Ti-USY光催化氧化脱除汽油中含硫化合物的研究

Study of desulfuration activities of gasoline by photocatalytic oxidation method using Ti-USY

以钛酸四正丁酯为钛源,浸渍法制备了Ti-USY分子筛光催化剂,对光催化氧化汽油脱硫工艺条件(催化剂的加入量、氧化剂H2O2的用量、反应温度、萃取剂)、催化剂再生性和二次重复使用的稳定性进行考察。结果表明,Ti O2高度分散在USY分子筛表面上,催化剂样品均为典型的Ⅳ型吸附等温线,孔分布较窄。在催化剂的加入量为2 g/L,反应温度为40℃,水作为萃取剂,水油体积比为1∶1,1.5 h光照反应条件下,FCC汽油的脱硫率可达到62.4%。Ti-USY催化剂经7次高温再生后,脱硫率下降较小,仍在58%以上。2次重复使用脱硫率为42.66%。证明Ti-USY分子筛光催化剂良好的催化性能、再生性及稳定性。动力学分析表明,Ti-USY分子筛对汽油硫化物的光催化氧化动力学遵循标准一级反应,表观活化能为9.046 k J/mol。

Ti-USY zeolite photocatalys were successfully synthesized by impregnation method using the ti-tanium-butoxide（ TB）as titanium source. Study the photocatalytic oxidation desulfurization performance by using FCC gasoline as the raw material under UV light irradiation. The effects of the amount of cata-lyst,the amount of oxidant H2 O2 ,the reaction temperature,the extraction solvent,the regeneration and the secondary reuse stability of catalyst were investigated. Results showed that TiO2 dispers well on the surface USY. Samples are typical Ⅳ type adsorption isotherm and narrow pore size distribution. Under suitable conditions：the amount of catalyst was added at 2 g/L,the reaction temperature was 40℃,water as extrac-ting agent is selected,the volume ratio of water to oil is 1：1,illumination time is 1. 5 h. FCC gasoline des-ulfurization rate can reach 62 . 4%. After the Ti-USY catalyst were high-temperature regenerated by 7 times or was repeated using by 2 times,the desulfurization rate decreased less,still more than 58%and 42. 66%. Ti-USY zeolite catalytic has good performance in photocatalyst,reproducibility and stability. Ki-netic analysis showed that reaction kinetics of Ti-USY zeolite photocatalytic oxidation gasoline desulfura-tion is first-order,apparent activation energy is 9. 046 kJ/mol.