title: Modification of granular activated carbon surface by chitosan coating for geosmin removal: sorption performances.
abstract: This study presents the results of the sorption performances for geosmin removal by sorption onto granular activated carbons (GAC) manufactured from different raw materials of coconut shell and bituminous coal. The surface of GAC was modified by chitosan coating. The 90% deacetylated chitosan flakes were used for coating on GAC with the GAC: chitosan ratio of 5:1. The surface of GAC was characterised by scanning electron microscope (SEM) analysis, Fourier transform infrared spectroscopy and measurement of the pH solution of GAC samples. The sorption of geosmin onto the chitosan for both uncoated and coated GACs could be described by the Freundlich adsorption model. Data revealed that the sequence of Freundlich constant (K(F)) was chitosan coated bitominous coal (CB) > uncoated bituminous coal (UB) > chitos approximately equal to an coated coconut shell (CC) approximately equal to uncoated coconut shell (UC). The bituminous coal based GAC with chitosan coating had a maximum capacity of 23.57 microg/g which was approximately two-fold of uncoated bituminous coal based GAC. Two simplified kinetic models, pseudo-first order and pseudo-second order, were tested to investigate the sorption mechanisms. It was found that the intraparticle diffusion was a rate controlling step for the sorption and followed the pseudo-second order equation.
authors.affiliation: Division of Environmental Technology, School of Energy and Materials, King Mongkut's University of Technology, Thonburi Pracha-uthit Road, Bangmod, Bangkok, 10140, Thailand. soydoa.vin@kmutt.ac.th
authors.forename: S
authors.initials: S
authors.lastname: Vinitnantharat
authors.forename: W
authors.initials: W
authors.lastname: Rattanasirisophon
authors.forename: Y
authors.initials: Y
authors.lastname: Ishibashi
mesh_terms: D000327:Adsorption; D002244:Carbon / Q000737:chemistry*; D002623:Chemistry Techniques, Analytical / Q000379:methods*; D048271:Chitosan / Q000032:analysis / Q000737:chemistry*; D004784:Environmental Monitoring / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008855:Microscopy, Electron, Scanning; D009284:Naphthols / Q000032:analysis*; D009812:Odorants / Q000032:analysis*; D017550:Spectroscopy, Fourier Transform Infrared; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000032:analysis; D018508:Water Purification / Q000379:methods*
chemical_list: D009284:Naphthols; D014874:Water Pollutants, Chemical; D002244:Carbon; D048271:Chitosan; C001278:geosmin