Chitosan-supported palladium catalyst. IV. Influence of temperature on nitrophenol degradation and thermodynamic parameters

JOURNAL OF ENVIRONMENTAL MANAGEMENT

卷:71

Article

Guibal, E ; Vincent, T

关键词: nitrophenol;    chitosan;    palladium;    catalysis;    hydrogen transfer;    sodium formate;    kinetics;    conversion yield;    activation energy;   

DOI  :  10.1016/j.jenvman.2004.01.003

来源: Elsevier

【 摘 要 】

Glutaraldehyde cross-linked chitosan was loaded with palladium and then reduced using an in situ hydrogen generation procedure (Zn in sulfuric acid solution) to prepare a chitosan-supported palladium catalyst. This catalyst was successfully used to degrade nitrophenol in dilute solutions in the presence of sodium formate as the hydrogen donor. The influence of the initial concentration of nitrophenol and sodium formate was studied in order to determine the minimum molar ratio between these compounds required to achieve complete conversion of the nitrogenous product at two temperatures. Increasing the temperature decreased the excess of hydrogen donor required for complete conversion of nitrophenol. The temperature was also varied between 10 and 60 degreesC in order to determine the activation energy. The pseudo first-order equation was shown to fit degradation kinetics in most cases; however, for some cases it was necessary to use a variable-order equation to model the kinetics. (C) 2004 Elsevier Ltd. All rights reserved.

【 授权许可】

Free