Equilibrium Isotherm Models for the Adsorption of Methylene Blue from Wastewater

Abstract

This research evaluates the equilibrium isotherm models for the adsorption of Methylene Blue (MB) from wastewater by using sawdust red wood and beech wood. The sawdust acts as the low-cost adsorbent by using agriculture by product in order to treat the wastewaters. The objectives for this study are two folds. Firstly, to choose the significant factors (parameters) for the adsorption process. The factors applied in this study are mass of the adsorbent, concentration of the MB solution, pH of the MB solution and contact time between adsorbent and adsorbate. Secondly to determine the best isotherm model on the adsorption process of MB by sawdust. The isotherm models used in this research are Langmuir, Freundlich, Dubinin-Radushkevich and Temkin. Results show that concentration of MB solution is the one and only significant factor for the adsorption process to occur using red wood. Mass of adsorbate, concentration of MB solution and pH of MB solution are the significant factors for the adsorption process to occur using beech wood. The result for the second objective shows that Freundlich is the best model that describe the adsorption process of beech wood as for MB by red wood, Temkin is the best model.

Facile synthesis of a magnetic molecularly-imprinted polymer adsorbent for solid-phase extraction of diclofenac from water

“… 24 A low interaction between the adsorbate and adsorbent molecules at the adsorbent surface is indicated by values <8 kJ mol −1 of the term ( R T / b T ), also referred to as B , which provides information about the heat of adsorption. 25 The value of the constant b T determines the type of sorption process; a b T value of <80 000 indicates physical adsorption. In the present work, the obtained B value was found to be 0.02 J mol −1 and the obtained b T value was 123.9 kJ mol −1 .…”