Effects of attapulgite addition on the mechanical behavior and porosity of cement-based porous materials and its adsorption capacity

Cement-based porous materials as the current research hotspots is widely used in various industries because of its high early strength and heat resistance. However, it is difficult to control the reaction rate and the balance between strength and porosity. In this study, attapulgite/magnesium phosphate porous composite materials (ATMPPCM) with porosity (79.02%), compressive strength (2.87 MPa) and bulk density (0.77 g/cm(3)) was prepared. The microstructures analysis revealed AT was distributed in the AT-MPPCM framework and coated on the surface to form porous structure. The addition of AT prolonged the casting time to promote the hydration reaction which improved the compressive strength. The AT-MPPCM had the uniformly porous structure with the most probable pore size of about 52 mu m and showed selective adsorption performance for ammonia-nitrogen about 73.42% in the simulated solution. Adding AT effectively improved the water resistance of AT-MPPCM. Compared to the traditional adsorption materials, the preparation technology of AT-MPPCM can greatly improve utilization and facilitate collection. As a result, AT-MPPCM has the potential to be used as filtration and adsorption materials to resolve domestic wastewater.