Preparation and characterization of β-FeOOH-coated sand and its adsorption of Cr（VI） from aqueous solutions

作     者：Chunhua XU Dandan CHENG Baoyu GAO Zhilei YIN Qinyan YUE Xian ZHAO 

作者机构：Shandong Key Laboratory of Water Pollution Control and Resource ReuseSchool of Environmental Science and EngineeringShandong UniversityJinan 250100China State Key Laboratory of Crystal MaterialsShandong UniversityJinan 250100China School of Chemistry and Chemical EngineeringShandong UniversityJinan 250100China 

出 版 物：《Frontiers of Environmental Science & Engineering》 (环境科学与工程前沿（英文）)

年 卷 期：2012年第6卷第4期

页      面：455-462页

核心收录：

学科分类：0830[工学-环境科学与工程（可授工学、理学、农学学位）] 083001[工学-环境科学] 07[理学] 070304[理学-物理化学(含∶化学物理)] 08[工学] 0703[理学-化学] 

基　　金：the Jinan Science and Technology Bureau the Shandong Postdoctoral Sustentation Fund support by the Independent Innovation Foundation of Shandong University 

主　　题：β-FeOOH-coated sand Cr（VI） adsorption isotherm kinetics 

摘      要：Batch adsorption experiments were conducted to explore the adsorption of Cr（VI） in aqueous solutions by fl-FeOOH-coated sand. We investigated the key factors which affected the adsorption process such as adsorbent dosage, initial pH, initial Cr（VI） ion concentration, contact time and temperature. The uptake of Cr（VI） was very rapid and 44.3%, 51.6%, 58.9% of the adsorption happened during the first 180minutes at 293K, 303K and 313K, respectively. The pseudo-second-order rate equation successfully described the adsorption kinetics. To study the adsorption isotherm, two equilibrium models, the Langmuir and Freundlich isotherms, were adopted. At 293K, 303K and 313K, the adsorption capacities obtained from the Langmuir isotherm were 0.060, 0.070 and 0.076 mg Cr（VI） per gram of the adsorbent, respectively. Thermodynamic parameters such as the change of energy, enthalpy and entropy were calculated using the equilibrium constants. The negative value of AGO and the positive value of △H^0 showed that the adsorption of Cr（VI） in aqueous solutions by β-FeOOH-coated sand was spontaneous, endothermic and occurred by physisorption.