Photocatalytic Oxidative Desulfurization And Denitrogenation For Fuels Over Ti₃C₂/g-C₃N₄ Composites Under Visible Light Irradiation

At present,gasoline and diesel are still one of the most widely used fuels in China.During the use of fuel oil,the organic sulfides and nitrides in it will also be burned,which will generate harmful gases such as sulfur dioxide and nitrogen dioxide,which will not only cause pollution to the environment,but also seriously threaten human health.Photocatalytic methods can be used to degrade various sulfur and nitrogen compounds in fuel oil.Photocatalytic oxidative desulfurization and denitrification have the advantages of high efficiency and environmental protection,and can meet increasingly stringent international fuel standards.Compared with other materials,semiconductor materials have moderate electrical conductivity,and semiconductor materials will act as catalysts under the irradiation of sunlight,producing redox materials,and after a series of catalytic reactions can convert solar energy into chemistry can.Graphite-phase carbon nitride(g-C3N4),which has been discovered and widely studied in recent years,is a semiconductor material.Its good band gap and its special properties make it widely used in the field of photocatalysis.However,its surface structure type determines its small surface area and high binding law of photo-generated electrons and holes,which limits its photocatalytic activity.Therefore,it is appropriate to modify g-C3N4 to improve its photocatalytic performance.Make it more widely used in actual production and life,maximize social value.In the study of this paper,titanium carbide(Ti3C2)was used to dope the modification of g-C3N4 to solve the problem of low utilization efficiency of g-C3N4 for sunlight.Under visible light irradiation,Ti3C2-doped g-C3N4 was used to study pyridine and thiophene in fuel.The catalytic activity of the catalytic oxidation removal was investigated.The effects of different factors on the activity of Ti3C2 doped g-C3N4 were investigated.The composite materials of Mxene T13C2 and g-C3N4 were simply prepared and used for photocatalytic oxidative denitrification and desulfurization under visible light.The photocatalytic system is suitable for oxidizing small molecules of pyridine and thiophene in the atmosphere without adding molecular O2 or expensive H2O2 oxidant.The structure and photoelectric properties of the photocatalyst were characterized and compared with the original g-C3N4 and Ti3C2.A composite containing 5.0 wt.%Ti3C2 successfully obtained a morphology in which g-C3N4 nanosheets were partially inserted into the T13C2 layer.The intercalation effect accelerates the charge transfer at the g-C3N4 interface and effectively inhibits the recombination of electron-hole pairs.The photocatalytic performance of g-C3N4 for the oxidation of pyridine and thiophene is enhanced,which depends on the improved photoelectric performance after Ti3C2 is embedded.A mechanism is proposed,in which holes act as the main active material in the photocatalytic process,and electrons and O2 in the atmosphere generate superoxide radicals,thereby promoting them.Compared with pure g-C3N4,the composite material of Mxene Ti3C2 and g-C3N4 has better photocatalytic performance,and has significant effects in oxidative desulfurization and denitrification,and the utilization rate of sunlight has also been improved.This provides a new research direction for the preparation of semiconductor materials with high catalytic activity.