EXTRUDED HONEYCOMB CATALYST
Disclosed are an extruded honeycomb catalyst, a process for preparing the catalyst, a method for reducing NOx in the exhaust gas from an internal combustion engine by using the catalyst, and a method for treatment of the emission gas generated from power plant comprising exposing the emission gas to the catalyst.
1 - 24 . (canceled)
25 . A process for preparing a catalyst, the method comprising:
i) mixing the vanadium oxide and/or a precursor thereof, the antimony oxide and/or a precursor thereof, or the mixed antimony and vanadium oxide, or the mixed iron and vanadium oxide, optionally a support and/or a precursor thereof, and optionally a binder and/or matrix and/or a precursors thereof into a shapeable mixture;
ii) extruding the shapeable mixture into a flow-through honeycomb catalyst body;
iii) drying the catalyst body; and
iv) calcining the catalyst body.
26 . The process according to claim 25 , comprising:
providing a solution or a mixture comprising the vanadium oxide and/or the precursors thereof, the antimony oxide and/or the precursors thereof, or the mixed antimony and vanadium oxide, or the mixed iron and vanadium oxide, the optional support and/or the precursors of, and the optional binder and/or matrix and the precursors thereof, and mixing the solution or the mixture to obtain the shapeable mixture;
extruding the shapeable mixture into the flow-through honeycomb catalyst body with continuous channels and with a six-edge cross section exhibiting a cell density of 200 cells per square inch;
wrapping the catalyst body in foil and drying it in air for 6 weeks or freeze drying at a temperature of −10° C. to −30° C. at low pressure; and
calcining at a temperature of 600° C. for 1 to 6 hours to form a solid catalyst body.
27 . The process according to claim 25 , wherein the precursor of the vanadium oxide is used and the precursor of the vanadium oxide is chosen from ammonium vanadate, vanadyl oxalate, vanadium pentoxide, vanadium monoethanolamine, vanadium chloride, vanadium trichloride oxide, vanadyl sulfate and vanadium antimonate.
28 . The process according to claim 25 , wherein the precursor of the antimony oxide is used and the precursor of the antimony oxide is chosen from antimony acetate, ethylene glycol antimony, antimony sulfate, antimony nitrate, antimony chloride, antimonous sulfide, antimony oxide and antimony vanadate.
29 . The process according to claim 25 , wherein in the mixing i) a solvent comprising water is added and/or a pore forming agent is added.
30 . The process according to claim 25 , wherein in the mixing i) one or more conventional additives of plasticizer, dispersant, and precipitator are added.
31 . A method for reducing NOx in an exhaust gas from an internal combustion engine, the method comprising contacting the exhaust gas with a catalyst prepared according to claim 25 in the presence of a reductant.
32 . The method according to claim 31 , wherein the exhaust gas is contacted with the catalyst under a temperature in the range of 150° C. to 650° C., 180° C. to 600° C., or 200° C. to 550° C.
33 . The method according to claim 31 , wherein the internal combustion engine is a diesel engine.
34 . A method for treating an emission gas generated from power plant, the method comprising exposing the emission gas to a catalyst prepared according to claim 25 .