Recent Advancements in the Generation of Biochar Bioeconomy from Agricultural Biomass Waste and Sustainable Applications in Climate-Smart Agriculture

Transforming agricultural biomass into biochar-based bioeconomy is a promising strategy for waste valorization, reducing land degradation, improving soil fertility, leveraging machine learning, mitigating climate change, and advancing different technological readiness levels. The current article examines the potential of major agricultural residues, encompassing both lignocellulosic and non-lignocellulosic crop residues, with respect to their composition, availability, and efficiency as biochar feedstocks. An extensive analysis of thermochemical agricultural waste conversion processes, including pyrolysis, gasification, hydrothermal carbonization, and torrefaction was made to emphasize the critical process components affecting sustainable biochar yield and quality improvement. The study reviews diverse biochar synthesis reactions, bond cleavage, and aromatic carbon networks, assessing surface chemistry dynamics using advanced tools and techniques like Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and Brunauer-Emmett-Teller analysis. The article further discusses on post-biochar production methodologies, focusing on agroeconomic and sustainable intensifications of biochar in climate-smart agro-ecosystems for improving soil health, fertility, pH optimization, greenhouse gas mitigation, and carbon sequestration potential. Microbial colonization on biochar surface enhances native microbial population dynamics in soil, releases essential nutrients like nitrogen and phosphorus, and aids in remediating emerging contaminants in soils and environment. Data visualization techniques reveal techno-economic aspects of scientific research output of biochar generation, revealing trends and current research patterns, more accurately and precisely. The multidimensional use efficiency of biochar, along with appropriate life-cycle assessments and commercialization potential, needs to be reconsidered, ensuring wider acceptance of biochar in precision agriculture. The study additionally describes the current challenges in biochar production and sustainable applications, including the production process and dose optimization as well as regulatory gaps and challenges. It suggests possible improvements in reactor design and increased production and use efficiencies related to nanostructured biochar, thereby integrating chemistry, biotechnology, and sustainability in the management of major agricultural wastes.