【作者】 赵保林；

【导师】 那平；

【作者基本信息】 天津大学 ， 化学工程， 2007， 硕士

【摘要】 生产和使用环境友好的超低硫、零排放清洁燃料是世界燃油清洁化发展的总趋势,这使得传统的加氢脱硫工艺面临着极大的挑战。光催化氧化脱硫工艺因其反应条件温和、操作成本低、可实现深度脱硫等特点,有望成为加氢脱硫的有益替代和补充工艺。本文以钛酸四丁酯为前驱物,蒙脱土作为载体,采用溶胶-凝胶法制备了钛柱撑光催化剂。借助N₂-sorption、XRD、TEM、FT-IR、UV-Vis等测试征手段对钛柱撑光催化剂进行了结构表征,考察了钛柱化剂加入量和热处理温度对钛柱撑光催化剂微观结构和活性的影响。利用自制的光催化反应器,以制备的钛柱撑材料为光催化剂,选择乙腈为萃取溶剂,以氧气为氧源,在紫外光光照下,开展了模拟汽油光催化氧化深度脱硫的实验研究,研究了钛柱撑光催化剂的光催化活性及影响光催化氧化脱硫的各个因素。结构表征结果显示,随着钛柱化剂加入量增加,钛柱撑光催化剂比表面积和孔容呈递增趋势,当Ti/CEC为72.7左右,蒙脱土层间离子交换几近饱和,此条件制备的钛柱撑光催化剂具有较大的比表面积和孔容。热处理温度是影响钛柱撑光催化剂结构和光催化性能的重要因素。350℃热处理3小时,此时钛柱撑光催化剂具有较好的光催化活性,活性组分TiO₂呈锐钛矿晶相,并且在层间分布较均匀,比表面积较合适。实验研究表明,反应时间、萃取剂用量、催化剂加入量等因素对光催化氧化脱硫有重要影响。采用鼓泡的形式引入氧气,进一步对光催化氧化脱硫工艺进行了优化研究。反应温度为25℃,光催化剂加入量为1g/L,氧气气速为800ml/min条件下反应6小时,模拟汽油硫含量由400ppm降到10ppm左右。钛柱撑光催化剂表现出非常好的光催化活性,光催化氧化脱硫工艺可以实现深度脱硫的目的。更多还原

【Abstract】 It is a great challenge for the conventional hydrodesulfurization process because it’s the trend to produce and use ultra-deep and zero emissions clean fuels. Photocatalytic oxidative desulfurization is getting more and more attention owning to its mild reactions, low operating cost and deep desulfurization.It is promising to become the substitution or compensation of hydrodesulfurization technique.Titanium pillared photocatalysts had been prepared by sol-gel method with tetrabutyl titanate as the precursor and montmorllinte as the carrier.The samples were characterized by X-ray diffraction（XRD）, Fourier transform infrared spectra（FT-IR）, transmission electron microscope（TEM）, nitrogen adsorption-desorption isotherms measurements. Factors influencing the photocatalytic properties of the samples were discussed, including the ratio of titanium pillared agent and the calcining temperature. The photocatalytic oxidative dusulfurization was conducted with the prepared photocatalyst, O2 as the oxygen resource, model gasoline and acetonitrile as the extraction solvent in the self-made photocatalytic reactor by the irradiating of ultraviolet light.and then the photocatalytic performace of the photocatalyst and factors affecting the photocatalytic desulfurization were studied.By XRD, FT-IR, TEM and nitrogen adsorption-desorption isotherms measurements, it suggests that the specific surface area and pore volume are increasing as the increasing of the titanium pillared agents. When the value of Ti/CEC is 72.7, ion capacity reaches saturation state, and under such a condition, more TiO₂ pillars added contribute little to the enlargement of distance between layers of titanium pillared montmorillonite, the photocatalyst has a higher specific surface area and pore volume. The N2 adsorption-desorption isotherms is type IV according to BDDT, attributed to the mesopore in materials with multi-peak distribution. The critical factor imfluencing the structure and performace of the photocatalyts is the calcination temperature. The titanium pillared photocatalyst appeared good photcatalytic performance and better specific surface area and under the condition of calcination at 350℃for 3 hours, and the reactivy components is anatase.The experiments of the photocatalytic oxidative desulfurization was investigated at last. The results show that the reaction time, the ratio of extraction agent, the added amount of catalysts are the important influenced factors. The optimization research was conducted further with importing the oxygen by the method of bubbling. It founded that the experiment reached a good performance under the condition of the temperature of 25℃, the added amount catalyst of 1g/L and the bubbling rate of 800ml/min. the sulfur content is reduced from 800 to about 10 ppm and it is promising to achieve the deep desulfurization by the process of photocatalytic oxidation.更多还原