Patent ID: 7820590

Claim:
A method of preparing a vanadium/titania-based catalyst for removing nitrogen oxides, comprising: (a) dissolving a vanadium precursor in an aqueous solution; (b) introducing titania into the aqueous vanadium precursor solution to form a slurry, in which the titania has a molar ratio of oxygen to titanium (O/Ti) of 1.47˜2.0 by XPS analysis and an amount of hydrogen consumed per unit weight of the titania as measured by a H 2 -TPR test is in the range of 1384 μmol/g or more; (c) removing moisture from the slurry and then drying the slurry; and (d) calcining the resulting slurry obtained in step (c) under an oxygen atmosphere to provide lattice oxygen, wherein the H 2 -TPR test is conducted under such a condition that 50 mg of the titania is heated at a heating rate of 10° C./min from room temperature to 900° C. while 5 volume % hydrogen flows through the titania at a rate of 30 cc/min and the catalyst has a generalized value for V 4+ and V 3+ of 34 atoms/cm 3 wt % or greater, and a generalized value for Ti 3+ and Ti 2+ of 415 atoms/cm 3 wt % or greater by XPS analysis, wherein the generalized value is defined as a number of non-stoichiometric atoms per unit volume (cm 3 ) of the catalyst divided by wt % of the supported vanadium.