title: The control of valence state: how V/TiO2 catalyst is hindering the deactivation using the mechanochemical method.
abstract: Various experiments were conducted to improve durability against SO(2) by impregnating the same amount of vanadium in TiO(2) which had the various physical properties. According to those catalysts, the degree of deactivation by SO(2) had various results, and it was found that the production of unreacted NH(3) in selective catalytic reduction reaction should be low. Based on X-ray photoelectron spectroscopy analysis, O(2) on-off test, O(2) reoxidation test and H(2)-temperature programmed reduction experiment, the redox capacity of catalyst was improved due to increasing of non-stoichiometric compounds. Such a non-stoichiometric oxide and redox capacity of catalyst can be enhanced by the ball-milling process, and the production of ammonium sulfate salt can be more easily inhibited by the superior oxidation-reduction capacity of catalyst. We found that this result is caused by producing and increasing of V(x+) (x<or=4), Ti(y+) (y<or=3) which are non-stoichiometric chemical species of catalyst.
authors.affiliation: Department of Chemical and Biological Engineering, Korea University, Republic of Korea.
authors.forename: Phil-Won
authors.initials: PW
authors.lastname: Seo
authors.forename: Jun-Yub
authors.initials: JY
authors.lastname: Lee
authors.forename: Kyu-Seung
authors.initials: KS
authors.lastname: Shim
authors.forename: Sung-Ho
authors.initials: SH
authors.lastname: Hong
authors.forename: Sung-Chang
authors.initials: SC
authors.lastname: Hong
authors.forename: Suk-In
authors.initials: SI
authors.lastname: Hong
mesh_terms: D000641:Ammonia; D002384:Catalysis; D010084:Oxidation-Reduction; D013458:Sulfur Dioxide; D014025:Titanium / Q000737:chemistry*; D014639:Vanadium / Q000737:chemistry*
chemical_list: D014639:Vanadium; D013458:Sulfur Dioxide; C009495:titanium dioxide; D000641:Ammonia; D014025:Titanium