Recent research in utilization of phosphogypsum as building materials: Review

The phosphate industry produces a hazardous byproduct called phosphogypsum (PG). A rising global stockpiling of PG poses severe threats to public health and the environment. Fortunately, recycling this material may be a risk-free and environmentally beneficial answer to this problem. It is necessary to examine its current application and future growth prospects in civil engineering to increase the PG utilization rate. This paper summarizes previous research on reusing PG in building materials. This review article is divided into four essential sections. Firstly, the chemical properties of PG and their treatment methods before using PG in any application are reviewed extensively. Secondly, the strength properties of bricks made with PG and their microstructural characteristics through scanning electron microscope (SEM) and X-ray diffraction (XRD) were reviewed. The third part of this article is about using PG as a substitution for cement and studies the setting time, compressive strength, SEM and XRD of cement mortar. The final section is PG-based concrete and studies concrete specimens' workability, compressive strength, SEM and XRD. The last three sections extensively focused on the microstructural characteristics of the building materials. Following a comprehensive literature search, it was determined that PG could be utilized in the construction industry. Several studies have been performed on using PG in building materials such as bricks, concrete and other materials. However, PG utilization in large-scale practical applications needs better social and political awareness. More money is needed for research and development to free the economy and technology from their shackles. The findings of this review will serve as a foundation for further research and practical applications of PG in environmentally friendly processes.