title: Glow discharge plasma in water: a green approach to enhancing ability of chitosan for dye removal.
abstract: There is a need to explore effective and green approaches to enhancing the ability to use chitosan for contaminant removal for practical implementation of this technology. In the present study, glow discharge plasma (GDP), which has thus far been studied for degradation of contaminants, was used for the first time to pre-treat chitosan for dye removal in aqueous solution. The results show that the GDP treatment changed the morphology and crystallinity of chitosan particles, and the number of -CH(2) and -CH(3) groups in the chitosan samples increased. Various pretreatment parameters, including discharge current and time, played significant roles in the chitosan modification. It is observed that dye uptake in GDP-modified chitosan was faster than adsorption in untreated chitosan. The maximum adsorption by chitosan followed the order of untreated chitosan<modified chitosan (GDP current: 50 mA)<modified chitosan (GDP current: 120 mA), implying that the chitosan modified by GDP had a higher maximum adsorption capacity in comparison with the untreated chitosan. A possible mechanism is proposed. These results show that GDP may be an attractive pretreatment technology for environmental adsorption materials.
authors.affiliation: Institute of Environmental Science, Zhejiang University, Hangzhou 310058, China. wenyuezhong@zju.edu.cn
authors.forename: Yuezhong
authors.initials: Y
authors.lastname: Wen
authors.forename: Chensi
authors.initials: C
authors.lastname: Shen
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Ni
authors.forename: Shaoping
authors.initials: S
authors.lastname: Tong
authors.forename: Feng
authors.initials: F
authors.lastname: Yu
mesh_terms: D000327:Adsorption; D001391:Azo Compounds / Q000302:isolation & purification*; D048271:Chitosan / Q000737:chemistry*; D004396:Coloring Agents / Q000302:isolation & purification*; D055664:Electrochemical Techniques / Q000295:instrumentation / Q000379:methods*; D004566:Electrodes; D055772:Green Chemistry Technology; D015394:Molecular Structure; D009282:Naphthalenesulfonates / Q000302:isolation & purification*; D010084:Oxidation-Reduction; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D018508:Water Purification / Q000295:instrumentation / Q000379:methods*
chemical_list: D001391:Azo Compounds; D004396:Coloring Agents; D009282:Naphthalenesulfonates; D014874:Water Pollutants, Chemical; C408149:brilliant crocein; D048271:Chitosan