Study of Methylene blue adsorption on Manganese 1,4-benzene dicarboxylate

E.B. Attahdaniel, C.W. Dikio, P.N. Diagboya, C.Y. Abasi, F. Mtunzi, D. Wankasi, E.D. Dikio
Vaal University of Technology,
South Africa

Keywords: adsorbent, adsorption, dicarboxylate, Manganese-organic framework, methylene blue, reflux, solvothermal

Summary:

This study presents a solvothermal reflux controlled synthesis of Manganese 1,4-benzene dicarboxylate (MnBDC) studied as a potent adsorbent for methylene blue removal from aqueous medium in batch experiments at various contact time, pHs, concentrations and temperatures. The removal of methylene blue was enhanced at pH 2 from 9.10 mg/g to 27.25 mg/g within 120 min. The kinetic study followed the pseudo second order. The Freundlich and Langmuir isotherms adequately described the sorption process A maximum capacity of 58.41 mg/g was obtained from the experimental data for the isotherm. From the thermodynamic parameters’ analysis, ∆Go adsorption of MB on MnBDC was negative. This indicated that the process was spontaneous. However, the values of ∆Go at 300K, 310K and 320K were -85.76, -85.39 and -85.38 kJmol-1 respectively, were more negative than -40 kJmol-1. This implied that the adsorption process involved charge sharing or transfer between the adsorbate to for a coordinate bond which suggested chemisorption dominated the reaction process.