Adsorption of methylene blue from aqueous solution by chemically treated water hyacinth

Author: El-Khaiary Mohammad   Gad Falah   Mahmoud Mahmoud   El-Din Samy Hossam  

Publisher: Taylor & Francis Ltd

ISSN: 0277-2248

Source: Toxicological and Environmental Chemistry, Vol.91, Iss.6, 2009-08, pp. : 1079-1094

Disclaimer: Any content in publications that violate the sovereignty, the constitution or regulations of the PRC is not accepted or approved by CNPIEC.

Previous Menu Next

Abstract

Water hyacinth (WH), an aquatic plant macrophyte, was investigated for its ability to perform as a suitable adsorbent for methylene blue (MB) from aqueous solution. The non-living biomass of WH was subjected to several chemical treatments, namely, washing with hot water, washing with hot dilute HCl, soaking in NaOH, soaking in HNO3, and sulfonation. The system variables studied also include pH and MB concentration. The Langmuir isotherm was found to represent the measured adsorption data well except for WH soaked in NaOH, which was found to be better represented by the Freundlich isotherm. Values of the dimensionless separation factor, KR, indicated that the adsorption systems in this study are all favorable. Values of the first layer of adsorption were calculated by the non-linear multilayer adsorption model, and the specific surface area values were found to be high and comparable to commercially activated carbons.