Removal of a cationic dye from water by activated pinecones

Abstract

Adsorption of a cationic phenothyazine dye, Methylene Blue onto activated carbon prepared from pinecones was investigated. The parameters contact time, dye concentration and pH were varied. The kinetic data were found to follow closely the pseudo-second-order kinetic model. The equilibrium data were best represented by the Langmuir isotherm with a maximum adsorption capacity of 233.1 mg g(-1). The adsorption was favored by using a higher solution pH. Textural analysis by nitrogen adsorption was used to determine the specific surface area and pore structure of the obtained carbon. Boehm titrations revealed that carboxylic groups were present in a high degree on the carbon surface. The results indicate that the presented method for activation of pinecones could yield activated carbon with significant porosity, a developed surface reactivity and a considerable adsorption affinity toward the cationic dye Methylene Blue.