Adsorption of methyl red by water-hyacinth (Eichornia crassipes) biomass

The surface characteristics and adsorbent properties of biomass, obtained from low-cost and environmentally problematic water hyacinth. were determined. Optimum conditions for the elimination of the industrial dye Methyl Red (1) from aqueous solution were established by means of a batch adsorption technique. The ultimate adsorption capacity of water-hyacinth biomass in terms of the elimination of 1 was calculated from a Langmuir-type isotherm as 8.85 x 10(-2) mol g(-1) at 30 degrees and at an optimum solution pH of 8.0. Dye elimination was found to be associated with strong electrostatic forces (physisorption). the overall process being slightly endergonic (Delta G>0). Our study shows that water hyacinth has a great potential of removing color from wastewater and other dye-polluted aquatic systems.