Effect of two-component amorphous silica-alumina (ASA) with different Si/Al molar ratios on hydrocracking reactions for increasing naphtha over NiW/USY-ASA

Abstract

Hydrocracking catalyst NiW/USY-ASA-0.4/2 supported on the composites of USY and two components ASA (Si/Al molar ratio = 0.4 and 2) is reported in this work. The effects of the combination of these two ASAs on the surface structure of the support and the texture, acidity, and catalytic activity of the corresponding catalysts were investigated. The combination of ASA-0.4 and ASA-2 constructs a multistage pore structure and produces new acidic hydroxyl groups by increasing the contact points between silicon and aluminum. The additional acidic hydroxyl groups not only improve the density of BAS and LAS, adjusted the B/L value, but also increase the area of the active adsorption area on the support surface to improve the dispersion of metals. The NiW/USY-ASA-0.4/2 catalyst demonstrated the best catalytic activity compared to the catalyst with single ASA-2 or ASA-0.4 in the process of diesel hydrocracking to naphtha, and its diesel conversion and naphtha selectivity reached 91.6% and 74.0%, respectively. The preparation of the hydrocracking catalyst using multi-component ASA is of great significance to the development of new hydrocracking catalysts.