Catalytic Pyrolysis of Bio-waste in Synthesis of Value-added Products: A Systematic Review

Abstract

Bio-waste is a natural waste with significant potential to contribute to net zero emissions targets. However, its efficient valorisation remains a global challenge. Various conversion pathways, including biochemical and thermochemical processes, offer opportunities to produce value-added products that can serve as alternative energy sources and reduce greenhouse gas emissions. Among these, pyrolysis stands out due to its versatility in feedstock compatibility, shorter processing times, and ability to generate a broad spectrum of valuable products with minimal environmental impact. Integration of catalysts into pyrolysis has emerged as a promising strategy for enhancing bio-waste valorisation. This review explores recent advancements and challenges in catalytic pyrolysis of bio-waste, focusing on key process parameters and reactor design. It examines the influence of temperature, heating rate, and reaction time on product characteristics and discusses the latest developments in improving product yield and quality. Catalysts such as zeolites, alkaline earth metals, mesoporous silicas, and biochar are reviewed for their roles in enhancing the pyrolytic process. Environmental benefits include waste reduction, greenhouse gas mitigation, and renewable energy generation, particularly when powered by renewable sources. Challenges such as catalyst deactivation, feedstock variability, and potential environmental risks are addressed, alongside future directions in catalyst design and digital process optimisation.