Choi Hyeonhee, Bae Jung-Hyun, Kim Do Heui, Park Young-Kwon, Jeon Jong-Ki
Department of Chemical Engineering, Kongju National University, Cheonan 331-717, Korea.
School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul 151-742, Korea.
Materials (Basel). 2013 Apr 29;6(5):1718-1729. doi: 10.3390/ma6051718.
MCM-41 was used as a support and, by using atomic layer deposition (ALD) in the liquid phase, a catalyst was prepared by consecutively loading titanium oxide and vanadium oxide to the support. This research analyzes the effect of the loading amount of vanadium oxide on the acidic characteristics and catalytic performance in the dehydration of butanol. The physical and chemical characteristics of the TiO₂-V₂O₅/MCM-41 catalysts were analyzed using XRF, BET, NH₃-TPD, XRD, Py-IR, and XPS. The dehydration reaction of butanol was performed in a fixed bed reactor. For the samples with vanadium oxide loaded to TiO₂/MCM-41 sample using the liquid phase ALD method, it was possible to increase the loading amount until the amount of vanadium oxide reached 12.1 wt %. It was confirmed that the structural properties of the mesoporous silica were retained well after titanium oxide and vanadium loading. The NH₃-TPD and Py-IR results indicated that weak acid sites were produced over the TiO₂/MCM-41 samples, which is attributed to the generation of Lewis acid sites. The highest activity of the V₂O₅(12.1)-TiO₂/MCM-41 catalyst in 2-butanol dehydration is ascribed to it having the highest number of Lewis acid sites, as well as the highest vanadium dispersion.
以MCM-41为载体,通过液相原子层沉积(ALD)法,依次将氧化钛和氧化钒负载到载体上制备催化剂。本研究分析了氧化钒负载量对丁醇脱水酸性特征和催化性能的影响。采用XRF、BET、NH₃-TPD、XRD、Py-IR和XPS对TiO₂-V₂O₅/MCM-41催化剂的物理化学特性进行了分析。丁醇脱水反应在固定床反应器中进行。对于采用液相ALD法将氧化钒负载到TiO₂/MCM-41样品上的样品,氧化钒负载量可增加至12.1 wt%。证实了负载氧化钛和氧化钒后,介孔二氧化硅的结构性能得到了很好的保留。NH₃-TPD和Py-IR结果表明,TiO₂/MCM-41样品上产生了弱酸位点,这归因于Lewis酸位点的生成。V₂O₅(12.1)-TiO₂/MCM-41催化剂在2-丁醇脱水中的最高活性归因于其具有最多的Lewis酸位点以及最高的钒分散度。