制备方法对铁钛复合氧化物磷吸附性能的影响:共沉淀法与机械物理混合法  

Effect of Preparation Methods on Phosphate Adsorption by Iron-Titanium Binary Oxide:Coprecipitation and Physical Mixing

作　　者：仲艳 王建燕[1,2] 陈静 张高生[3] ZHONG Yan;WANG Jiang-yan;CHEN Jing;ZHANG Gao-sheng(Key Laboratory of Coastal Environmental Proeesses and Eeological Remediation, Research Center for Coastal Environment Engineering and Technology of Shandong Provinee, Yantai Institute of Coastal Zone Research, Chinese Academy of Seiences, Yantai 264003, China;University of Chinese Academy of Sciences, Beijing 100049, China;Key Laboratory of Water Safety and Proteetion in Pearl River Delta, Ministry of Edueation, Guangzhou University, Guangzhou 510006, China)

机构地区：[1]中国科学院烟台海岸带研究所中国科学院海岸带环境过程与生态修复重点实验室山东省海岸带环境工程技术研究中心,烟台264003 [2]中国科学院大学,北京100049 [3]广州大学珠江三角洲水质安全与保护协同创新中心暨省部共建重点实验室,广州510006

出　　处：《环境科学》2018年第7期3230-3239,共10页Environmental Science

基　　金：国家自然科学基金项目(51478457);中国科学院烟台海岸带研究所自主部署项目(YICY755021012)

摘　　要：为了研究制备方法对金属复合氧化物表面性质与吸附性能的影响,本文分别采用共沉淀法与机械物理混合法制备了铁钛复合氧化物CFe-Ti与MFe-Ti.采用SEM、BET、XRD与FTIR等表征技术,研究了两种铁钛复合氧化物CFe-Ti与MFe-Ti的形貌结构、比表面积、表面羟基浓度等表面特性;通过批式吸附实验,考察了其磷吸附性能.结果表明,与纯的氧化物Fe OOH及TiO_2相比,共沉淀法制备的CFe-Ti纳米颗粒更疏松,孔结构更发达,表面羟基浓度更高,CFe-Ti的最大磷吸附容量达40.6mg·g^(-1),高于纯Fe OOH(27.2 mg·g^(-1))与TiO_2(16.7 mg·g^(-1)),分别为其1.5倍和2.4倍,展示了显著的协同效应.而MFe-Ti的形貌结构和表面性质与Fe OOH及TiO_2相比变化不大,其磷最大吸附容量为22.7 mg·g^(-1),不仅明显低于CFe-Ti,且低于纯Fe OOH,表明未产生协同效应.研究也表明,磷在CFe-Ti与MFe-Ti表面的吸附性质未发生变化,均通过形成内层表面络合物而发生了化学吸附.因此,金属复合氧化物的表面性质和吸附性能与其制备方法密切相关,与机械物理混合法相比,共沉淀法是一种更为简单经济制备高效能铁钛复合氧化物磷吸附剂的方法.To investigate the effect of preparation methods on surface characteristics and adsorption properties of the formed metal composite oxides,two kinds of iron-titanium binary oxides were synthesized by a coprecipitation method or a physical mixing method and were denoted asCFe-Ti andMFe-Ti,respectively. The preparedCFe-Ti andMFe-Ti were systematically characterized using SEM,XRD,BET,and FTIR techniques. Their phosphate adsorption behaviors were also studied via batch adsorption experiments. Compared with pure Fe OOH and TiO2,CFe-Ti exhibited a looser nanostructure with more pore and surface hydroxyls. Moreover,theCFe-Ti had a high maximal phosphorus adsorption capacity of 40. 6 mg·g^-1,which is about 1. 5 times and 2. 4 times as high as that of pure Fe OOH（ 27. 2 mg·g^-1） and TiO2（ 16. 7 mg·g^-1）,respectively. This suggests that an obvious synergistic effect is present in theCFe-Ti system. However,the morphology and structure ofMFe-Ti were not significantly different from those of pure Fe OOH and TiO2. The maximal adsorption capacity ofMFe-Ti was 22. 7 mg·g^-1,which is obviously lower than that ofCFe-Ti and even lower than that of pure Fe OOH. Evidently,there is no synergistic effect in theMFe-Ti system. In addition,phosphate adsorption mechanisms at the surface of CFe-Ti andMFe-Ti were the same as those of their component oxides,and chemical adsorption occurred at the surface of the oxides through the formation of inner-sphere complexes. Therefore,the surface characteristics and adsorption properties of the metal composite oxides were closely related to their preparation methods. The coprecipitation method was a simpler and more economical way than the physical mixing method to fabricate a highly effective iron-titanium binary oxide for phosphate adsorption.

关 键 词：铁钛复合氧化物 共沉淀 机械物理混合 磷 吸附 

分 类 号：X703.1[环境科学与工程—环境工程] X131.2