Method for producing fe-doped beta zeolite catalyst monoliths

A method for producing a three-dimensional porous Fe-doped beta zeolite catalyst monolith of stacked catalyst fibers, comprising the following steps:

• a) preparing a suspension paste in a liquid aqueous diluent of Fe-doped beta zeolite particles and which suspension furthermore comprises a binder material in a maximum amount of 50 wt %, based on the amount of Fe-doped beta zeolite particles and a plasticizer and a pore-forming material, each in a maximum amount of 10 wt %, based on the amount of Fe-doped beta zeolite particles, and a peptization agent in a maximum amount of 5 wt %, based on the amount of Fe-doped beta zeolite particles, all particles in the suspension having a number average particle size in the range of from 0.05 to 700 μm,
• b) extruding the paste of step a) through one or more nozzles to form fibers, and depositing the extruded fibers to form a three-dimensional porous catalyst monolith precursor,
• c) drying the porous catalyst monolith precursor to remove the liquid diluent, and
• d) performing a temperature treatment of the dried porous catalyst monolith precursor of step c) at a temperature in the range of from 300 to 600° C., to form the Fe-doped beta zeolite catalyst monolith,
• wherein no temperature treatment of the porous catalyst monolith precursor or porous catalyst monolith at temperatures above 600° C. is performed and wherein no further catalytically active metals, catalytically active metal oxides or catalytically active metal compounds are applied to the surface of the Fe-doped beta zeolite particles, the catalyst monolith precursor or Fe-doped beta zeolite catalyst monolith, and are not present in the suspension paste, with the exception of copper, wherein in step b) the nozzles have a maximum diameter of less than 5 mm, and wherein the suspension paste in step a) contains 0 to 0.9 wt % fibers, selected from organic fibers and inorganic fibers, based on the suspension paste.