Continuous, Large-Scale, and High Proportion of Bioinspired Phosphogypsum Composites via Reactive Extrusion

Abstract

Biological matter evolution provides an idea for the human design and synthesis of new materials. However, biomimetic materials only stay in laboratory-scale models, and their large-scale industrial applications are yet to be realized. Here, inspired by nacre’s architecture, we report a continuous, large-scale method to fabricate phosphogypsum composites by reactive extrusion strategy. After curing for seven days, with more than 50 wt% of beta-hemihydrate phosphogypsum (β-HPG), the compressive strength and softening coefficient were 24.98 MPa and 0.78, increasing by 110.0% and 20.0%, respectively, compared to the pouring method. The results show that the screw extrusion process can improve the mechanical strength and waterproof properties of β-HPG hydration specimens without any special chemical admixtures and cements.

Study on the Mechanical Properties of Cast-In-Situ Phosphogypsum as Building Material for Structural Walls

“…The work [ 11 ] describes a method of successfully preparing high-quality nano-calcium fluoride in aqueous solutions by direct precipitation using calcined phosphogypsum as a raw material. The work [ 12 ] introduces a continuous and large-scale method for manufacturing phosphogypsum composites through a reactive extrusion strategy. The work [ 13 ] proposed a simple and efficient approach for the high-purity CaSO 4 ·2H 2 O (DH) whiskers and α-CaSO 4 ·0.5H 2 O (α-HH) whiskers derived from phosphogypsum (PG).…”