Adsorption of carbon dioxide by sodium hydroxide-modified granular coconut shell activated carbon in a fixed bed

• Published in: Energy (Oxford) Vol. 77; pp. 926 - 931
• Main Authors: Tan, Y.L., Islam, Md. Azharul, Asif, M., Hameed, B.H.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.12.2014; Elsevier
• Subjects: Activated carbon; Adsorbents; Adsorption; Air pollution caused by fuel industries; Applied sciences; Breakthrough; Carbon dioxide; Chemical engineering; CO2; Dwellings; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Fixed-bed; Fourier transforms; Infrared spectroscopy; NaOH-modified activated carbon; Pollution reduction; Shells; Breakthrough; Adsorption; Fixed-bed; NaOH-modified activated carbon; CO2; Fixed bed; Activated carbon; Pollution control; Carbon dioxide
• ISSN: 0360-5442
• DOI: 10.1016/j.energy.2014.09.079

In the present work, commercial coconut shell activated carbon was impregnated with alkaline NaOH to investigate the efficiency of modified activated carbon for CO2 adsorption in a fixed-bed column adsorption system. The modification parameters, such as the NaOH concentration (24–48%) and dwelling time (1–4 h), were also investigated. The results showed that a 32% NaOH concentration with a 3 h dwelling time provided the best CO2 adsorption capacity. Later, the modified activated carbon was characterized by nitrogen adsorption–desorption, scanning electron microscopy and Fourier transform infrared spectroscopy. The effects of the CO2 % in the feed, the adsorption temperature, the feed flow rate and the amount of adsorbent in the column were investigated in the adsorption experiments. The maximum CO2 adsorption capacity in this study was 27.10 mg/g at 35 °C. This study also suggests that NaOH-modified activated carbon is a state-of-the-art adsorbent for CO2 adsorption. •Coconut shell activated carbon was impregnated with alkaline NaOH.•CO2 was adsorbed in a fixed-bed column adsorption system.•The effects of CO2 concentration, temperature, flow rate and dose are analyzed.•Regeneration of modified activated carbons was effectively tested for ten cycles.