Abstract
Sorel's cement nanoparticles prepared via sol-gel method was used for removal of methyl orange ( MO) and bromophenol blue (BPB) from their aqueous solutions. Removal efficiency considered the effects of contact time, adsorbent dosage, initial dye concentration and temperature. Adsorption data showed better fitting to Freundlich isotherm equation, while Langmuir model represented the results with lower but acceptable correlation coefficients implying surface heterogeneity. Maximum adsorption was 23.21 and 4.88 mg/g from MO and BPB, respectively. The adsorption of MO followed the pseudo-second order kinetics; whereas first order kinetics better fitted the data from BPB. Removal of both dyes proceeded endothermically with triangle H of + 10.3 and + 7.8 kJ/mol for MO and BPB, respectively. Obtained results indicate that Sorel's cement represents an efficient adsorbent for removal of MO and BPB from aqueous solution. (C) 2015 Elsevier Ltd. All rights reserved.