Ce-doping CuO/HZSM-5 as a regenerable sorbent for Adsorption–Oxidation removal of PH3 at low temperature

Abstract

• Ce-doping Cu/HZSM-5 sorbents were synthesized and used for the removal of PH 3 . • Ce-doping can significantly enhance the adsorption capacity of the Cu/HZSM-5 sorbent. • The interaction between Ce and CuO improves the sorbent physicochemical properties. • The formation of phosphate/phosphide species resulted in the deactivation of sorbent. • The PH 3 capacity was preserved after three times thermal regeneration. A series Ce m Cu n O x /HZSM-5 sorbents were introduced to remove PH 3 in low-temperature and low-oxygen environments. The effects of copper loading and cerium doping on the adsorption–oxidation performance of the sorbents were investigated. Experimental results showed that doping with 1 wt% of cerium (Ce 1 Cu 30 O X /HZSM-5) could significantly improve the performance of the sorbent. The PH 3 breakthrough capacity was identified as 114.36 mg(PH 3 )•g sorbent -1 . In addition, after three thermal regeneration cycles, the sorbent still has ideal performance. X-ray diffractometer (XRD) and X-ray photoelectron spectroscopy (XPS) analyses exhibited that CuO was the main active species, and Ce-doping can increase the chemisorption oxygen on the surface of the sorbent. BET results demonstrated that the introduction of cerium could improve the specific surface area and pore volume of sorbent. Hydrogen temperature-programmed reduction (H 2 -TPR) and scanning electron microscope (SEM-EDS) indicated that cerium species played an important role in uniformly dispersing copper species on the HZSM-5 surface and improving the oxidation performance of sorbent. Moreover, the reaction products and mechanisms were also investigated by XRD, XPS, and in-situ FTIR spectra. The results indicated that the consumption of CuO and the accumulation of phosphorus species (e.g., P, P 2 O 5 , and Cu 3 P) on the surface and inner pores of the sorbent were the primary reasons for the deactivation of the sorbent.