Preparation Of Modified Titanium-based Photocatalyst And Study On Denitrification Performance Of Its Oil

The nitrogen content of crude oil in China is generally 0.05%?0.5%.Nitrogen compounds will release toxic gases from petroleum products during use,whichseriously affect the stability of petroleum products,deepen the color of petroleum products and reduce their oxidation resistance.In order to improve the storage stability of refined oil products,and improve economic efficiency,China's current National Sixth Standard for refined oil sets strict requirements on the nitrogen content of fuel products.Denitrification of refined oil is particularly important.The use of photocatalytic technology to denitrify oil products has the advantages of safety,non-toxicity,environmental protection,high stability,high catalytic activity,and low energy consumption,which has attracted widespread attention.In this paper,based on titania-based photocatalyst,a photocatalyst with high efficiency and oil-wet property was prepared by constructing heterogeneous junction and doping nonmetal,which was applied in the field of high efficiency and high performance deep denitrification of petroleum products.?1?Mesoporous titanium dioxide crystals were prepared by a simple hydrothermal synthesis methodusing tetramethyl titanate,and bismuth nitrate as raw materials.X-ray Diffraction?XRD?,Particle Size Distribution,Scanning Electron Microscopy?SEM?,Physical adsorption instrument?BET?,Fourier infrared spectrometer?FTIR?,Chemical adsorption instrument?TPD?and other characterization methods were used to characterize the photocatalyst crystal structure and appearance Appearance,specific surface area,particle size distribution and other properties.Studies have shown that the crystallization reaction is 24hours,and the Ti O₂ obtained by baking at 800°C for 4 hours has high crystallinity,uniform size,and a pore size of 19.72 nm.Higher thermal stability.?2?Ti O₂-Bi VO₄-570-Sepiolite nanophotocatalyst was prepared by hydrothermal synthesis.The surface of Ti O₂-Bi VO₄ grafted silane coupling agent was organically modified and loaded on sepiolite with large specific surface area.The micro-nano structure was constructed to improve the catalytic and oil-wet properties of photocatalysts.The catalysts were characterized by XRD,SEM,energy spectroscopy?EDS?,TPD,BET,FT-IR,etc.,and their photocatalytic oil denitrification performance was evaluated.The results show that when the doped amount of sepiolite is 5%?molar ratio?,the amount of catalyst is 1.5 g/L,and the reaction time is 210 min,the effect of photocatalytic degradation of nitrides is the best,and the denitrification rate It can reach 94.06%,and after the photocatalyst is repeatedly recycled for 5 times,the degradation rate is still high,and the crystal form has not changed significantly.?3?Ti O₂-Bi VO₄-570-RGO photocatalyst was prepared by improved Hummers method.Graphene oxide?RGO?is amphiphilic and photocatalytic,which can improve the transfer channel for electron-hole separation and increase the lipophilicity by reducing the catalyst interface.So the catalytic effect is enhanced.The results showed that when the doping amount of RGO was 10%?molar ratio?,the amount of photocatalyst was 1.5 g/L,and the reaction time was 210 min,the photocatalytic degradation effect reached the best,the denitrification rate of oil products was as high as 90.5%,and the denitrification reaction was in line with the first-order kinetic equation.?4?In order to explore the influence of doped ions on reducing bandgap width and facilitate the recycling of photocatalyst,double-doped Co²⁺/F^--Ti O₂-570-copper mesh photocatalyst was prepared.By constructing micro-nano structure and grafting silane coupling agent on copper network,the surface energy of catalyst was decreased and the oil-wet property was increased.And enhance the photocatalyst acidic site.The catalyst roasted at600°C has good denitrification activity.When the reaction time was 210 min,and the catalyst dosage was 1.5 g/L,the denitrification rate of oil could reach best.