Influence of the metallic and acidic component modification on the activity of bifunctional catalysts for one-step DME synthesis from syngas

Introduction Dimethyl ether (DME) is one of the most promising benign fuel. It can be used as a diesel substitute due to high cetane number. Because of its low auto-ignition temperature, high oxygen content and absence of C-C bond in molecular structure it undergoes almost smoke-free combustion. Those properties and the variety of possible applications caused an increasing interest in DME [1, 2]. There are two possible chemical routes for synthesis of DME. One, in which two separates reactions occur, is called indirect synthesis of DME. Another strategy is the direct synthesis of DME from synthesis gas combining CO hydrogenation to methanol and the following dehydration to DME in a single step called syngas to DME (STD). The main advantage of the STD process over conventional two-step DME synthesis is that it is more thermodynamically favorable. Thus, during the STD process, the yield of DME is improved and syngas conversion is higher. For that reason, the production cost of DME in STD process is lower than in traditional DME synthesis [3].