Synthesis of a novel zeolite W and application in the catalyst for FCC gasoline hydro-upgrading

• Novel zeolite W was firstly synthesized using solid silica-alumina microspheres.
• The synthesis conditions of zeolite W were investigated systematically and optimized.
• Zeolite W based catalyst exhibited better HDS and RON preservation performance.
• The synergy between the texture and acidity of zeolites W/L improved the activities.

Zeolite W was synthesized via the hydrothermal crystallization method by using KOH as the potassium and alkaline source, and a kind of cheap solid silica-alumina microsphere as the unique silica and alumina sources. The effects of synthesis factors on the formation of zeolite W were systematically investigated. The corresponding CoMo/γ-Al2O3-L/W catalysts with different molar ratios of zeolite L/W were prepared for the hydro-upgrading of fluid catalytic cracking (FCC) gasoline. The as-synthesized zeolite W and catalysts were characterized by means of XRD, SEM, pyridine-FTIR, UV–vis DRS and nitrogen adsorption. When the ratio of zeolite W and L was 1:1 (Cat. 3), the catalyst exhibited the best catalytic performances for both hydrodesulfurization (HDS) and preserving research octane number (RON). The sulfur content of hydrogenated gasoline is 5.7 mg/L, and the loss of RON is only 1.22 units compared with the RON of feedstock. The catalysts containing the zeolite W and L showed the excellent performances for deep desulfurization, aromatization, isomerization and RON preservation in the hydro-upgrading process of full-range FCC gasoline. The synergy of zeolite W and zeolite L could adjust the functionality balance between the selective hydrogenation, aromatization and isomerization.

A novel microporous zeolite W was successfully synthesized using low-cost solid silica-alumina microspheres to be the unique silica and alumina sources. The corresponding catalyst of CoMo/γ-Al2O3-L/W with the zeolites L/W (molar ratios 1:1) exhibited the best catalytic performances for both HDS (98.2%) and research octane number (RON) preservation (1.22 units loss), since the incorporation of zeolites W and L into the support improved the excellent balances of deep desulfurization, aromatization, isomerization and RON preservation ability in the hydro-upgrading process of full-range FCC gasoline.Figure optionsDownload high-quality image (255 K)Download as PowerPoint slide