Adsorption of congo red dye by hydrophobic o-carboxymethyl chitosan derivatives

Química Nova

Universidade do Vale do Itajaí, Itajaí, Brasil¹  Debrassi, Aline¹  Rodrigues, Clóvis Antonio¹  Largura, Maria Claudia Tonelli¹ 

关键词: adsorption;    congo red;    O-carboxymethylchitosan.;   

DOI  :  10.1590/S0100-40422011000500007

学科分类：化学（综合）

来源: Sociedade Brasileira de Quimica

【 摘 要 】

Hydrophobically modified O-carboxymethylchitosan derivatives were synthesized through a reaction with lauroyl chloride and applied for adsorption of congo red dye. The Langmuir-Freundlich isotherm model was found to be the most suitable one for the VC adsorption and maximum adsorption capacity obtained was 281.97 mg g-1 at a pH value of 7.0 for HL 1.0. The adsorption process follows the pseudo-second-order kinetics and the corresponding rate constants were obtained. The thermodynamic parameters showed that adsorption process is spontaneous (positive ∆Hº) and favorable (negative ∆Gº). The hydrophobic derivatives are able to adsorb the dye even in high pH values.

【 授权许可】

Unknown