Synthesis of a novel water-soluble chitosan derivative for flocculated decolorization.
To increase the water solubility and cationic charges at pH 7, cationic moieties were introduced onto both the C(6)-OH and C(2)-NH(2) groups in the chitosan (CTS) matrix by graft modification. The chemical structure of the obtained copolymer was demonstrated by characterizations of FT-IR, (13)C NMR, WXRD, SEM. Its excellent decolorization properties as a novel flocculant were evaluated with the C.I. Reactive Orange 5 (RO 5) and C.I. Reactive Blue 19 (RB 19) solutions using a jar test method. Both the nature of the anionic dyes and the pH of the initial dye solutions had effects on the decolorization properties. Charge neutralization played a dominant role for the color removal at pH 4, while polymer bridging contributed mainly to the color removal at pH 7. For the given flocculant/dye solutions, added salt was not in favor of the flocculated decolorization. At 25 °C, the flocculant needed for the highest color removal at pH 4 was 60 wt% of the dye (RO 5 or RB 19), but that at pH 7 were 100 wt% of RB 19 and 120 wt% of RO 5, respectively.
School of Textiles & Clothing, Key Laboratory of Eco-Textile, Ministry of Education, Jiangnan University, Wuxi 214122, PR China. jiangx@jiangnan.edu.cn
Xue
X
Jiang
Ke
K
Cai
Jing
J
Zhang
Yan
Y
Shen
Shugen
S
Wang
Xiuzhi
X
Tian
D048271:Chitosan / Q000138:chemical synthesis*; D003116:Color; D005427:Flocculation; D009682:Magnetic Resonance Spectroscopy; D008855:Microscopy, Electron, Scanning; D012995:Solubility; D017550:Spectroscopy, Fourier Transform Infrared; D014867:Water; D014961:X-Ray Diffraction
D014867:Water; D048271:Chitosan