Graphene nanosheets from hazardous/solid wastes: An efficient CO2 capture material. Issue 5 (October 2021)

• Record Type: Journal Article
• Authors: Aquatar, Md. Osim; Mankar, Juili S.; Bhatia, Urvashi; Rayalu, Sadhana S.; Krupadam, Reddithota J.
• Is Part Of: Journal of environmental chemical engineering. Volume 9:Issue 5(2021)
• Publication Date: 2021-10
• Subjects: Chemical engineering -- Environmental aspects -- Periodicals; Environmental engineering -- Periodicals; Chemical engineering -- Environmental aspects; Environmental engineering; Periodicals; 660.0286
• DOI: 10.1016/j.jece.2021.105839
• Languages: English
• ISSNs: 2213-2929

Abstract

Abstract: Highly efficient CO2 capture at elevated temperatures has been achieved with a few-layered graphene nanosheets (GNS) prepared from solid waste generated from high energy explosive materials manufacturing industry. These materials were used to adsorb CO2 from simulated industrial flue gases with an aim to reduce CO2 concentration in the atmosphere. The GNS is a microporous material with pore volume of 0.59 cm 3 g −1 and 70% of pores were of average size of 0.55 nm. The surface area of GNS was 964 m 2 g −1 which was reduced to 268 m 2 g −1 when the number of layers in GNS increased to >50. The adsorption capacity of 3.89 mmol g −1 was achieved at 303 K/0.5 bar and this adsorption capacity was further increased to 23.63 mmol g −1 at 303 K/20 bar. The Sips adsorption model was used for evaluating the relationship between surface heterogeneity of GNS and adsorption capacity at temperature. The GNS materials selectively captured CO2 in the presence of gases mixtures (CO2 /N2 and CO2 /CH4 ). The fast adsorption kinetics and recycling stability of GNS for about 20 cycles suggests that the solid adsorbents prepared in this study are efficient and technically feasible to capture CO2 from industrial stacks and other real-life situations. Graphical Abstract: The view of SEM micrograph depicts the layered graphene (a) and the distance between each graphene nanosheet and nanosheet thickness in graphene layered materials was determined by using AFM (b). The molecular model of GNS interaction with CO2 was developed on Gaussian software (c). The adsorption capacity of GNS at different temperatures has an excellent CO2 adsorption capacity (d). ga1 Highlights: Graphene nanosheets (GNS) prepared from hazardous/solid waste by Hydrothermal method. Graphene nanosheets stacking was investigated by using atomic force microscopy. CO2 capture mechanism onto GNS was investigated by using molecular modeling. GNS has high crystallinity with abundant micropores of size (0.6–0.85 nm). High selectivity of CO2 over N2 (CO2 /N2 = 148) and CH4 (CO2 /CH4 = 63).