DESIGN AND CHARACTERIZATION OF ARDHM CATALYSTS FOR ATMOSPHERIC RESIDUE HYDRODEMETALIZATION IN CRUDE OIL PROCESSING

Abstract

Synthesis and characterization of atmospheric residue hydrodemetalization (ARDHM) catalyst for crude oil processing have been carried out. The catalyst was synthesized by loading of small amount of Ni and Mo metals onto the Indonesian natural zeolite from Klaten (ZA sample). The natural zeolite was treated with

3M HCl solution to produce the ZAA sample. The Ni and Mo metal was impregnated onto the ZAA sample using

(NH₄)₆Mo₇O₂₄.4H₂O followed by Ni(NO₃)₂.6H₂O precursor solution, then calcined at 450ºC for 5 h and reduced at 400ºC for 3 h produced the NiMo/ZAA catalyst. The zeolite samples were characterized by means of total acid amount determined by pyridine vapour adsorption, the TO₄ site (T = Si or Al) analyzed by Infra-Red Spectrometer (IR), Crystallinity by X-ray Diffraction (XRD), and surface performance by Scanning Electron Microscope (SEM), and metal content measured by Atomic Absorption Spectroscopy (AAS). The catalyst activity was tested in hydrodemetalization process using nickel porphyrin, tiophene or pyridine as petroleum residue model compounds carried out at 360, 370, 380 and 390ºC, LHSV 0.2 h^-1. The HCl treatment to the ZA sample caused dealumination, did not defect the crystalline matter and increased total acid amount. Loading of Ni and Mo metal onto the ZAA sample increased acidity, did not defect the crystalline of mordenite and also did not block the zeolite pore. Nickel removal from nickel porphyrin (Np) was easier than N remofal from pyridine; on the other hand, nickel removal from nickel porphyrin was more difficult than S removal from pyridine.  The spent catalyst was deactivated by coke deposition and it can be regenerated and reused.