Preparation of bifunctional NiPb/ZnO-diatomite-ZSM-5 catalyst and its reactive adsorption desulfurization coupling aromatization performance in FCC gasoline upgrading process

• Published in: Fuel (Guildford) 2013-02, Vol.104, p.201-207
• Main Authors: Zhang, Ke, Liu, Yunqi, Tian, Shuang, Zhao, Enhong, Zhang, Jingcheng, Liu, Chenguang
• Format: Article
• Language: English
• Subjects: Applied sciences; Aromatization; Catalyst; Coupling process; Crude oil, natural gas and petroleum products; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Fuels; Processing of crude oil and oils from shales and tar sands. Processes. Equipment. Refinery and treatment units; Reactive adsorption desulfurization
• ISSN: 0016-2361; 1873-7153
• DOI: 10.1016/j.fuel.2012.08.052

► Pb-modified Ni/ZnO adsorbent can efficiently suppress olefin saturation. ► Pb-modified Ni/ZnO-DZSM-5 catalyst exhibits high aromatization performance of olefin. ► Coupling process can achieve ultra deep desulfurization without loss of octane number. A bifunctional NiPb/ZnO-diatomite-ZSM-5 (NiPb/ZnO-DZSM-5) catalyst for FCC gasoline upgrading by reactive adsorption desulfurization (RADS) coupling olefin aromatization function was prepared by wet-mixed squeezed method to avoid octane number loss from olefins hydro-saturation in traditional RADS processing. The crystalline structure and textural property of as-prepared adsorbents/catalysts were characterized by X-ray powder diffraction (XRD) and N2 adsorption analysis, respectively. Adsorption desulfurization and aromatization activities evaluation of FCC gasoline and model gasoline over different adsorbents/catalysts were investigated. The results showed directly introducing the composite of aromatization catalyst into the reactive adsorption desulfurization adsorbent is difficult to conquer the loss of gasoline octane number from olefin saturation and sustain the ultra deep desulfurization ability of the reactive adsorption desulfurization process simultaneously. However, the prepared Pb-modified Ni/ZnO-DZSM-5 catalysts (by introducing second metal into Ni/ZnO-DZSM-5 catalyst), exhibited improved aromatization and desulfurization performance with low octane number loss. The aromatic concentration in products increased with the additive amount of ZSM-5 in catalyst composition, meanwhile, as the adding Pb cannot destroy the original crystalline phase, Pb-modified NiPb/ZnO-ZSM-5 catalyst can inhibit olefin saturation effectively with high desulfurization activity. Regenerated bifunctional NiPb/ZnO-DZSM-5 catalyst also exhibits excellent desulfurization and aromatization performance with no octane number loss.