Natural Products Derived Porous Carbons for CO2 Capture

Abstract

As it is now established that global warming and climate change are a reality, international investments are pouring in and rightfully so for climate change mitigation. Carbon capture and separation (CCS) is therefore gaining paramount importance as it is considered one of the powerful solutions for global warming. Sorption on porous materials is a promising alternative to traditional carbon dioxide (CO₂ ) capture technologies. Owing to their sustainable availability, economic viability, and important recyclability, natural products-derived porous carbons have emerged as favorable and competitive materials for CO₂ sorption. Furthermore, the fabrication of high-quality value-added functional porous carbon-based materials using renewable precursors and waste materials is an environmentally friendly approach. This review provides crucial insights and analyses to enhance the understanding of the application of porous carbons in CO₂ capture. Various methods for the synthesis of porous carbon, their structural characterization, and parameters that influence their sorption properties are discussed. The review also delves into the utilization of molecular dynamics (MD), Monte Carlo (MC), density functional theory (DFT), and machine learning techniques for simulating adsorption and validating experimental results. Lastly, the review provides future outlook and research directions for progressing the use of natural products-derived porous carbons for CO₂ capture.

Keywords: CO2 capture; adsorption; biomass; machine learning; porous carbon; simulation; synthesis.

Figure 1

a,b) Graphs related to the increase in temperature and the amount of CO₂ emissions in recent years (1997‐2022); CO₂ emissions (blue color), global warming (red color).

Figure 2

The different types of post‐combustion CO₂ capture methods.

Figure 3

Illustration of the advantages of choosing natural precursors for synthesizing porous carbons that find use as CO₂ adsorbents.

Figure 4

Various categories of natural carbon‐containing precursor types.

Figure 5

General schematic of the advantages of using biomass.

Figure 6

A variety of porous carbon synthesis methods, from traditional to advanced methods.

Figure 7

Various methods of using KOH chemical reagent to achieve porous carbon. a) schematic of physical and chemical activation; b) By pre‐carbonization, mechanical grinding, and adding urea, Reproduced with permission^{[ 86 ]} Copyright 2020 Wiley; c) By adding Melamine and Sodium thiosulfate, Reproduced with permission.^{[ 87 ]} Copyright 2021, Elsevier; and d) Using pre‐activation+phosphorylation, Reproduced with permission.^{[ 88 ]} Copyright 2021, Elsevier.

Figure 8

Spongy flesh from receptacle and stalk of sunflowers as precursors to synthesize porous carbons with and without KOH activation in argon atmosphere, Reproduced with permission^{[ 50b ]} Copyright 2019, Elsevier.

Figure 9

Various methods of porous carbon synthesis using HTC, a) Using ZnCl₂ and KOH after hydrothermal. Reproduced with permission^{[ 102 ]} Copyright 2017, Elsevier, and b) Using ammoxidation and KOH, Reproduced with permission^{[ 103 ]} Copyright 2018, Elsevier.

Figure 10

Cocoa bean shells derived porous carbon with high S_BET (2000 m². g⁻¹) synthesized by [Bmim] [FeCl₄] and CO₂ activation. As shown, the synthesized porous carbon has a remarkable CO₂ capture as high as 4.4 mmol g⁻¹ at 25 °C under 1 bar, Reproduced with permission^{[ 105 ]} Copyright 2020, Royal Society of Chemistry.

Figure 11

Molten salt synthesis at 480 °C using ZnCl₂ Reproduced with permission^{[ 80 ]} Copyright 2011 Royal Society of Chemistry.

Figure 12

Schematic of self‐activation method. a) General schematic of traditional self‐activation method under inert gases or through self catalytic‐metal. Reproduced with permission^{[ 86a ]} Copyright 2020 Wiley; b) Mechanism of self‐activation method includes pore expansion and pore combination Reproduced with permission^{[ 112 ]} Copyright 2015 Royal Society of Chemistry; c) New green self‐activation method using a pump and gas flows in a closed cycle Reproduced with permission^{[ 114 ]} Copyright 2022 Elsevier.

Figure 13

Schematic illustration of the porous carbon synthesis methods using different types of templates.

Figure 14

a) General schematic of the microwave method: Investigating the differences between the type of heat transfer in traditional methods and the microwave method, Reproduced under the term of the Creative Commons CC BY license.^{[ 126 ]} Copyright 2015, The Authors, published by SpringerNature. b) Schematic of plasma method for modifying porous carbon surface.

Figure 15

Overview of various components decomposition during pyrolysis: TG analysis has been performed for lignocellulosic biomass‐derived porous carbon, Reproduced with permission^{[ 140 ]} Copyright 2012 Royal Society of Chemistry.

Figure 16

Types of adsorption isotherms based on the International Union of Pure and Applied Chemistry (IUPAC) classification, Reproduced under the term of ther Creative Commons Attribution 4.0 International License.^{[ 161 ]} Copyright 2018, The Authors, published by Scientific Research Publishing Inc.

Figure 17

Different types of morphologies for porous carbons obtained using FESEM. From left to right) Reproduced with permission.^{[ 187a ]} Copyright 2018, Elsevier;^{[ 187b ]} Copyright 2021, American Chemical Society;^{[ 187c ]} Copyright 2018 Elsevier; reproduced under the term of the Creative Commons CC BY license^{[ 187d ]} Copyright 2020, The Authors, published by MDPI; reproduced with permission.^{[ 187e ]} Copyright 2019, ACS.

Figure 18

a) HRTEM micrographs of graphitized structure, Reproduced with permission^{[ 190 ]} Copyright 2018 Elsevier, and b) wormhole‐like pore structure Reproduced with permission^{[ 191 ]} Copyright 2020 Elsevier.

Figure 19

The general mechanism of physical adsorption of CO₂ through diffusion (induction) in interconnected porosity or through functional groups.

Figure 20

Overview of the factors affecting the sorption of CO₂ on natural wastes‐derived porous carbons.

Figure 21

Schematic of porous carbon synthesis using metals nitrate Reproduced with permission^{[ 259 ]} Copyright 2018, Elsevier.

Figure 22

The role of Fe in reducing the kinetic rate of CO₂ uptake, Reproduced with permission^{[ 196 ]} Copyright 2020 Elsevier.

Figure 23

Overview of CO₂ and N₂ properties to better understand the gas separation process.

Figure 24

Overall comparison of the results of CO₂ adsorption and selective separation obtained from simulation with the results obtained from the experimental condition in different porosity sizes. a) Reproduced with pemission.^{[ 217 ]} Copyright 2020, Elsevier. b) Reproduced with permission.^{[ 292 ]} Copyright 2021, Elsevier.

Figure 25

Investigation of effective parameters on CO₂ uptake by molecular dynamics simulation.

Figure 26

The summary of DFT calculation conducted on porous carbons.

Figure 27

Schema of the supervised ML algorithm for CO₂ capture using natural porous carbon adsorbents.