Sustainable Materials Containing Biochar Particles: A Review.

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Thermochemical decomposition processes like pyrolysis and gasification convert waste (polymers, food, biomass) into valuable products, including char/biochar particles.
• Char/biochar particles possess diverse properties (carbon content, porosity, adsorption) based on their origin and production method.
• Current applications include agriculture, water treatment, and as adsorbents, with emerging use in composites and asphalt.

Purpose of the Study:

• To critically review the advantages and disadvantages of using char/biochar particles as additives and fillers in polymer and biopolymer composites.
• To highlight the potential of waste-derived char/biochar particles in creating sustainable materials.
• To identify limitations, such as color, that affect the broader application of these composites.

Main Methods:

• Review of recent scientific literature on thermochemical decomposition and char/biochar applications.
• Analysis of studies investigating the incorporation of char/biochar particles into polymer and biopolymer matrices.
• Evaluation of reported changes in mechanical, thermal, and physical properties of the resulting composites.

Main Results:

• Incorporating char/biochar particles significantly enhances the elastic modulus, tensile strength, and flame/oxygen resistance of polymer composites.
• Composite ductility is notably reduced with the addition of char/biochar particles.
• The inherent dark coloration of char/biochar particles results in brown-black composites, restricting their use in applications requiring specific aesthetics.

Conclusions:

• Char/biochar particles offer a sustainable route to reinforce polymer composites, improving key performance characteristics.
• The trade-off between enhanced properties and reduced ductility, along with color limitations, needs careful consideration for material design.
• Further research may focus on mitigating drawbacks, such as developing lighter-colored char/biochar or exploring applications where color is not a limiting factor.