A catalyst bed comprising a ceramic or metallic foam comprising one or more NO.sub.x reduction catalysts is described. A method for reducing the concentration of NO.sub.x in a dust containing gas stream comprising: a) passing a first gas stream containing NO.sub.x into a contacting zone; b) contacting the first gas stream with a ceramic or metallic foam catalyst bed having one or more flow paths through the catalyst bed wherein the ceramic or metallic foam comprises a NO.sub.x reduction catalyst to produce a second gas stream with a reduced NO.sub.x concentration; and c) passing the second gas stream out of the contacting zone wherein the first gas stream has a dust concentration of at least 5 mg/Nm.sup.3 and the pressure drop of the foam catalyst bed increases by 300% or less relative to the initial pressure drop of the foam catalyst bed due to dust accumulation, measured under the same conditions is also described.

A catalyst bed comprising a ceramic or metallic foam comprising one or more NO.sub.x reduction catalysts is described. A method for reducing the concentration of NO.sub.x in a dust containing gas stream comprising: a) passing a first gas stream containing NO.sub.x into a contacting zone; b) contacting the first gas stream with a ceramic or metallic foam catalyst bed having one or more flow paths through the catalyst bed wherein the ceramic or metallic foam comprises a NO.sub.x reduction catalyst to produce a second gas stream with a reduced NO.sub.x concentration; and c) passing the second gas stream out of the contacting zone wherein the first gas stream has a dust concentration of at least 5 mg/Nm.sup.3 and the pressure drop of the foam catalyst bed increases by 300% or less relative to the initial pressure drop of the foam catalyst bed due to dust accumulation, measured under the same conditions is also described.

A method for producing dicarboxylic acid. The method includes: subjecting a raw material system including a cyclic olefin and a lower monocarboxylic acid to an addition reaction in the presence of an addition reaction catalyst to generate an intermediate product system including cyclic carboxylic acid ester; and subjecting the intermediate product system including cyclic carboxylic acid ester to a ring-opening and oxidation reaction in the presence of an oxidant and an oxidation catalyst to generate a corresponding dicarboxylic acid product. The addition reaction in the dicarboxylic acid synthesis route achieves a high single-pass conversion rate, and the selectivity of the corresponding cyclic carboxylic acid ester is high. The addition-oxidation synthesis route achieves faster reaction rates for both the addition reaction and oxidation reaction, and high yield of corresponding dicarboxylic acid product. The addition-oxidation based synthesis route is suitable for continuous, stable and large-scale production of corresponding dicarboxylic acid product.

A method for producing dicarboxylic acid. The method includes: subjecting a raw material system including a cyclic olefin and a lower monocarboxylic acid to an addition reaction in the presence of an addition reaction catalyst to generate an intermediate product system including cyclic carboxylic acid ester; and subjecting the intermediate product system including cyclic carboxylic acid ester to a ring-opening and oxidation reaction in the presence of an oxidant and an oxidation catalyst to generate a corresponding dicarboxylic acid product. The addition reaction in the dicarboxylic acid synthesis route achieves a high single-pass conversion rate, and the selectivity of the corresponding cyclic carboxylic acid ester is high. The addition-oxidation synthesis route achieves faster reaction rates for both the addition reaction and oxidation reaction, and high yield of corresponding dicarboxylic acid product. The addition-oxidation based synthesis route is suitable for continuous, stable and large-scale production of corresponding dicarboxylic acid product.

The present invention is directed towards the use of an ion-exchanged zeolite containing ASC as a trap for volatile vanadium compounds in a downstream position of a vanadium containing SCR-catalyst.

The present invention is directed towards the use of an ion-exchanged zeolite containing ASC as a trap for volatile vanadium compounds in a downstream position of a vanadium containing SCR-catalyst.

The invention relates to an installation and a method for treating hydrogen sulphide. In particular, the invention relates to an installation and a method comprising at least one system for oxidizing hydrogen sulfide to sulfur (S) and water (H.sub.2O) with a solid reagent and at least one oxidizing system with an agent for oxidizing the solid reagent present in the reduced state, wherein the system of oxidizing the hydrogen sulfide to sulfur and the system for oxidizing the solid reagent, are so arranged that the hydrogen sulfide is not brought into contact with the agent oxidizing the solid reagent.

The invention relates to an installation and a method for treating hydrogen sulphide. In particular, the invention relates to an installation and a method comprising at least one system for oxidizing hydrogen sulfide to sulfur (S) and water (H.sub.2O) with a solid reagent and at least one oxidizing system with an agent for oxidizing the solid reagent present in the reduced state, wherein the system of oxidizing the hydrogen sulfide to sulfur and the system for oxidizing the solid reagent, are so arranged that the hydrogen sulfide is not brought into contact with the agent oxidizing the solid reagent.

The present invention relates to a method for preventing an SCR catalyst from being contaminated with platinum group metal in an emission control system comprising, upstream of the SCR catalyst, a catalyst that contains platinum group metal, characterized in that a material zone containing a mixture of aluminum oxide and cerium oxide is located upstream of the SCR catalyst.

Provided is a method of preparing an intermetallic catalyst which includes applying ultrasonic wave to a precursor mixture solution including a noble metal precursor, a transition metal precursor, and a carbon support having an average pore size of about 6 nm to about 15 nm and a specific surface area of about 200 m.sup.2/g to about 2000 m.sup.2/g to form alloy particles in pores of the carbon support, and annealing the alloy particles in the pores of the carbon support to form intermetallic alloy particles.