Exploiting agro-waste for cleaner production: A review focusing on biofuel generation, bio-composite production, and environmental considerations

Agricultural by-products such as fruits, vegetables, meat, and poultry can pollute the environment, endangering human and animal health. Most agricultural waste is disposed of without treatment before being burned or deposited in landfills. Furthermore, agro waste has the potential to create a slew of new climate-related challenges by emitting more greenhouse gases into the atmosphere regularly. Around 1 billion tons of agro-waste is generated annually, posing a severe problem on several fronts, including the environment and the economy. Thereby, it is essential to effectively use these wastes during industrial operations to pave the way for producing valuable products, which serves as the conceptual framework. For instance, extracting methane from solid waste in Delhi could provide electricity to 18 million residents. Moreover, the global biofuel demand is expected to increase by 11 million gallons between 2021 and 2026. Effectively processing agro waste with rich carbohydrates such as fruit peels, vegetables, sugarcanes, coconut shells, oil palms, maize, and rice husk can produce biofuels. Furthermore, agro-wastes can be used as filler materials in making biopolymers and bio-composites, which serve as greener alternatives to traditional materials. The effective methods for converting agricultural by-products into biofuels, biocomposite materials, bioenergy, and filler materials have been thoroughly discussed in this review. Furthermore, perspectives ways to improve energy efficiency and techniques to reduce environmental impacts are discussed in the present study.