Ceramic membrane technology for the separation and purification of bioactive compounds: A critical review of applications, diafiltration modeling, and fouling prevention

Bioactive compounds are essential for human health and safety, yet their separation and purification pose significant challenges due to the diversity and complexity of their sources and components. Membrane separation technology has gained considerable attention in this field, with ceramic membranes standing out due to their narrow pore size distribution, remarkable chemical and thermal stability, low fouling propensity, and extended lifespan. Given the attractiveness of this technology, the performance of ceramic membranes is critically reviewed with a focus on bioactive compounds. This review covers typical applications, including both pretreatment and precision separation, such as clarification and recovery, proteins-based compound fractionation, and oligosaccharides purification. Additionally, diafiltration, commonly used to enhance the purity of target compounds, is complex and requires further optimization. The role of diafiltration and its modeling for ceramic membranes in process design is explored. Importantly, this review discusses various surface engineering design strategies, including doping, co-deposition, surface coating, and chemical grafting, which can impart multifunctionality and mitigate fouling. Other strategies to prevent or alleviate fouling, such as pretreatment, operating parameter optimization, strengthening promotion, and fouling cleaning, are also reviewed. Finally, the review concludes by highlighting future research directions, such as developing cost-effective ceramic membranes, establishing a diafiltration model that considers membrane parameters using artificial intelligence (AI) approaches, and implementing effective antifouling modifications without sacrificing permeability.