均匀,尺寸在20nm左右,为层片状结构,而且其晶体结构呈现花瓣状结构;在Mg-Al-CLDH中,随着n(Mg/Al)的增加,溶液中Cl^-的去除率逐渐提高,且在n(Mg/Al)=4时去除率最大,为85.96%;当n(M^(2+)/M^(3+))固定为2时,Zn-Mg-Al-CLDH对Cl^-的去除率要比Mg-Al-CLDH对Cl^-的去除率高13.25%,但Zn-Mg-Al-Fe-CLDH的去除率却比Mg-Al-CLDH低32.53%;焙烧态水滑石n(Zn/Mg/Al)=1∶1∶1时,有较大的比表面积837.183m^2/g,较大的孔容为0.496cc/g,其相应吸附能力也较大。Mg-Zn-Al and Zn-Mg-Al-Fe hydrotalcite were synthesized by the urea homogeneous precipitation method,in which natural magnesite was used as raw material.Structural features and grain size of the hydrotalcite were characterized by XRD,SEM and N2adsorption-desorption isotherm measurement.Taking into account the inter-layer anion exchange property and the structure memory effect of the hydrotalcite,chloride ion adsorption properties of CLDH in solution were researched.The results show that the crystallinity of Zn-Mg-Al-LDH system is higher than Mg-Al-LDH and Zn-Mg-Al-Fe-LDH systems.The particle size of the Zn-Mg-Al-LDH system is uniform with its lamellar structure size of about 20 nm,and the morphology of it is perfect petaloid.In Mg-Al-CLDH system,with the increase of n（Mg/Al）,the removal rate of Cl-in the solution gradually increase,and the highest removal rate is 85.96% when the n（Mg/Al）=4.When n（M（2＋）/M（3＋））was fixed to 2,the Cl-removal rate of Zn-Mg-Al-CLDH is 13.25%,higher than that of Mg-Al-CLDH,but the Cl-removal rate of Zn-Mg-Al-Fe-CLDH is 32.53%,lower than that of Mg-Al-CLDH;Specific surface area and pore volume of calcination hydrotalcite of n（Zn/Mg/Al）=1∶1∶1can reach as high as 837.183m2/g and0.496cc/g,respectively,thus having high adsorption capacity correspondingly.

关 键 词：菱镁矿 水滑石 尿素 氯离子 吸附 

分 类 号：TU375.4[建筑科学—结构工程]