The Chemical Engineering Department at the College of Engineering, University of Baghdad, held a Ph.D thesis examination titled:
“ Functionalized Biosource Fe/AC Catalyst for Oxidative Desulfurization of Diesel Fuel “
By the student Awad Essa Mohammed and supervised by Prof. Dr. Wadood Taher Mohammed and Co-Supervised Prof. Dr. Saba Adnan Gheni. The examination committee consisted of Prof. Dr. Ammar S. Abbas as Chairman and the membership of Prof. Dr. Hayder A. Rasheid, Prof. Dr. Bashir Y. Sherhan ,Prof. Dr. Sama M. Abdullah, and Asst. Prof. Dr. Sarmad Al-Anssari. After conducting the public discussion and listening to the student’s defense, the thesis was accepted. The thesis was summarized as follows:
The generation of green oil fuel is crucial for preserving a healthy environment and life in the development world. The removal of organic sulfur compounds like thiophenes and their derivatives face the refineries with their greatest obstacles as a result of these strict restrictions. In this study, oxidative desulfurization technique (ODS) was used to remove total sulfur from sour diesel fuel (7361 ppm) using molecular oxygen as oxidant and activated carbon as a catalyst into trickle bed reactor under different levels of operating conditions such as temperature, pressure and liquid hourly space velocity.
Two activated carbons catalysts with 10 wt% Fe as acive metal loaded on the surface of activated carbon,were prepared from olive stones as agricultural wastes by conventional heating (Fe/AC1) (using horizontal tubular furnace under 650 ℃ & 90 min.) and microwave heating method (Fe/AC2) (microcomputer microwave chemical reactor under 565 W & 7 min.), the synthesized catalysts were characterized with specific surface area, Scanning Electron Microscopy coupled with Energy Dispersive X-ray spectrometry, X-ray Diffraction, X-ray Flourescence, Thermal Gravimetric Analysis, Fourier Transform Infrared, Particle size distribution, and Elemental Analysis. The characterization results revealed high surface areas and pore volumes obtained are 1175 m2/g, 1.313 cm3/g, 854 m2/g, 0.995 cm3/g for Fe/AC1 and Fe/AC2 respectively. The SEM-EDX results showed uniform distribution of active metal (10 wt% Fe) for Fe/AC1 better than Fe/AC2. TGA/DTA results revealed the catalyst Fe/AC1 was high stability with low weight losses against high temperatures than Fe/AC2. Based on these findings, it can be concluded that Fe/AC1 showed characterization results better than Fe/AC2 hence, it was used in ODS of sour diesel fuel into batch and trickle bed reactor.
The ODS kinetic of sour diesel fuel with (7361 ppm) initial total sulfur concentration was carried out into batch reactor using molecular oxygen as oxidant and Fe/AC1 as a catalyst under different temperatures (80, 90, 100, 110 ℃) and atmospheric pressure. The results of ODS batch experiments were followed pseudo first order reaction with 51.492 kJ/mol activation energy. The evaluation of the catalyst prepared Fe/AC1 was conducted into a trickle bed reactor with inlet initial total sulfur concentration of sour diesel fuel (7361 ppm) using molecular oxygen as oxidant under different operating conditions, temperature (80, 90, 100, 110, 120 ℃), pressure (1, 3, 5, 7, 9 bar), and liquid hourly space velocity (1, 2, 3, 4, 5 h-1). Based on findings, the maximum desulfurization efficiency obtained was 91.2% under the best experimental conditions of temperature, pressure, and liquid hourly space velocity are 120 ℃, 9 bar, and 1 h-1 respectively. Finally, the desulfurization efficiency response behavior showed the temperature was strong direct proportion, liquid hourly space velocity inversely proportion with slightly pressure direct proportion.
