Effect of chemical modification on dye adsorption capacity of peanut hull

In this paper, the roles played by three major functional groups (amino, carboxyl and hydroxyl groups) in the biomass of peanut hull in adsorption of six dyes were investigated. These functional groups in peanut hull were chemically modified individually to determine their contribution to the adsorption of ionic dyes. The dyes used were methylene blue (MB), brilliant cresyl blue (BCB), neutral red (NR), amaranth (Am), sunset yellow (SY) and fast green FCF (FG). It was found that carboxyl group inhibited the adsorption of anionic: dyes but it was major functional group in the adsorption of cationic dyes, hydroxyl group was important functional group in the adsorption of all six dyes and the effect of methylation of amino group was not significant on the adsorption of six dyes. (c) 2005 Elsevier Ltd. All rights reserved.