title: Elimination of reactive blue 4 from aqueous solutions using 3-aminopropyl triethoxysilane modified chitosan beads.
abstract: The adsorption behavior of chitosan (CS) beads modified with 3-aminopropyl triethoxysilane (APTES) for the removal of reactive blue 4 (RB4) in batch studies has been investigated. The effects of modification conditions, such as the APTES concentration, temperature and reaction time on RB4 removal, were studied. The adsorbent prepared at a concentration of 2 wt% APTES for 8h at 50 °C was the most effective one for RB4 adsorption. The adsorption capacity of modified CS beads (433.77 mg/g) was 1.37 times higher than that of unmodified CS beads (317.23 mg/g). The isotherm data are adequately described by a Freundlich model, and the kinetic study revealed that the pseudo-second-order rate model was in better agreement with the experimental data. The negative values of the thermodynamic parameters, including ΔG° (-2.28 and -4.70 kJ/mol at 30 ± 2 °C), ΔH° (-172.18 and -43.82 kJ/mol) and ΔS° (-560.71 and -129.08 J/mol K) for CS beads and APTES modified beads, respectively, suggest that RB4 adsorption is a spontaneous and exothermic process.
authors.affiliation: School of Industrial Technology, Universiti Sains Malaysia, Gelugor 11800, Penang, Malaysia.
authors.forename: Mohammadtaghi
authors.initials: M
authors.lastname: Vakili
authors.affiliation: School of Industrial Technology, Universiti Sains Malaysia, Gelugor 11800, Penang, Malaysia. Electronic address: mohd_rafatullah@yahoo.co.in.
authors.forename: Mohd
authors.initials: M
authors.lastname: Rafatullah
authors.affiliation: School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, 46150 Bandar Sunway, Selangor, Malaysia.
authors.forename: Babak
authors.initials: B
authors.lastname: Salamatinia
authors.affiliation: School of Industrial Technology, Universiti Sains Malaysia, Gelugor 11800, Penang, Malaysia.
authors.forename: Mahamad Hakimi
authors.initials: MH
authors.lastname: Ibrahim
authors.affiliation: School of Chemical Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang, Malaysia.
authors.forename: Ahmad Zuhairi
authors.initials: AZ
authors.lastname: Abdullah
mesh_terms: D000327:Adsorption; D048271:Chitosan / Q000031:analogs & derivatives*; D004396:Coloring Agents / Q000302:isolation & purification*; D007700:Kinetics; D011437:Propylamines / Q000737:chemistry*; D012821:Silanes / Q000737:chemistry*; D013816:Thermodynamics; D014227:Triazines / Q000302:isolation & purification*; D014867:Water / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods
chemical_list: D004396:Coloring Agents; D011437:Propylamines; D012821:Silanes; D014227:Triazines; D014874:Water Pollutants, Chemical; D014867:Water; C036598:procion blue MX-R; D048271:Chitosan; C477625:amino-propyl-triethoxysilane
keywords: 3-Aminopropyl triethoxysilane; Adsorption; Chitosan beads; Dye removal; Reactive blue 4