After its discovery by Mobil in the 70s, the conversion of MeOH to hydrocarbons (MTH) has attracted significant attention (see also figure 1). Starting from a flexible carbon feedstock such as natural gas, coal, or biomass, basic petrochemicals and fuels can be efficiently obtained. The product spectrum is heavily dependent on several parameters, such as the microstructure of the zeolitic catalyst and its acidity, as well as the temperature and pressure of the process, the reactant concentration in the feed and the contact time.
Using zeolites with narrow channels as catalysts (such as SAPO 34), lower olefins are produced with high selectivity, but the lifetime of the catalyst is short due to blocking of the channels by the heavier products. On the other hand, ZSM-5 with wider channels has a much longer lifetime but generates a complex mixture of linear and branched olefins and paraffins as well as substituted benzenes.
Depending on the desired product spectrum the research activities are dedicated to formation of aromatics (methanol-to-aromatics =MTA), the formation of gasoline (methanol-to-gasoline=MTG) or the formation of olefins (methanol-to-olefins=MTO).
The short lifetime of the catalysts is currently the biggest challenge. Due to the fast deactivation, analysis methods must be precise and yield a sufficient time resolution. A solution for this challenge are fast online analysis tools based on gas chromatography or spectroscopy as well as short contact time experiments using fluidized bed or entrained flow concepts. Although, the previously mentioned ZSM-5 and SAPO-34 are promising materials, other catalysts might be of interest with less deactivating behavior.
hte offers various services in the field of methanol utilization:
- Preparation and testing of novel material compositions
- Detailed analysis of complex hydrocarbon product mixtures, supported by hte’s data management workflows
- Characterization of fast deactivating catalyst systems, including the study of catalyst regeneration protocols
- Ranking of commercial catalyst system with regards to activity, selectivity, contact time, and life time
- Evaluation of short-lived catalysts using fluidized bed experiments
Unni Olsbye, Stian Svelle, Morten Bjørgen, Pablo Beato, Ton V.W. Janssens, Finn Joensen, Silvia Bordiga, Karl Petter Lillerud,
“Conversion of methanol to hydrocarbons: how zeolite cavity and pore size controls product selectivity”
Angew. Chem. Int. Ed., 2012, 51, 5810 – 5831. DOI.
Jerzy Szczygieł, Marek Kułażyński,
“Thermodynamic limitations of synthetic fuel production using carbon dioxide: A cleaner methanol-to-gasoline process”
Journal of Cleaner Production, 2021, 276, 122790. DOI.
Peng Tian, Yingxu Wei, Mao Ye, Zhongmin Liu,
“Methanol to Oleﬁns (MTO): From Fundamentals to Commercialization”
ACS Catal., 2015, 5, 1922–1938. DOI.