title: Adsorption of chromium from aqueous solution by activated alumina and activated charcoal.
abstract: Cr(VI) is considered to be potentially carcinogenic to humans. Removal of Cr(VI) ions from aqueous solution under different conditions was investigated using activated alumina (AA) and activated charcoal (AC) as adsorbents. Batch mode experiments were conducted to study the effects of adsorbent dose, contact time, pH, temperature and initial concentration of Cr(VI). Results showed that the adsorption of Cr(VI) depended significantly on pH and temperature. Equilibrium studies showed that Cr(VI) had a high affinity for AA at pH 4 and AC at pH 2. For AA, maximum adsorption was found at 25 degrees C, indicating exothermic adsorption, while for AC, maximum adsorption was at 40 degrees C. Freundlich and Langmuir adsorption isotherms were also applied and they showed good fits to the experimental data. The results suggest that both AA and AC could be used as effective adsorbents for the removal of Cr(VI) ions.
authors.affiliation: Department of Energy and Environmental Science, Chaudhary Devi Lal University, Sirsa, Haryana 125 055, India. sumanmor@yahoo.com
authors.forename: Suman
authors.initials: S
authors.lastname: Mor
authors.forename: Khaiwal
authors.initials: K
authors.lastname: Ravindra
authors.forename: N R
authors.initials: NR
authors.lastname: Bishnoi
mesh_terms: D000327:Adsorption; D000537:Aluminum Oxide / Q000737:chemistry*; D002606:Charcoal / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D012996:Solutions; D013056:Spectrophotometry, Ultraviolet; D013816:Thermodynamics; D014867:Water
chemical_list: D012996:Solutions; D014867:Water; D002606:Charcoal; D000537:Aluminum Oxide