Circular bioeconomy in palm oil industry: Current practices and future perspectives

Malaysia is presently ranked as the second top producer of crude palm oil in the world after Indonesia. The industry is serving as the economic backbone of the country. However, massive criticism and challenges are faced by the palm oil industry with the claims that the industry is causing environmental degradation and negative social impacts. Tremendous efforts have been taken to enhance the sustainability of the palm oil industry in environmental, social, and economic aspects including bioenergy, compost, animal feed production, and replanting of palm oil waste residues. Greener approach on circular bioeconomy is, at present, aimed to be transitioned to the palm oil industry. The concept emphasizes on resource-efficient and waste minimization, aiming to attain a lower production cost, to mitigate the negative environmental impacts, and to conserve the resources. This present review discusses the palm oil supply chain from plantation up to milling operations, current practices of palm oil industry in biomass waste reuse and recycling, and by-products productions including bioenergy generation. The potential and future prospects of full range of biowaste management and its refineries are highlighted comprehensively, including waste-to-energy, waste treatment, and waste valorization for by-products productions. Challenges and potential technological applications are also discussed. To our best knowledge, much is lacking on the circular bioeconomy approach specifically dealt with Malaysian palm oil industry. Therefore, this review serves as a reference for the industrial stakeholders, engineers, environmentalists, researchers, and the government in decision making, policy making, future investment, and innovation advancement.