Catalytic Activity of Synthesized NiMo Catalysts on Walnut Shell Activated Carbon for Heavy Naphtha Hydrotreating

Hydrotreating heavy naphtha using highly active NiMo catalysts on walnut shell activated carbon (NiMo-WAC) nanocatalysts is a new technology for clean fuel production. In this research, pyrolysis of the walnut shell as a scalable, low-cost, and high-yield method was used to synthesize chemically activated carbon in the presence of ZnCl۲, as activating agent. To enhance the catalytic conversion, walnut shell active carbon was functionalized with HCL, HNO۳, and H۲SO۴ to prepare NiMo-WAC۱, NiMo-WAC۲, and NiMo-WAC۳ respectively. These nanocatalysts were synthesized through the incipient wetness impregnation method and characterized by X-Ray Diffraction (XRD), Fourier Transform InfraRed (FT-IR) spectroscopy, Inductively Coupled Plasma-atomic emission (ICP) spectroscopy, Field Emission Scanning Electron Microscopy (FESEM), Brunauer–Emmett–Teller (BET) surface area, Temperature-Programmed Desorption (TPD) and Temperature-Programmed Reduction (TPR) techniques. CHNS (Eager ۳۰۰ for EA۱۱۱۲) was used to study elemental analysis of the walnut shell feedstock used for active carbon synthesis. Different operating parameters including temperature, pressure, LHSV, and H۲/feed (heavy naphtha) ratio for hydrodesulfurization (HDS) reactions were explored by evaluating NiMo-WAC nanocatalysts catalytic activity. HDS of heavy naphtha with ۲۴۹۱ ppm of sulfur in the operation condition of temperature: ۲۹۰ °C, pressure: ۳۰ bar, H۲/oil: ۱۰۰ NL/L, and LHSV: ۳.۳ h-۱ showed considerably higher activity of NiMo-WAC۲ nanocatalyst, less than ۱۰ ppm in the product, than NiMo-γAl۲O۳ as a commercial and reference catalyst, maximum ۱۰۴ ppm in the product, and this is economically valuable.

کلیدواژه ها:

Hydrotreating ، Walnut shell activated carbon ، Nanocatalyst ، Heavy naphtha ، HDS ، NiMo catalysts