The present invention relates to catalyst compositions containing a mixed oxide catalyst of formula (I) or formula (II) as described herein, their preparation, and their use in a process for ammoxidation of various organic compounds to their corresponding nitriles and to the selective catalytic oxidation of excess NH.sub.3 present in effluent gas streams to N.sub.2 and/or NO.sub.x.

A composite photocatalyst, a photocatalytic filter for air purification, and an air purification device that includes the photocatalytic filter. The composite photocatalyst includes: a first metal oxide particle; and second metal oxide particles arranged on a surface of the first metal oxide particle, wherein specific surface area of the second metal oxide particles is greater than specific surface area of the first metal oxide particle, and bandgap energy of the second metal oxide particles is greater than bandgap energy of the first metal oxide particle. The composite photocatalyst structure may degrade and remove gaseous pollutants under room temperature and atmospheric pressure conditions. The composite photocatalyst may be applied to various indoor and outdoor air purification systems in the form of a photocatalytic filter.

The present invention relates to a catalyst comprising a support substrate having a length L extending between the ends a and b, and four material zones A, B, C and D, wherein material zone B comprises bismuth.

A method of manufacturing a tubular member for an exhaust gas treatment device according to at least one embodiment of the present invention, the tubular member including a tubular main body made of a metal and an insulating layer formed on at least an inner peripheral surface of the tubular main body, the insulating layer containing glass, includes steps of: forming a coating film by bringing a coating liquid for insulating layer formation supplied to the tubular main body into contact with a contact member; and firing the coating film to obtain the insulating layer.

A composite photocatalyst, a photocatalytic filter for air purification, and an air purification device that includes the photocatalytic filter. The composite photocatalyst includes: a first metal oxide particle; and second metal oxide particles arranged on a surface of the first metal oxide particle, wherein specific surface area of the second metal oxide particles is greater than specific surface area of the first metal oxide particle, and bandgap energy of the second metal oxide particles is greater than bandgap energy of the first metal oxide particle. The composite photocatalyst structure may degrade and remove gaseous pollutants under room temperature and atmospheric pressure conditions. The composite photocatalyst may be applied to various indoor and outdoor air purification systems in the form of a photocatalytic filter.

Proposed are a low-temperature DeNOx catalyst for selective catalytic reduction having improved sulfur resistance and a method of manufacturing the same. The low-temperature DeNOx catalyst for selective catalytic reduction having improved sulfur resistance accelerates the reduction reaction of nitrogen oxides even at low temperatures despite the small amount of vanadium supported, improves sulfur poisoning resistance, does not cause secondary environmental pollution by treated gas, has excellent abrasion resistance and strength and thus the removal efficiency of nitrogen oxides is not reduced even during long-term operation, and is easy to manufacture, thus contributing to commercialization.

A method of forming a bismuth-based catalyst can include mixing an inorganic alkali compound, a bismuth source compound, a transition metal precursor, and a reducing agent in an aqueous solution to form a bismuth precursor liquid. The bismuth precursor liquid can be hydrothermally reacted at a conversion temperature for a conversion time to produce the bismuth-based catalyst.

A system and method for processing industrial waste gas based on a combination of photoelectrocatalysis and a biotrickling filter, including an industrial waste gas simulation generator, a photoelectrocatalytic reactor and at least one biotrickling filter. The industrial waste gas simulation device transports the industrial waste gas to the photoelectrocatalytic reactor through the buffer tank and the mixing tank by a fan. Then the industrial waste gas is degraded under the synergistic catalysis of the substances with high catalytic activity generated by the plasma reactor and the photocatalyst activated by the ultraviolet lamp.

A NO.sub.x absorber catalyst for treating an exhaust gas from a lean burn engine. The NO.sub.x absorber catalyst comprises a molecular sieve catalyst comprising a noble metal and a molecular sieve, wherein the molecular sieve contains the noble metal; an oxygen storage material for protecting the molecular sieve catalyst; and a substrate having an inlet end and an outlet end.

A method for preparing an SCR catalyst may include: (1) placing a first aqueous solution containing a titanium oxide and a tungstate in an electric field environment, adjusting the pH value of the first aqueous solution, and adjusting the current direction of the electric field environment to obtain a first mixture; (2) providing a second mixture by, in the electric field environment, adding dropwise a second aqueous solution containing a soluble salt of one or more active components, a copper-organic polyamine complex and a dispersant to the first mixture, and adjusting the current direction; and (3) processing the second mixture to obtain the SCR catalyst. The one or more active components may be selected from Ce, Zr, Cu, Fe, Pr and Sc.