Modification of Mesopore Extrudate Gamma Alumina through Thermal Ammonia Treatment

Document Type : Research Article


1 Department of Chemistry, Science and Research Branch, Islamic Azad University, Tehran, I.R. IRAN

2 Department of Chemistry and Chemical Engineering, Buin Zahra Branch, Islamic Azad University, Buin Zahra, I.R. IRAN


A particular type of mesopore extrudates gamma alumina was prepared; which is used as the catalyst in the heavy oil desulfurization unit. Extrudates gamma-alumina support has been made of the boehmite powder from Nephlinsinite mine ores (Surface Area (S.A.) >200 m2/g, Pore Volume (P.V.) =0.48 cm3/g, Average Pore Diameter (A.P.D.) = 8.10 nm); then, many samples of extrudate gamma-alumina (γ-Al2O3) have been created to carry out a research the thermal and ammonia treatments under various operating situations (thermal effect 25,40,60,80 and 100ºC and Consecutive treatments) so as to exhibit the effects of different operating conditions on the pore volume and diameter in the prepared γ-Al2O3 heavy oil catalyst support. Textural properties of catalyst support have been identified by X-Ray Diffraction (XRD), N2-adsorption/desorption, FT-IR, radial strength, and Loss of Ignition (L.O.I) methods. The best effect of the ammonia treatment on the extrudate γ-Al2O3 support was observed after three ammonia treatments at 80ºC; under those circumstances, the resulted catalyst support has the highest amount of resemblance along with the commercial sample (S.A.=215.75 m2/g, P.V.=0.83 cm3/g, A.P.D. =15.49nm).


Main Subjects

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