The properties of zinc and gallium containing pentasils ? The catalysts for the aromatization of lower alkanes

Investigation of the stability of Zn-based HZSM-5 catalysts for methane dehydroaromatization

“…Xiong et al [58] and Ni et al [43] both observed that the addition of Zn +2 resulted in the elimination of most of the strong surface BAS. Zn loading between 1 and 2 wt% is enough to interact significantly with BAS of HZSM-5, consistent with reported results from IR-spectroscopy [59].…”

Co-cracking of bio-oil model compound mixtures and ethanol over different metal oxide-modified HZSM-5 catalysts

“…As 260 stated by Bhan and Delgass, Me 2+ cations are more easily located 261 inside the zeolite structure when compared with Me 3+ cations dur-262 ing the wet impregnation process because hydrated trivalent 263 cations have an enhanced steric and electrostatic hindrance [31]. The characterization reported by Yakerson et al has also shown 265 that Ga does not penetrate into the zeolite channels and is located 266 as an individual oxide phase on the outer surface of the catalyst, 267whereas Zn tends to distribute itself uniformly throughout the zeo-268 lite channels[32]. Joly et al found that Ga is mainly distributed on…”

“…To further improve the selectivity of 28 aromatics, the influences of different metal oxides loaded onto HZSM-5 were investigated and a range of 29 model compounds were selected and mixed to simulate the distilled fraction of bio-oil. Two model 30 compound mixtures (MCM) were used for co-cracking with ethanol: (1) MCM-1 that contains hydrox- 31 ypropanone, cyclopentanone and acetic acid and (2) MCM-2 that contains hydroxypropanone, cyclopen- 32 tanone, acetic acid, phenol and guaiacol. Co-cracking of MCM-1 and ethanol over ZnO/HZSM-5 and 33 Ga 2 O 3 /HZSM-5 generated higher selectivities of oil phases than that found using HZSM-5 and CuO/ 34 HZSM-5.…”

Non-oxidative propane dehydrogenation over Pt–Zn-containing zeolites

“…Zn-containing zeolites have repeatedly been reported to be attractive catalysts for the conversion of light alkanes into more www.elsevier.com/locate/apcata Applied Catalysis A: General 306 (2006) [85][86][87][88][89][90][91][92][93][94][95][96][97] valuable products such as aromatics and olefins [14][15][16][17][18]. In particular, increased rates for the non-oxidative propane dehydrogenation and selectivities to unsaturated products were observed on zeolite Zn-ZSM-5 (MFI) with respect to the Znfree zeolite H-ZSM-5 [15].…”