Abstract
The efficiency of Fe2O3, Al2O3 and TiO2 nanoparticles-loaded activated carbon (AC) for the adsorption of phenol from waters, was investigated. The raw and doped ACs were characterized by using Scanning Electron Microscopy, Energy Dispersive X-ray Spectroscopy, Thermogravimetric analysis and Brunauer-Emmett-Teller surface analysis. Batch adsorption experiments were performed to evaluate the effects of solution pH, agitation speed, contact time, adsorbent dosage and ionic strength on the phenol removal efficiency. Activated carbon impregnated with Fe2O3, Al2O3 and TiO2 showed higher adsorption capacity compared to raw AC. The maximum removal of phenol was achieved by iron oxide, aluminum Oxide and titanium oxide doped AC under the optimum conditions of 200 mg dosage, at pH 7, 150 rpm agitation speed, 2 ppm initial phenol concentration and contact time of 2 h. While for raw AC, the maximum removal was achieved for an adsorbent dosage of 300 mg under the same treatment conditions. The Langmuir isotherm model best fitted the data of the adsorption of phenol using AC, AC-TiO2, AC-Fe2O3 and AC-Al2O3, with correlation coefficient of 0.971, 0.96, 0.976 and 0.972. Surface characterization of both the impregnated AC showed an improvement in its surface area of the doped AC. The adsorption capacities, as determined by the Langmuir isotherm model were 1.5106, 3.1530, 3.2875 and 3.5461 mg/g for raw AC, AC-TiO2, AC-Fe2O3 and AC-Al2O3. (C) 2015 Elsevier B.V. All rights reserved.