Adsorption Mechanisms of Methylene Blue (MB) Dye on Lignite Coal as Adsorbent

Textile industries are responsible for one of the major environmental pollution problems in the world, because they release undesirable dye effluents which contains dyes mixed with various contaminants. Adsorption is simple and suitable method for the removal of a wide variety of pollutants. The isotherm and adsorption kinetics are the important characteristics that can describe the adsorption mechanism. The objective of this research is to study the adsorption mechanism (isotherms and kinetic model) of MB dye on the adsorption process using the adsorbents made from lignite coal. Different amount of adsorbent (60 mg, 80 mg and 100 mg) was placed in contact with the dye's solution in the required time (5, 10, 20, 30, 40, 50, and 60 min). After the adsorption process was finished, the shaker was turned off and the remained MB dyes concentration was measured using UV-Vis spectrophotometer. The adsorption mechanisme of MB dyes solution fit to Langmuir adsorption isotherm and pseudo second order kinetic model.