Sustainable biochar from empty fruit bunches: Technological innovations and future perspectives

Indonesia's expansive agricultural landscape generates significant biomass residues, particularly from palm oil production, such as Empty Fruit Bunches (EFB). With 28.65 million metric tons of EFB produced annually, this underutilized resource presents an opportunity for sustainable biochar production. Biochar, a stable byproduct of biomass pyrolysis , offers a durable solution to improving soil quality, enhancing crop productivity, and sequestering carbon in acidic drylands. This review explores pyrolysis technologies for EFB conversion, focusing on heating methods, production scales, and their efficiency. EFB's high lignin content (34.9 %) supports its potential for biochar production, yielding solid residues with beneficial agronomic and environmental properties. However, challenges such as variability in feedstock composition, scalability, and energy efficiency persist. Innovations like microwave-assisted pyrolysis and renewable energy integration for heating show promise in addressing these constraints. The study highlights that optimizing pyrolysis conditions, such as temperature and residence time, alongside exploring continuous production methods and advanced reactor designs, is crucial. Future research must evaluate biochar’s effects on soil health and nutrient cycling through extensive field trials and assess its economic and environmental sustainability. EFB-derived biochar holds the potential to revolutionize sustainable agricultural practices and waste management, contributing to environmental conservation. • Indonesia produces 28.65 million tons of EFB annually, offering a sustainable biochar production potential. • Slow, fast, and microwave-assisted pyrolysis effectively convert EFB into biochar with varying yields. • EFB’s high lignin content (23.89 %) enhances biochar formation, with yield influencedby temperature and heating method. • EFB-derived biochar has applications in soil amendment, fuel, heavy metal adsorption, and composite materials. • Scaling biochar production faces challenges in feedstock variability, process optimization, and quality control.