the effects of ph and chelating agent on synthesis and characterization of ni mo/γ- alumina nanocatalyst for heavy oil hydrodesulfurization

In this research, various organic additives (as a 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 a support.  additionally, this research evaluated the activity of catalysts and compared them with commercial and catalysts in the absence of additives. the metal oxide nanoparticles were prepared and impregnated on 𝛾-al2o3 insitu by using the 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, ft-ir, sem, and xrd. the prepared nanocatalyst displayed the enhanced catalytic activity for the heavy oil hydrodesulfurization (hds) containing 21 g/l 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 g/l at 380°c, 60 bar, and lhsv 1.5h1 showing an efficient catalyst with the conversion of 90.47%.