Microalgae biorefinery in the belt and road initiative: opportunities for green growth

In the context of global energy transformation and climate change, the microalgae industry has emerged as a strategic avenue for promoting green development, driven by its energy conservation, emission reduction, and resource recycling advantages. As a key advocate of the Belt and Road Initiative (BRI), China has increasingly integrated green development into its cooperation framework, fostering the application of microalgae technology in BRI countries and contributing to achieving both environmental and economic goals. This paper reviews the advancements in microalgae technology within bioenergy, high-value product development, and environmental sectors. This review differs from existing studies by systematically linking technological advances in microalgae biorefining with the BRI framework. It examines the entire biorefinery chain—from cultivation to product valorization—while emphasizing improvement measures at each stage, including hybrid cultivation systems to reduce costs, advanced extraction methods to enhance yields, and integrated biorefinery models to optimize resource efficiency. A technology–market matching analysis further reveals that while biofuels face high demand but limited technological maturity, high-value products such as astaxanthin and EPA/DHA show stronger alignment with current market growth. Future efforts should focus on establishing joint pilot-scale facilities, harmonizing green trade standards, and strengthening multilateral cooperation under the BRI. By combining technological innovation with international collaboration, microalgae biorefining can become a key driver of sustainable economic transformation and contribute to achieving global low-carbon goals.