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. 2023 Jan 13;8(5):4802-4812.
doi: 10.1021/acsomega.2c06955. eCollection 2023 Feb 7.

Impact of KOH Activation on Rice Husk Derived Porous Activated Carbon for Carbon Capture at Flue Gas alike Temperatures with High CO2/N2 Selectivity

Rajib Nandi  1   2 , Mithilesh Kumar Jha  1 , Sujit Kumar Guchhait  2 , Debanjan Sutradhar  1   2 , Shashikant Yadav  1
Affiliations

Impact of KOH Activation on Rice Husk Derived Porous Activated Carbon for Carbon Capture at Flue Gas alike Temperatures with High CO2/N2 Selectivity

Rajib Nandi et al. ACS Omega. .

Abstract

Metal-free porous activated carbon is an effective alternative to capture CO2 due to its high surface area and textural advantages. In this regard, the present research work explores a suitable method for producing activated porous carbon with a high specific surface area through a two-step reaction involving rice husk and KOH at 600 °C for 1 h to capture CO2. By varying the ratio of rice husk biomass to KOH, the texture and specific surface area of the activated porous carbon has been altered. A high surface area of ∼755 m2/g and a micropore volume of 0.243 cm3/g have been observed in the porous carbon produced with a KOH/biomass weight ratio of 3 (PAC2). Nitrogen contents in PAC1 and PAC2 were approximately 2.27 and 2.71 atom %, respectively. When compared with other materials, PAC2 has the highest CO2 adsorption capability, reaching up to 3.13 mmol/g at 0 °C and 1.55 mmol/g at 50 °C. The isosteric heat of adsorption confirms the presence of both physisorption and chemisorption. The materials turn out to be highly CO2/N2 selective, with the highest selectivity of 131, proving that the samples are potential materials for capturing CO2 from flue gases. These findings unequivocally show that porous activated carbon can be used to make CO2 adsorption efficient, inexpensive, and, more importantly, extremely effective.

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Conflict of interest statement

The authors declare no competing financial interest.

Figures

Figure 1
Figure 1
SEM images of (a) RHBC and (b, c) activated carbons PAC1 and PAC2, respectively, prepared with different KOH-to-biomass ratios at a temperature of 600 °C.
Figure 2
Figure 2
XRD patterns of (a) rice husk and RHBC and (b) RHBC and activated carbons (i.e., PAC1 and PAC2) prepared with different KOH/biomass ratios at a temperature of 600 °C.
Figure 3
Figure 3
TGA–derivative thermogravimetry (DTG) analysis of (a) rice husk (RH) and (b) rice husk biochar (RHBC).
Figure 4
Figure 4
N2 adsorption–desorption isotherms of (a) rice husk biochar (RHBC) and (b) activated carbons (i.e., PAC1 and PAC2) prepared with different KOH/biomass ratios at the temperature of 600 °C. (c) Pore size distribution of RHBC, PAC1, and PAC2.
Figure 5
Figure 5
N 1s XPS spectra of (a) RHBC, (b) PAC1, and (c) PAC2 samples.
Figure 6
Figure 6
(a) Survey spectra of RHBC, PAC1, and PAC2 samples. O 1s XPS spectra of (b) PAC1 and (c) PAC2. (d–f) C 1s XPS of RHBC, PAC1, and PAC2, respectively.
Figure 7
Figure 7
CO2 adsorption isotherms of the rice husk-derived carbons of (a) RHBC, (b) PAC1, and (c) PAC2.
Figure 8
Figure 8
Langmuir, Freundlich, and Toth isotherm model fits of the rice husk-derived carbon of (a) PAC1 and (b) PAC2.
Figure 9
Figure 9
Comparison of CO2 uptake of the rice husk-derived carbons of RHBC, PAC1, and PAC2 under different conditions.
Figure 10
Figure 10
Isosteric heat of adsorption of the rice husk-derived carbons of RHBC, PAC1, and PAC2.
Figure 11
Figure 11
(a) Toth fit and (b) IAST selectivity of rice husk-derived carbons of PAC1 and PAC2.
See this image and copyright information in PMC

References

    1. Trends in Atmospheric Carbon Dioxide, Earth System Research Laboratory, National Oceanic & Atmospheric Administration. Https://Www.Noaa.Gov/News-Release/Carbon-Dioxide-Now-More-than-50-Higher... (accessed Sept 26, 2022).
    1. Yuan X.; Kumar N. M.; Brigljević B.; Li S.; Deng S.; Byun M.; Lee B.; Lin C. S. K.; Tsang D. C. W.; Lee K. B.; Chopra S. S.; Lim H.; Ok Y. S. Sustainability-Inspired Upcycling of Waste Polyethylene Terephthalate Plastic into Porous Carbon for CO2capture. Green Chem. 2022, 24, 1494–1504. 10.1039/d1gc03600a. - DOI
    1. Thengane S. K.; Bandyopadhyay S. Biochar Mines: Panacea to Climate Change and Energy Crisis?. Clean Technol. Environ. Policy 2020, 22, 5–10. 10.1007/s10098-019-01790-1. - DOI
    1. Gupta A.; Paul A. Carbon Capture and Sequestration Potential in India: A Comprehensive Review. Energy Procedia 2019, 160, 848–855. 10.1016/j.egypro.2019.02.148. - DOI
    1. Yu C. H.; Huang C. H.; Tan C. S. A Review of CO2 Capture by Absorption and Adsorption. Aerosol Air Qual. Res. 2012, 12, 745–769. 10.4209/aaqr.2012.05.0132. - DOI