Catalytic Processes and Materials, Mesa+Institute for Nanotechnology, University of Twente, 7500AE Enschede (The Netherlands) www.utwente.nl/tnw/cpm.
ChemSusChem. 2013 Sep;6(9):1717-23. doi: 10.1002/cssc.201300445. Epub 2013 Sep 10.
Aqueous-phase reforming of ethylene glycol over alumina-supported Pt-based catalysts is reported. Performance of the catalysts is investigated by conducting kinetics and in situ attenuated total reflectance (ATR)-IR spectroscopic analysis. Pt/γ-Al2 O3 is unstable under APR conditions (270 °C, 90 bar) and undergoes phase transformation to boehmite [AlO(OH)]. This conversion of alumina is studied in situ by using ATR-IR spectroscopy; transition into boehmite proceeds even at milder conditions (210 °C, 40 bar). Pt/γ-Al2 O3 deactivates irreversibly because the Pt surface area decreases owing to an increasing metal particle size and coverage with boehmite. However, Pt supported on boehmite itself shows stable activity. Surprisingly, the rate of formation of hydrogen per Pt surface atom is significantly higher on boehmite compared to an alumina-supported catalyst. This observation seems correlated to both increased concentration of surface OH groups as well as to enhanced oxidation of Pt when comparing Pt/γ-Al2 O3 with Pt/AlO(OH).
报道了乙二醇在氧化铝负载的铂基催化剂上的水相重整反应。通过动力学和原位衰减全反射（ATR）-IR 光谱分析研究了催化剂的性能。Pt/γ-Al2 O3 在 APR 条件（270°C，90 巴）下不稳定，会发生向勃姆石[AlO(OH)]的相转变。通过使用 ATR-IR 光谱原位研究了氧化铝的这种转化；即使在较温和的条件（210°C，40 巴）下也会发生向勃姆石的转化。由于金属颗粒尺寸增大和被勃姆石覆盖，Pt/γ-Al2 O3 不可逆失活，导致 Pt 表面积减小。然而，负载在勃姆石上的 Pt 表现出稳定的活性。令人惊讶的是，与负载在氧化铝上的催化剂相比，每 Pt 表面原子形成的氢气的速率在勃姆石上显著更高。这一观察结果似乎与表面 OH 基团的浓度增加以及 Pt 的氧化增强有关，当将 Pt/γ-Al2 O3 与 Pt/AlO(OH)进行比较时。
