Synthesis of CoCrNiOx high entropy oxide catalyst and its oxidative desulfurization performance Muntasser Sahib Taha, Hameed Hussein Alwan Applied Chemical Engineering, 2025 The production of ultraclean fuel represents a big challenge for scientists and workers in the petroleum industry because the presence of sulfur in the fuel may have severe consequences for human health and the environment. Oxidative desulfurisation (ODS) is a promising technology when compared with classical hydrodesulfurisation (HDS). In this work, the production of a new catalyst for the ODS process, in which a mixed oxide catalyst was synthesised by mechanochemistry mixing of three metal chlorides (cobalt, nickel, and chromium chlorides), and the atmospheric oxygen was used as an oxidant agent for Iraqi gasoil desulfurisation in an aerobic oxidative desulfurisation (AODS). The prepared catalyst was characterised by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and Energy Dispersive X-ray analysis (EDX). The study included an investigation of the effect of catalyst dosage, reaction temperature, and oxidation time. Response surface methodology (RSM) was used to investigate the performance of the AODS reaction and to evaluate the main impact of the studied variables, as well as the interaction and quadratic effects, for determining the optimum condition. According to the findings obtained from the regression analysis, the experimental data were fitted to a quadratic model with a high correlation coefficient (R² 0.9839), adjusted correlation coefficient (Adj. R² 0.9419), and predicted correlation coefficient (Pred. R² 0.7419). The AODS process was applied with a maximum sulfur removal efficiency of 99% under operating conditions of 0.75 g catalyst dosage, 200 °C reaction temperature, and 60 minutes reaction time. The experimental sulfur removal efficiency was in satisfactory agreement with the predicted efficiency of 98.12%. Analysis of variation (ANOVA) shows that oxidation time is the most significant factor affecting sulfur removal efficiency, followed by reaction temperature and catalyst dosage, as indicated by their F-values.
Enhancing the vanadium recovery from heavy fuel fly ash by using Tri Sodium Citrate as a chelating agent in Alkaline Solution Basheer Hashem Hlihl, Hameed Hussein Alwan, Sata Kathum Ajjam Applied Chemical Engineering, 2025 Sodium carbonate exhibits high selectivity for vanadium and low vanadium recovery rate (43%) from the fly ash of Al-Dura thermal power plant (Baghdad, Iraq) under standard conditions (35°C , 12 hrs, 1M Na2CO3, L/S=10). The recovery increases to 57% in the presence of 0.005M KMnO4. This study explores the role of tri-sodium citrate (0.1M) as a chelating agent in enhancing recovery, achieving up to 85% recovery under the same conditions. Vanadium was precipitated as ammonium metavanadate (NH4VO3) by adjusting pH to 5 using NH4Cl and heating to 50°C for 6 hrs. The precipitate was roasted at 650°C for 2 hrs to obtain vanadium pentoxide (76% purity). The controlling step in vanadium recovery is the chemical reaction rate on the surface of fly ash, as determined by the unreacted-core model. The activation energy for the reaction is (8.47kJ/mole) at a temperature range (35-60°C).
Preparation, Characterization and Activity of CoMo Supported on Graphene for Heavy Naphtha Hydro-Desulfurization Reaction Iranian Journal of Catalysis, 2021
