Biological Treatments for VOC-Contaminated Off-Gas: Advances, Challenges, and Energetic Valorization Opportunities

Volatile organic compounds (VOC) are major contributors to the burgeoning air pollution issue, predominantly from industrial areas, with well-documented environmental and health risks, which demand efficient and sustainable control policies. This review analyzes the current technological challenges and investigates recent developments in biological treatment technologies for VOC-contaminated off-gases, including biofilters, biotrickling filters, and bioscrubber, as well as emerging technologies, such as bioaugmentation and microbial fuel cells (MFCs). Operational performance, economic feasibility, and adaptability to various industrial applications are assessed, alongside opportunities for integration with other technologies, including energy recovery technologies. Biological systems offer considerable advantages regarding cost savings and lower environmental impacts and enhanced operational flexibility, particularly when combined with innovative materials and microbial optimization techniques. Nevertheless, challenges persist, such as choosing the best treatment settings suited to different VOC streams and addressing biofilm control concerns and scalability. Overall, biological VOC treatments are encouraging sustainable solutions, though continued research into reactor design, microbial dynamics, and MFC-based energetic valorization is essential for broader industrial application. These insights cover advancements and highlight the continuous need for innovative prowess to forge sustainable VOC pollution control.