Enhancement of the activated carbon over methylene blue removal efficiency via alkali-acid treatment

Abstract

The removal of contaminated dyes in wastewater via Activated Carbon (AC) technology is a promising alternative to current conventional pollution-free technologies. Herein, the commercial AC with enhanced adsorption performance capacity were comprehensively investigated via modulating with the alkali-acid treatment. The removal of a highly concentrated methylene blue solution was evaluated via a commercial AC treated with deionized water (AC-DI), potassium hydroxide (AC-KOH) and nitric acid (AC-HNO3). The physicochemical properties of the modified AC were characterized using Fourier Transform Infra-Red (FTIR), X-ray Diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM) and Surface area analyzer and Porosity analysis (SAP). The AC modified with deionized water (AC-DI) exhibited superior adsorption performance with 99% of methylene blue removal within 8 hours. Gratifyingly, the AC-DI has the fastest adsorption uptake within 2 hours in comparison to AC, AC-KOH and AC-HNO3 samples. The superior methylene blue removal performance of AC-DI was attributed to the enhanced surface group functionalization over the surface of AC evidenced from the FTIR analysis. In addition, the better crystallinity of AC-DI sample as shown in XRD and FESEM micrograph analysis does help to improve the adsorption of contaminated dye molecules onto the surface complex of AC, results in a superior rate of methylene blue removal. These results suggest that the alkali-acid treatment shows promises in enhancing the adsorption rate capabilities of commercial AC for the removal of basic dyes from wastewater.The removal of contaminated dyes in wastewater via Activated Carbon (AC) technology is a promising alternative to current conventional pollution-free technologies. Herein, the commercial AC with enhanced adsorption performance capacity were comprehensively investigated via modulating with the alkali-acid treatment. The removal of a highly concentrated methylene blue solution was evaluated via a commercial AC treated with deionized water (AC-DI), potassium hydroxide (AC-KOH) and nitric acid (AC-HNO3). The physicochemical properties of the modified AC were characterized using Fourier Transform Infra-Red (FTIR), X-ray Diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM) and Surface area analyzer and Porosity analysis (SAP). The AC modified with deionized water (AC-DI) exhibited superior adsorption performance with 99% of methylene blue removal within 8 hours. Gratifyingly, the AC-DI has the fastest adsorption uptake within 2 hours in comparison to AC, AC-KOH and AC-HNO3 samples. The superio...