title: Chromium (III) removal by weak acid exchanger Amberlite IRC-50 (Na).
abstract: Chromium (III) sorption on a weakly macroporous cation exchanger Amberlite IRC-50 (Na) is studied as a function of time and temperature. The rate constant values for chromium (III) sorption are calculated both for film and particle diffusion processes. The temperature is found to have a positive effect on both the diffusional processes. The high values of energy of activation confirm the particle diffusional nature of the process. The pH changes in the system show a competition between the Cr(OH)(2+) and H(+) ions for the exchange sites of the adsorbent. Equilibrium data are explained with the help of Langmuir equation. Various thermodynamic parameters (DeltaH degrees , DeltaS degrees and DeltaG degrees) from chromium (III) exchange on the resin are calculated.
authors.affiliation: National Centre of Excellence in Physical Chemistry, University of Peshawar, Peshawar, Pakistan. smustafa49@yahoo.com
authors.forename: S
authors.initials: S
authors.lastname: Mustafa
authors.forename: K H
authors.initials: KH
authors.lastname: Shah
authors.forename: A
authors.initials: A
authors.lastname: Naeem
authors.forename: M
authors.initials: M
authors.lastname: Waseem
authors.forename: M
authors.initials: M
authors.lastname: Tahir
mesh_terms: D000465:Algorithms; D002411:Cation Exchange Resins / Q000737:chemistry*; D002857:Chromium / Q000737:chemistry* / Q000302:isolation & purification; D004058:Diffusion; D007700:Kinetics; D012117:Resins, Synthetic / Q000737:chemistry*; D012964:Sodium / Q000737:chemistry; D013816:Thermodynamics
chemical_list: D002411:Cation Exchange Resins; D012117:Resins, Synthetic; D002857:Chromium; C024946:Amberlite IRC50; D012964:Sodium