Abstract
The methanol-to-hydrocarbon (MTH) reaction has received considerable attention as utilizing renewable sources of both value-added chemicals and fuels becomes a number one priority for society. Here, for the first time we report the development of hierarchical zeolites (ZSM-5) containing both iron oxide and nickel oxide nanoparticles. By modifying the iron oxide (magnetite, Fe3O4) amounts, we are able to control the catalyst activity and the product distribution in the MTH process. At the medium Fe3O4 loading, the major fraction is composed of C-9-C-11 hydrocarbons (gasoline fraction). At the higher Fe3O4 loading, C-1-C-4 hydrocarbons prevail in the reaction mixture, while at the lowest magnetite loading the major component is the C-5-C-8 hydrocarbons. Addition of Ni species to Fe3O4-ZSM-5 leads to the formation of mixed Ni oxides (NiO/Ni2O3) positioned either on top of or next to Fe3O4 nanoparticles. This modification allowed us to significantly improve the catalyst stability due to diminishing coke formation and disordering of the coke formed. The incorporation of Ni oxide species also leads to a higher catalyst activity (up to 9.3 g(methanol)/(g(ZSM-5) x h)) and an improved selectivity (11.3% of the C-5-C-8 hydrocarbons and 23.6% of the C-9-C-11 hydrocarbons), making these zeolites highly promising for industrial applications.