Graft Copolymerization of Glycidyl Methacrylate and Ethylene Glycol Dimethacrylate on Alumina for the Removal of Nitrogen and Sulfur Compounds from Gas Oil

Functionalized polymers were synthesized and applied in removing nitrogen and sulfur compounds from gas oils. In this work, the polyglycidyl methacrylate-co-ethylene glycol dimethacrylate polymer incorporated with tetranitrofluorenone, PGMA-DAP-TENF, was synthesized with and without alumina support. Different techniques were used to characterize the synthesized polymers including Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller method, dynamic light scattering, thermogravimetry/differenial thermal analyzer, carbon hydrogen nitrogen sulfur elemental analysis, and field emission scanning electron microscopy. The performance of the polymer with alumina, Al-PGMA-DAP-TENF, was compared to that without alumina using light gas oil. In addition, heavy gas oil feed was used to confirm the adsorption behavior of both polymers in a higher nitrogen and sulfur environment. The effect of adsorption time and temperature was tested using a 1:5, by weight, polymer to feed ratio. Results have shown that alumina particles enhanced the nitrogen removal efficiency of PGMA-DAP-TENF polymer while sulfur removal efficiency was not affected. The nitrogen removal efficiency of Al-PGMA-DAP-TENF polymer was more than twice that of PGMA-DAP-TENF polymer in LGO feed, and twice that in HGO feed. This was due to the higher surface area of Al-PGMA-DAP-TENF polymer, 202 m²/g, compared to that of PGMA-DAP-TENF polymer, 27 m²/g. In addition, Al-PGMA-DAP-TENF polymer removed more basic nitrogen compounds than PGMA-DAP-TENF polymer. This was attributed to the acidic nature of alumina particles that enhance the adsorption of basic nitrogen compounds present in gas oil feeds.