The Synthesis of NiY Zeolite via the Acid Hydrolysis of Ethyl Silicate and Its Catalytic Performance in the Degradation of Benzyl Phenyl Ethers

The siliceous precursor was hydrolyzed from tetraethylorthosilicate (TEOS) under acidic conditions, followed by the addition of sodium aluminate and sodium hydroxide. Y zeolite was subsequently obtained through hydrothermal crystallization under alkaline conditions. Key synthesis parameters, including reactant molar ratios, crystallization temperature, and time, were systematically varied to optimize the synthesis conditions. The synthesized products were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), nitrogen adsorption analysis, and inductively coupled plasma (ICP) elemental analysis. Well-crystallized Y zeolite with a silica-alumina ratio (SAR) of 5.55 was successfully synthesized via TEOS hydrolysis catalyzed by sulfuric acid at a low crystallization temperature of 85 °C. The catalytic performance of benzyl phenyl ether, a lignin model compound, over NiY catalyst was evaluated in a high-pressure reactor. The results indicate that the catalytic efficiency of Y zeolite synthesized using TEOS as the silicon source under acidic hydrolysis conditions is significantly superior to Y zeolite prepared using alkaline silica sol as the silicon source.