Biopolymeric Nanocomposites for CO2 Capture

Abstract

Carbon dioxide (CO₂) impacts the greenhouse effect significantly and results in global warming, prompting urgent attention to climate change concerns. In response, CO₂ capture has emerged as a crucial process to capture carbon produced in industrial and power processes before its release into the atmosphere. The main aim of CO₂ capture is to mitigate the emissions of greenhouse gas and reduce the anthropogenic impact on climate change. Biopolymer nanocomposites offer a promising avenue for CO₂ capture due to their renewable nature. These composites consist of biopolymers derived from biological sources and nanofillers like nanoparticles and nanotubes, enhancing the properties of the composite. Various biopolymers like chitosan, cellulose, carrageenan, and others, possessing unique functional groups, can interact with CO₂ molecules. Nanofillers are incorporated to improve mechanical, thermal, and sorption properties, with materials such as graphene, carbon nanotubes, and metallic nanoparticles enhancing surface area and porosity. The CO₂ capture mechanism within biopolymer nanocomposites involves physical absorption, chemisorption, and physisorption, driven by functional groups like amino and hydroxyl groups in the biopolymer matrix. The integration of nanofillers further boosts CO₂ adsorption capacity by increasing surface area and porosity. Numerous advanced materials, including biopolymeric derivatives like cellulose, alginate, and chitosan, are developed for CO₂ capture technology, offering accessibility and cost-effectiveness. This semi-systematic literature review focuses on recent studies involving biopolymer-based materials for CO₂ capture, providing an overview of composite materials enriched with nanomaterials, specifically based on cellulose, alginate, chitosan, and carrageenan; the choice of these biopolymers is dictated by the lack of a literature perspective focused on a currently relevant topic such as these biorenewable resources in the framework of carbon capture. The production and efficacy of biopolymer-based adsorbents and membranes are examined, shedding light on potential trends in global CO₂ capture technology enhancement.

Keywords: CO2 capture; adsorption capacity; biopolymer; carbon dioxide; nanocomposite materials.

Figure 1

Schematic illustration of CO₂ capture and conversion methodology and utilization [11].

Figure 2

Advanced materials for CO₂ capture post-combustion methods.

Figure 3

Gas adsorption on microporous biopolymer.

Figure 4

Flowchart of the cellulose synthesis process [49].

Figure 5

Schematic reaction between amine groups and CO₂ and the influence of humidity content.

Figure 6

Flowchart of sodium alginate synthesis via two typical processes: calcium salt precipitation (blue boxes) or acidification (orange boxes).

Figure 7

Flow diagram of chitosan synthesis and possible hydrolysis in the corresponding oligomers or monomers [93].

Figure 8

Immobilization techniques: (a) adsorption, (b) surface covalent bonding, (c) encapsulation within a polymer, and (d) cross-linking.

Figure 9

Flowchart for the extraction of gel and refined carrageenan from seaweeds [110].