Institute for Chemistry and Bioengineering, HCI E 127, Vladimir-Prelog-Weg 1, 8093, Zürich, Switzerland.
Paul Scherrer Institut, 5232, Villigen, Switzerland.
Angew Chem Int Ed Engl. 2016 Apr 25;55(18):5467-71. doi: 10.1002/anie.201511065. Epub 2016 Mar 24.
Direct partial oxidation of methane into methanol is a cornerstone of catalysis. The stepped conversion of methane into methanol currently involves activation at high temperature and reaction with methane at decreased temperature, which limits applicability of the technique. The first implementation of copper-containing zeolites in the production of methanol directly from methane is reported, using molecular oxygen under isothermal conditions at 200 °C. Copper-exchanged zeolite is activated with oxygen, reacts with methane, and is subsequently extracted with steam in a repeated cyclic process. Methanol yield increases with methane pressure, enabling reactivity with less reactive oxidized copper species. It is possible to produce methanol over catalysts that were inactive in prior state of the art systems. Characterization of the activated catalyst at low temperature revealed that the active sites are small clusters of copper, and not necessarily di- or tricopper sites, indicating that catalysts can be designed with greater flexibility than formerly proposed.
甲烷的直接部分氧化是催化的基石。目前，甲烷到甲醇的逐步转化涉及高温下的活化和低温下与甲烷的反应，这限制了该技术的适用性。本文首次报道了在 200°C 的等温条件下使用分子氧，由铜负载沸石直接从甲烷生产甲醇。铜交换沸石在氧气中活化，与甲烷反应，然后在重复的循环过程中用蒸汽萃取。甲醇产率随甲烷压力的增加而增加，从而使反应性与反应性较低的氧化亚铜物种相适应。在以前的技术体系中不活跃的催化剂上也可以生产甲醇。低温下对活化催化剂的表征表明，活性位是铜的小簇，而不一定是二铜或三铜位，这表明催化剂的设计可以比以前提出的更加灵活。
