An oxidation catalyst for treating an exhaust gas produced by a diesel engine comprises a catalytic region and a substrate, wherein the catalytic region comprises a catalytic material comprising: bismuth (Bi) or an oxide thereof; a Group 8 metal or an oxide thereof; a platinum group metal (PGM) selected from the group consisting of (i) platinum (Pt), (ii) palladium (Pd) and (iii) platinum (Pt) and palladium (Pd); and a support material, which comprises alumina, silica, a mixed oxide of alumina and a refractory oxide, a mixed oxide of silica and a refractory oxide, a composite oxide of alumina and a refractory oxide, a composite oxide of silica and a refractory oxide, alumina doped with a refractory oxide or silica doped with a refractory oxide.

Use of a ternary vanadate of formula (I): Fe.sub.x MeI.sub.y MeII.sub.z VO.sub.4 wherein MeI and MeII are different from each other and each stand for an element selected from the group consisting of Y, La, Ce, Pr, Nd, Sm, Er, Gd, Tb, Dy, Ho, Tm, Yb, Lu, Al, Bi and Sb and wherein x=0.05-0.9; y=0.05-0.9; z=0.05-0.9; x+y+z=1, as a catalyst for the oxidation of carbonaceous compounds in combustion engines.

An oxidation catalyst is described for treating an exhaust gas produced by a diesel engine comprising a catalytic region and a substrate, wherein the catalytic region comprises a catalytic material comprising: bismuth (Bi) or an oxide thereof; an alkali metal or an oxide thereof; a platinum group metal (PGM) selected from the group consisting of (i) platinum (Pt), (ii) palladium (Pd) and (iii) platinum (Pt) and palladium (Pd); and a support material comprising a mixed oxide of alumina and silica, a mixed oxide of silica and a refractory oxide, a composite oxide of alumina and silica, a composite oxide of silica and a refractory oxide, alumina doped with a silica or silica doped with a refractory oxide.

A photocatalyst includes a composite fiber having at least two crystalline semi-conductors that provide a heterojunction structure in the composite fiber.

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 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.

Object and purpose are to provide an exhaust gas purification catalyst capable of efficiently removing a nitrogen oxide in a relatively low-temperature exhaust gas discharged from a marine diesel engine or the like using a reducing agent in a smaller amount than in the past. An exhaust gas purification catalyst is used in a combustion exhaust gas purification method for removing a nitrogen oxide in a combustion exhaust gas by reducing the nitrogen oxide to nitrogen, wherein an alcohol is added to the combustion exhaust gas as a reducing agent for reducing the nitrogen oxide, and is characterized in that the catalyst is composed of a support and a denitration catalytic metal supported on the support, and the support is a zeolite having a value (S) obtained by dividing a peak area (A) in an AlOH spectrum measured with a Fourier transform infrared spectrometer (FT-IR) by a measurement support weight (W) of 1500 to 3500.

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.

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.

An electrocatalytic device for carbon dioxide conversion includes a cathode with a Catalytically Active Elementa metal in the form of supported or unsupported particles or flakes with an average size between 0.6 nm and 100 nm. The reaction products comprise at least one of CO, HCO.sup., H.sub.2CO, (HCOO).sup., HCOOH, CH.sub.3OH, CH.sub.4, C.sub.2H.sub.4, CH.sub.3CH.sub.2OH, CH.sub.3COO.sup., CH.sub.3COOH, C.sub.2H.sub.6, (COOH).sub.2, (COO.sup.).sub.2, and CF.sub.3COOH.