Facile Preparation of Ammonium Molybdophosphate/Al-MCM-41 Composite Material from Natural Clay and Its Use in Cesium Ion Adsorption

TLDR: In this paper, an ordered hexagonal mesoporous aluminosilicate matrix (Al-MCM-41) with incorporated ammonium molybdophosphate (AMP) was successfully synthesized by a one-pot synthesis method with natural clay from low-grade potash ores of Qinghai salt lake as the silica and aluminum source.

Abstract: Ordered hexagonal mesoporous aluminosilicate matrix (Al-MCM-41) with incorporated ammonium molybdophosphate (AMP) was successfully synthesized by a one-pot synthesis method with natural clay from low-grade potash ores of Qinghai salt lake as the silica and aluminum source. We introduced a modified “liquid-phase transport” step, which allowed the use of impure natural clay as a starting material to directly produce pure product without sedimentation pretreatment. The resultant product was characterized by X-ray fluorescence (XRF) spectroscopy, FTIR spectroscopy, XRD, TEM, 27Al and 31P magic-angle spinning (MAS) NMR spectroscopy, and N2 adsorption/desorption, which indicated that the AMP was immobilized in the mesoporous structure of Al-MCM-41. The adsorption capacity of the final product for the removal of cesium ions in solution was also investigated. The results suggested that salt lake clay is a promising low-cost precursor for the production of mesoporous aluminosilicate supports through one-pot syntheses, and the final composite material is effective for the adsorption of cesium ions from solutions containing other alkali metal ions.