摘要
通过化学沉淀法制备了表面带负电的光催化材料溴氧铋(BiOBr),在BiOBr存在条件下,采用非稳态共沉淀法制备了Zn/Al物质的量比分别为2∶1和3∶1的两种Zn-Al类水滑石(HTlc)@BiOBr复合材料(Zn_(2)AlHTlc@BiOBr和Zn_(3)AlHTlc@BiOBr),且二者均带正电且有较大比表面积和总孔体积。研究了两种复合材料对甲基橙的吸附性能,探讨了Zn/Al物质的量比对吸附性能的影响。结果表明,不同样品对甲基橙的吸附能力依次为:Zn_(2)AlHTlc@BiOBr>Zn_(3)Al HTlc@BiOBr>Zn_(2)Al HTlc>Zn_(3)Al HTlc>BiOBr;Zn_(2)AlHTlc@BiOBr对甲基橙的吸附等温线符合Freundlich方程,平衡吸附量随温度(298~318 K)升高而升高,吸附为自发、吸热和熵增的物理吸附过程;比表面积和总孔体积是决定吸附能力的重要因素。
A BiOBr photocatalyst was firstly prepared by chemical precipitation,and then two kinds of Zn-Al hydrotalcite compound(HTlc)@BiOBr composites with different Zn/Al molar ratio,namely Zn_(2)Al HTlc@BiOBr and Zn_(3)Al HTlc@BiOBr,were prepared by unstable coprecipitation in the presence of BiOBr.Zn-Al HTlc@BiOBr composites were positively charged and had large specific surface areas and total pore volumes.The adsorption properties of Zn-Al HTlc@BiOBr composites for methyl orange were studied,especially the effect of Zn/Al molar ratio on the adsorption was discussed in detail.The results showed that,the adsorption capacity for methyl orange was Zn_(2)Al HTlc@BiOBr>Zn_(3)Al HTlc@BiOBr>Zn_(2)Al~HTlc>Zn_(3)Al HTlc>BiOBr,the adsorption isotherms of Zn_(2)Al HTlc@BiOBr for methyl orange were consistent with Freundlich equation,and the adsorption amounts increased with the increase of temperature(298~318 K).The adsorption process was a spontaneous endothermic and entropy-increasing physical adsorption;the specific surface area and total pore volume were important factors to determine the adsorption capacity.
作者
毕浩宇
李燕
李芳芳
Bi Haoyu;Li Yan;Li Fangfang(Department of Biomedical Engineering,Changzhi Medical College,Changzhi,Shanxi 046000,China;Department of Chemistry,Changzhi University,Changzhi,Shanxi 046011,China)
出处
《化学世界》
CAS
2022年第4期193-198,共6页
Chemical World
基金
山西省自然科学基金面上(No.201701D121034)资助项目。
关键词
类水滑石
溴氧铋
复合材料
吸附
hydrotalcite-like compound
bismuth bromide
composites
adsorption
