Ágnes Szécsényi

DSC 0281~2~2


Van der Maasweg 9, 2629 HZ Delft 
Room E2.360

Tel:  *31 (0)15 2786955

e-mail: A.Szecsenyi@tudelft.nl




Computation study of catalytic methane activation

Currently oil derived hydrocarbons are the most important source for energy and chemicals. However their amount is finite, they might be sufficient for a few more decades. Until humanity finds a sustainable way to satisfy the energy demand they need to be used efficiently. Natural gas, the most abundant hydrocarbon source mainly consists of methane. 

At room temperature methane is a highly flammable gas, it is needed to be compressed before transportation, which makes it expensive. Currently natural gas that is a side product of oil exploitation at remote areas is being burnt, and natural gas reservoirs located at deserted places are not exploited. Converting natural gas to liquid at the place of the exploitation is an attractive solution for the costly transportation. A desirable candidate is methanol, a compound with a high energy density per volume. An existing technology for methane conversion is a two-step process through synthesis gas. Due to the huge energy demand of the first conversion step the development of a low-temperature one-step catalytic process is desirable. A technical economic assessment showed that the direct process for methanol production could compete with the conventional indirect technology in terms of production costs if an 80% selectivity of methanol could be achieved at a single pass methane conversion of 10%. [1]

Due to the fact that the C-H bond in methane is stronger than in methanol the direct methane to methanol process is particularly challenging. It favours the overoxidation of methanol to other oxygenated hydrocarbons and carbon oxides. In fact, research on this topic has been going on for more than a hundred years [2]. It was discovered that nature is able to carry out this process, methane mono-oxygenase enzymes convert methane to methanol very efficiently. These enzymes have well-defined active centres containing either diiron or dicopper complexes. As an attempt to mimic nature scientists have tried to incorporate these species into different catalysts. Many organic and inorganic frameworks has been tried to host these active sites. Among them zeolites have gotten a lot of attention recently. Iron and copper containing zeolites have the remarkable ability to convert methane to oxygenated hydrocarbons with high selectivity [3, 4]. Another group of novel materials that might be suitable for selective methane oxidation are metal organic framework. Their chemical and physical properties can be modified and tuned by the nature of the reactants and the process in a broad range.

The aim of this project is to study the reaction mechanism of methane oxidation in zeolites and other materials in order to understand the limitations of the current processes by using computational tools. Addressing mechanistic details on selective methane oxidation aims to complement experimental research.

  1. Recent progress in direct partial oxidation of methane to methanol; Q. Zhang, D. He and Q. Zhu; Journal of Natural Gas Chemistry, 12, 81-89. (2003)
  2. The slow oxidation of methane at low temperatures; W. A. Bone and R. V. Wheeler; J. Chem Soc., 81, 535 (1902).
  3. Quasicatalytic and catalytic oxidation of methane to methanol by nitrous oxide over FeZSM-5 zeolite; M. V. Parfenov, E. V. Starokon, L. V. Pirutko, G. I. Panov; J. Catal., 318, 14–21. (2014)
  4. Elucidation and evolution of the active component within Cu/Fe/ZSM-5 for catalytic methane oxidation: From synthesis to catalysis; C. Hammond, N. Dimitratos, R. L. Jenkins, J. A. Lopez-Sanchez, S. A. Kondrat, M. Hasbi ab Rahim, M. M. Forde, A. Thetford, S. H. Taylor, H. Hagen, E. E. Stangland, J. H. Kang, J. M. Moulijn, D. J. Willock, and G. J. Hutchings; ACS Catalysis 3 (4), 689-699. (2013)


Acknowledgements 

This research receives funding from the Dutch National Science Foundation (NWO-CW) / VIDI Grant Agreement n. 723.012.107, MetMOFCat. The supercomputer facilities are supported by SurfSARA and NWO.