Bioprocess-based recycling of phosphogypsum for sustainable product development

Phosphogypsum (PG) is a large-scale industrial by-product of phosphoric acid production, representing both a significant environmental burden and a potential secondary resource within circular bioeconomy frameworks. Despite growing interest in bioprocesses for PG valorization, comprehensive reviews integrating bioconversion pathways with sustainable product outcomes remain limited. This review provides a critical analysis of the current state of bioprocess-based PG recycling aimed at sustainable product development. This review provides a critical analysis of the current state of bioprocess-based PG recycling with a focus on sustainable product development. A structured review with bibliometric analysis of peer-reviewed literature indexed in Scopus and Web of Science was conducted using VOSviewer software to identify key research trends, dominant bioprocess routes, and major technological challenges associated with PG utilization. The role of PG-derived substrates in supporting microbial growth and bioproduction is analyzed in the context of ecosystem services and resource recovery, while current biotechnological applications are critically assessed with respect to performance limitations, process bottlenecks, and scale-up constraints. Based on the synthesis of available evidence, the most promising directions for integrating PG into bioprocess-based production systems are identified. The review further proposes a unified conceptual framework linking PG recycling, bioprocess engineering, and sustainable product development, and outlines future research priorities required to advance PG valorization from laboratory-scale studies toward industrial implementation.