https://www.sciencedirect.com/science/article/abs/pii/S0306261925019725
Authors: Rui-Long Wang, Ming-Jia Li, Wen-Quan Tao
22 December 2025
Highlights
•Microalgae-based DAC enables scalable and sustainable atmospheric CO₂ removal.
•Key challenges include CO₂ dissolution, mass transfer, and reactor optimization.
•Efficient CO₂ capture and fixation improve energy use and system stability.
•Advances in gas-liquid transfer enhance microalgae DAC performance.
•Scaling and commercialization prospects of microalgae DAC are critically assessed.
Abstract
Direct Air Capture (DAC) technology, particularly utilizing microalgae, has gained significant attention as a promising approach to mitigating atmospheric CO2 levels. Small-scale, modular, and distributed DAC systems offer notable advantages in scalability and adaptability, enabling flexible deployment across diverse environments while supporting sustainable bio-product generation, making them a vital pathway toward carbon neutrality goals. This review aims to address three fundamental scientific issues: (a) enhancing the efficiency, scalability, and durability of CO2 capture processes from low-concentration air, (b) optimizing CO2 fixation methods to overcome challenges such as slow reaction kinetics, high energy demands, and system stability, and (c) achieving efficient integration of capture and fixation processes to ensure energy efficiency and resource sustainability. The review provides a comprehensive analysis of various DAC technologies, evaluating their advantages and limitations to establish a foundation for an in-depth discussion of microalgae-based DAC systems. Key technical challenges, including CO2 dissolution, concentration, and transfer, are thoroughly examined, alongside recent advancements in photobioreactor design, gas-liquid mass transfer enhancements, and process optimization strategies. By synthesizing current research progress and commercial implementation efforts, this work aims to identify pathways for scaling up microalgae DAC technologies while addressing technical and economic bottlenecks. Finally, it evaluates the prospects and challenges of commercializing DAC and microalgae DAC technologies, drawing insights from current applications and commercial projects. This work aims to provide a comprehensive analysis of the technical challenges, optimization strategies, and future potential of DAC technologies, offering insights to guide their practical implementation and scalability.
Source: ScienceDirect