Synergistic effects of tungsten and phosphorus on catalytic cracking of butene to propene over HZSM-5 Original Research Article

Synergistic catalysis effects among tungsten, phosphorus and HZSM-5 on 1-butene cracking to propene and ethene have been demonstrated by catalytic tests. The tungsten–phosphorus-modified HZSM-5 (W–P/HZSM-5) catalyst, with very low density of acid sites, offers a fairly high conversion rate of butene and selectivity to propene. The status of doped tungsten is characterized by using techniques of D2/OH exchange, NH3 adsorption microcalorimetry, FT-IR spectroscopy, Raman spectroscopy, N2 adsorption and X-ray photoelectron spectroscopy. The tungsten would be monotungstate that interacted with phosphorus before steam treatment and partly congregated to polytungstate species during steaming process at high temperature. The enhanced performance of the catalyst for 1-butene cracking to propene and ethene can be correlated to the synergistic effect between the doped tungsten and phosphorous on the reaction network of the cracking process. The W–P/HZSM-5 is a promising catalyst for the 1-butene cracking to propene and ethene.