Toxic PH3 Catalytic Decomposition and High Purity Phosphorus Production by Amorphous Co-Based Alloy Nanomaterials

PH3 is a by-product of sodium hypophosphite industry, and is a high toxic waste gas for human and environment. Meanwhile, PH3 can be decomposed to high purity yellow phosphorus (P-4), which is expensive and widely demanded in industries, such as the high-quality micro-electronic production. Therefore, catalytic decomposition of PH3 into yellow phosphorus is of economic benefits and environmental significance. Co-based alloys nanomaterials in amorphous form were found to exhibit excellent catalytic activities for PH3 decomposition in our investigation. In the paper, nano-sized CoB, CoP, CoBP amorphous alloys particles were prepared and their chemical compositions and structures were characterized by multiple analysis and characterization technologies, including ICP, DSC, SEM, TEM, X-ray diffraction, and BET analysis. The as-prepared Co-based amorphous alloy catalysts performed perfect catalytic activities for PH3 decomposition under various temperatures. Depositing the CoP amorphous alloy on the support (TiO2) significantly improved its thermal stability, surface area and anti-aggregation property, which were mainly attributed to the high dispersion of CoP alloy particles on the support. The catalytic activities of these as-prepared nano-catalysts were compared and they follow the sequence of CoB>CoBP>CoP/TiO2>CoP. CoB exhibited the best PH3 decomposition property, with 98.4% of PH3 decomposed at 723 K. Overall, the Co-based nano-catalysts exhibited a unique property and a high potential in industrial application of PH3 decomposition to yellow phosphorus, which has both important economic benefits and environment significance.