EFFICIENT REMOVAL OF METHYLENE BLUE FROM AQUEOUS SOLUTION BY ALMOND SHELL ACTIVATED CARBON: KINETICS AND EQUILIBRIUM STUDY.

Almond shell wastes were used to prepare activated carbons with chemical activation by H3PO4, which were tested for the extraction of methylene blue dye from a synthetic liquid solution. The characteristics properties of prepared activated carbon like a functional group and morphological structure were characterized. The prepared activated carbon with a high surface area of 1250 m2/g could be proved as a good adsorbent for the treatment of methylene blue. The batch process was performed to determine the optimum operating parameters for the adsorption of methylene blue (MB). It was seen that the adsorption behaviour of MB was changed by changing the operating parameters like pH of the solution, running time of the experiment, the amount of ASAC dose and initial concentration of MB. At an initial pH of 7, maximum adsorption (100%) was found in running time of 240 min and a dose of 2g/L. In this case, the Langmuir adsorption isotherm model described well in compression to other models and maximum MB absorption uptake (334.40 mg/g) was calculated at a temperature of 30 ºC. The kinetics of adsorption was calculated with different concentrations of MB and it was better represented by the pseudo secondorder model. [ABSTRACT FROM AUTHOR]