Provided is a combustion system using a catalyst having better denitration efficiency at low temperatures, during a selective catalytic reduction reaction in which ammonia is used as a reducing agent.

This combustion system comprises: a combustion device that combusts fuel; an exhaust path through which flows exhaust gas generated from the combustion of fuel in the combustion device; a dust collection device that is arranged on the exhaust path and collects soot/dust in the exhaust gas; and a denitration device that is arranged on the exhaust path and removes nitrogen oxides from the exhaust gas by means of a denitration catalyst, wherein the denitration device is arranged downstream of the dust collection device on the exhaust path, and the denitration catalyst contains vanadium oxide, has a carbon content of 0.05 wt % or more, and has a defect site in which oxygen deficiency occurs in a crystal structure.

Provided is a combustion system using a catalyst having better denitration efficiency at low temperatures, during a selective catalytic reduction reaction in which ammonia is used as a reducing agent.

This combustion system comprises: a combustion device that combusts fuel; an exhaust path through which flows exhaust gas generated from the combustion of fuel in the combustion device; a dust collection device that is arranged on the exhaust path and collects soot/dust in the exhaust gas; and a denitration device that is arranged on the exhaust path and removes nitrogen oxides from the exhaust gas by means of a denitration catalyst, wherein the denitration device is arranged downstream of the dust collection device on the exhaust path, and the denitration catalyst contains vanadium oxide, has a carbon content of 0.05 wt % or more, and has a defect site in which oxygen deficiency occurs in a crystal structure.

Provided is a titanium oxide fine particle mixture having a high photocatalytic activity, especially a high photocatalytic activity in the visible light region. The titanium oxide fine particle mixture contains: first titanium oxide fine particles; and second titanium oxide fine particles, wherein the second titanium oxide fine particles are titanium oxide fine particles with at least an iron component and a silicon component solid-dissolved therein, and the first titanium oxide fine particles are titanium oxide fine particles that may have a component(s) other than an iron component and a silicon component solid-dissolved therein.

Proposed are a low-temperature de-NOx catalyst for treating exhaust gas from a stationary source and a method of manufacturing the same. The low-temperature de-NOx catalyst can promote the reduction reaction of nitrogen oxide even at a low temperature despite supporting vanadium in a small amount, can increase resistance to sulfur poisoning, and can be easily manufactured in a manner that does not deteriorate nitrogen oxide removal efficiency even after long-term operation because it prevents secondary environmental pollution due to the treated gas and has superior abrasion resistance, thereby contributing to commercialization.

Proposed are a low-temperature de-NOx catalyst for treating exhaust gas from a stationary source and a method of manufacturing the same. The low-temperature de-NOx catalyst can promote the reduction reaction of nitrogen oxide even at a low temperature despite supporting vanadium in a small amount, can increase resistance to sulfur poisoning, and can be easily manufactured in a manner that does not deteriorate nitrogen oxide removal efficiency even after long-term operation because it prevents secondary environmental pollution due to the treated gas and has superior abrasion resistance, thereby contributing to commercialization.

The present invention provides a catalyst module for removing harmful gas, wherein an oxidation reaction or reduction reaction of harmful gas is carried out in a self-heating heating carrier. According to an embodiment of the present invention, the catalyst module for removing harmful gas comprises: a heating carrier composed of an electrically heatable heating body, including one or more flow channels inside, and having a porous structure with pores; and a catalyst region formed on at least a portion of the surface of the heating carrier including the flow channels and containing a catalyst material for promoting a decomposition reaction of harmful gas passing through the flow channels, wherein the catalyst region comprises: a first catalyst layer having a first catalyst material loading amount in the pores of the heating carrier; and a second catalyst layer applied on the inner surface of the heating carrier.

Provided in this disclosure are oxidative dehydrogenation catalysts that include a mixed metal oxide having the empirical formula:
Mo.sub.1.0V.sub.0.12-0.49Te.sub.0.05-0.17Nb.sub.0.10-0.20O.sub.d
wherein d is a number to satisfy the valence of the oxide. The oxidative dehydrogenation catalyst is characterized by having XRD diffraction peaks (2θ degrees) at 22±0.2, 27±0.2, 28.0±0.2, and 28.3±0.1. The disclosure also provides methods of making the catalysts that include wet ball milling.

Provided in this disclosure are oxidative dehydrogenation catalysts that include a mixed metal oxide having the empirical formula:
Mo.sub.1.0V.sub.0.12-0.49Te.sub.0.05-0.17Nb.sub.0.10-0.20O.sub.d
wherein d is a number to satisfy the valence of the oxide. The oxidative dehydrogenation catalyst is characterized by having XRD diffraction peaks (2θ degrees) at 22±0.2, 27±0.2, 28.0±0.2, and 28.3±0.1. The disclosure also provides methods of making the catalysts that include wet ball milling.

Provided are a selective reducing catalyst for diesels and a diesel exhaust gas purification apparatus in which deterioration of NO.sub.x removal performance due to phosphorus poisoning is less likely to occur.

The selective reducing catalyst for diesels is arranged in a diesel engine, adsorbs ammonia and brings the ammonia into contact with nitrogen oxides in an exhaust gas discharged from a diesel engine to perform reduction, the selective reducing catalyst comprises: a catalyst carrier; a catalyst region provided on at least the catalyst carrier; and a phosphorus trapping region provided on at least the catalyst region, wherein the catalyst region comprises one or more selected from the group consisting of a zeolite-based catalyst containing at least zeolite and a transition metal element supported on the zeolite, a W—Ce—Zr composite oxide-based catalyst, and a vanadium-based catalyst, and the phosphorus trapping region comprises at least one or more selected from the group consisting of alumina and a rare earth-based basic oxide.

Provided are a denitration catalyst regeneration method and a denitration catalyst regeneration system, which are capable of recovering denitration performance to a high level and reducing the SO.sub.2 oxidation rate of a catalyst. A denitration catalyst regeneration method according to the present invention includes: a chemical solution cleaning step for immersing a denitration catalyst in a chemical solution containing a fluorine compound and an inorganic acid; a step for extracting the denitration catalyst from the chemical solution; and a finish washing step for washing the denitration catalyst extracted from the chemical solution with a finish cleaning solution containing an organic acid.