The Effects of pH and Chelating Agent on Synthesis and Characterization of Ni Mo/γ- Alumina Nanocatalyst for Heavy Oil Hydrodesulfurization

Document Type: Research Article

Authors

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

2 Department of Chemistry, Buinzahra Branch, Islamic Azad University, Buinzahra, I.R. IRAN

Abstract

In this research, various organic additives (as chelating agent) were used to prepare NiMo/ 𝛾-Al2O3 bimetallic catalysts. Then effects of additives and pH variation were studied on textural properties, morphology and size of nanocatalyst particles, interaction and loading of active metals on support. Additionally, this research evaluated the activity of catalysts and compared them with commercial and the catalysts in the absence of additives. The metal oxide nanoparticles were prepared and impregnated on 𝛾-Al2O3 in-situ by using wetness impregnation method, under conditions 60°C and calcination temperature 520°C. The supported nanocatalyst was calcined to remove the volatile materials and gases. The catalysts were characterized by TPR, BET, BJH, AAS, FTIR, SEM and XRD. The prepared nanocatalyst displayed the enhanced catalytic activity for the heavy oil hydrodesulfurization (HDS) containing 21 grL-1 sulfur. At the acidic pH, the activity of the catalyst was promoted by using EDTA compound as a chelating agent. The sulfur content of the feed was decreased up to 2 grL-1 at 380°C, 60 bar, and LHSV 1.5h-1 showing an efficient catalyst with conversion of 90.47%.

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