title: Activated carbon derived from carbon residue from biomass gasification and its application for dye adsorption: Kinetics, isotherms and thermodynamic studies.
abstract: In this work, activated carbon (AC) as an effective and low-cost adsorbent was successfully prepared from carbon residue (or char, one of the by-products from woody biomass gasification) via physical activation. The surface area of char was significantly increased from 172.24 to 776.46m(2)/g after steam activation at 900°C. The obtained activated carbons were then employed for the adsorption of dye (Rhodamine B) and it was found that activated carbon obtained from steam activation exhibited the highest adsorption capability, which is mainly attributed to the higher surface area and the abundance of hydroxyl (-OH) and carboxyl (-COOH) groups on the activated carbon surface. Moreover, it was also found that the adsorption capability significantly increased under the basic condition, which can be attributed to the increased electrostatic interaction between the deprotonated (negatively charged) activated carbon and dye molecules. Furthermore, the equilibrium data were fitted into different adsorption isotherms and found to fit well with Langmuir model (indicating that dye molecules form monolayer coverage on activated carbon) with a maximum monolayer adsorption capability of 189.83mg/g, whereas the adsorption kinetics followed the pseudo-second-order kinetics.
authors.affiliation: NUS Environmental Research Institute (NERI), National University of Singapore, #15-02, Create Tower, 1 Create Way, Singapore 138602, Singapore.
authors.forename: Thawatchai
authors.initials: T
authors.lastname: Maneerung
authors.affiliation: Department of Chemical & Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117585, Singapore.
authors.forename: Johan
authors.initials: J
authors.lastname: Liew
authors.affiliation: School of Mechanical Engineering, Shanghai Jiaotong University, Shanghai 200240, China.
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Dai
authors.affiliation: NUS Environmental Research Institute (NERI), National University of Singapore, #15-02, Create Tower, 1 Create Way, Singapore 138602, Singapore; Department of Chemical & Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117585, Singapore.
authors.forename: Sibudjing
authors.initials: S
authors.lastname: Kawi
authors.affiliation: Bioplas Energy (Asia Pacific) Pte Ltd, 9 Tuas South Street 15, Singapore 637077, Singapore.
authors.forename: Clive
authors.initials: C
authors.lastname: Chong
authors.affiliation: NUS Environmental Research Institute (NERI), National University of Singapore, #15-02, Create Tower, 1 Create Way, Singapore 138602, Singapore; Department of Chemical & Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117585, Singapore. Electronic address: chewch@nus.edu.sg.
authors.forename: Chi-Hwa
authors.initials: CH
authors.lastname: Wang
mesh_terms: D000327:Adsorption; D018533:Biomass; D002244:Carbon / Q000737:chemistry*; D002606:Charcoal / Q000737:chemistry*; D004396:Coloring Agents / Q000737:chemistry*; D004785:Environmental Pollutants / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D012235:Rhodamines / Q000737:chemistry*; D055672:Static Electricity; D013696:Temperature; D013816:Thermodynamics; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis
chemical_list: D004396:Coloring Agents; D004785:Environmental Pollutants; D012235:Rhodamines; D014874:Water Pollutants, Chemical; D002606:Charcoal; D002244:Carbon; C029773:rhodamine B
keywords: Activated carbon; Adsorption; Char; Rhodamine B; Waste utilization