Chemical Treatment of Banana Blossom Peels Adsorbent as New Approach for Manganese Removal: Isotherm and Kinetic Studies

Abstract

The current study determined the potential of chemical modified banana blossom peels (BBP) as an adsorbent for the removal of manganese (Mn) from water. The BBP adsorbent was characterized using Field Emission Scanning Electron Microscopy (FESEM), Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD) and Brunauer-Emmet Teller (BET). The effects of the solution pH, adsorbent dosage, initial manganese concentration and contact time towards the adsorption process were evaluated in batch adsorption studies. FESEM analysis displayed a deeper dents and rough internal surface that cater for deposition of Mn, while EDX analysis detected the presence of C, O, and Na elements (before adsorption); C, O and Mn (after adsorption). FTIR analysis revealed presence hydroxyl, carboxylic and amino groups which are responsible for the adsorption process. Moreover, XRD analysis showed that the structure of the BBP adsorbent is amorphous. The BET surface area of BBP adsorbent was 2.12 m2/g with the total pore volume of 0.0139 cm3/g and average pore diameter of 64.35 nm. The BBP adsorbent showed promising results of 98% Mn removal at optimum condition of pH 7, 0.5 g (adsorbent dosage), 10 mg/L of Mn initial concentration in 150 min contact time. Adsorption isotherm data were fitted with linear Langmuir and linear Freundlich model best fit with R2 > 0.98, while the adsorption process take place as a function of chemisorption process as determined using linear pseudo-second order kinetics. The maximum desorption rate of Mn was achieved at 92% in the first cycle with recovery rate of 94.18% Mn removal within 30 min using 0.1 M HCl. These findings confirmed the potential BBP as a natural adsorbent for Mn removal as an effective treatment option for enhancing wastewater quality.