Development of activated carbon from sawdust by pyrolysis and methylene blue adsorption

Abstract

Abstract In this study, activated carbon was developed from saw-dust by pyrolysis. The activated carbon was characterized for elemental composition, morphology and surface chemistry. The potential of the prepared activated carbon for the removal of methylene blue (MB) from aqueous solution was investigated. Batch adsorption experiments were conducted to evaluate the adsorption isotherm, kinetic and thermodynamic of MB onto saw-dust activated carbon. The MB removal efficiency was 99.2% and the Lamgmuir isothermal model having correlation coefficient (R 2) of 0.98 gave the best fit. The kinetics of MB adsorption onto activated carbon was described with the pseudo second order model indicates the dominance of chemisorption mechanism. Thermodynamic parameters showed that the adsorption of MB on saw dust activated carbon adsorbent was endothermic in nature and a non-spontaneous process. The activation energy of 34.7 kJ/mol further reveals that the adsorption process was chemisorption. Generally, the results suggest that the saw-dust activated carbon is a viable adsorbent for effective removal of MB from wastewater effluent contaminated with dye.