Kinetic and Isotherm Studies of Methylene Blue (MB) Dye Adsorption from Textile wastewater onto Metakaolin

Abstract

In this study, Metakaolin was successfully prepared and characterized from Kankara Kaolinite Clay and utilized in the removal of Methylene blue (MB) dye from synthetic Textile wastewater. pH point of zero charge of the Metakaolin was determined from which a working pH was chosen for further studies. Batch adsorption experiment was employed and the effect of process variables; contact time, adsorbent dosage and initial concentration were investigated. Adsorption equilibrium was attained at 60 minutes and adsorbent dosage of 2.0 g of which 99.86% removal of MB was achieved. Kinetic studies showed that pseudo-second order model best described the sorption kinetics with R² value of 0.9695. The adsorption equilibrium data were fitted to adsorption isotherm models, and Langmuir isotherm best described the sorption process as indicated by the R² value of 0.9818. Thus, monolayer of adsorbates molecules (MB) are formed on the adsorbent surface. The maximum adsorption capacity (q_m) of Methylene blue adsorption onto metakaolin was found to be 4.99 mg/g. The research generally revealed that metakaolin is a promising adsorbent that could be utilized in the removal of Methylene Blue (MB) dye and other colored pollutants from aqueous solution.