A urea water solution injection system includes a urea water solution injection device for spraying a urea water solution into a portion of an exhaust passageway upstream of a selective catalytic reduction catalyst device, to reduce NOx in exhaust gas discharged from an internal combustion engine. Engine coolant is circulated through the urea water solution injection device to prevent freezing of the urea water solution. A crystal dissolution control unit performs crystal dissolution control on the urea water solution injection device by energizing at a preset amount of energization at a state where a urea water solution supply pump for supplying a urea water solution to the urea water solution injection device is kept stopped, and the crystal dissolution control unit performs the crystal dissolution control for a crystal dissolving energization time calculated in advance, after the engine is started but before a urea water solution is supplied.

STA-20, a molecular sieve having a new framework type, is described. STA-20AP (as prepared) can have an alkyl amine, such as trimethylamine, and 1,6-(1,4-diazabicyclo[2.2.2]octane) hexyl cations (from diDABCO-C6) as SDAs. A lower alkyl ammonium hydroxide, such as tetrabutylammonium hydroxide, can be used as a pH modifier for making SAPO STA-20. A calcined product, STA-20C, formed from as made STA-20 is also described. Methods of preparing STA-20, activating STA-20 by calcination, and metal containing calcined counterparts of STA-20 are described along with methods of using STA-20 and metal containing calcined counterparts of STA-20 in a variety of processes, such as treating exhaust gases and converting methanol to olefins are described.

An exhaust system for an internal combustion engine, the exhaust system comprising, a lean NO.sub.x trap, and a wall flow monolithic substrate having a pre-coated porosity of 40% or greater, and comprising an oxidation catalytic zone, the oxidation catalytic zone comprising a platinum group metal loaded on a first support, the first support comprising at least one inorganic oxide and a zinc compound.

Provided is a system for treating a flowing exhaust gas comprising a lean NOx trap, a catalyzed soot filter, an ammonia or an ammonia precursor metering system for metering ammonia or an ammonia precursor into the flowing exhaust gas; and an SCR catalyst, wherein the SCR catalyst is disposed downstream of the lean NOx trap and comprises copper and/or iron supported on a small pore molecular sieve.

Described are catalyst materials and catalytic articles comprising a metal exchanged SAPO material comprising a plurality of substitutional sites consisting essentially of Si(4Al) sites and substantially free of Si(0Al) sites. The materials and catalytic articles are useful in methods and systems to catalyze the reduction of nitrogen oxides in the presence of a reductant.

The present invention provide a method for purifying exhaust gas in which nitrogen oxides (NOx) gas is removed from a combustion exhaust gas. The method for purifying exhaust gas according to the invention is characterized in that water vapor is further added to raw exhaust gas to be processed to increase the water vapor concentration in the exhaust gas and the resulting moisture-adjusted exhaust gas is introduced into a denitration catalyst layer. The water vapor concentration in the moisture-adjusted exhaust gas is preferably 22.0% by volume or less in the total of the water vapor originally contained in the raw exhaust gas and the added water vapor.

A method for production of vanadium catalysts, including steps of 1) providing a mixture comprising a TiO.sub.2-based support and a composite oxide containing vanadium and antimony; 2) preparing a slurry containing the mixture obtained from step 1), and additive comprising at least one species selected from the group consisting of Si, Al, Zr, Ti, W and Mo, and a solvent; and 3) applying the slurry onto a substrate or processing the slurry into shaped bodies. The vanadium catalysts obtained/obtainable from the method, and use thereof for abatement of nitrogen oxides (NOx).

A mixing assembly for an exhaust aftertreatment system includes: a mixing body including upstream and downstream mixing body openings, the upstream mixing body opening configured to receive exhaust gas; an upstream plate coupled to the mixing body, the upstream plate including a plurality of upstream plate openings, each of the plurality of upstream plate openings configured to receive a flow percentage that is less than 50% of a total flow of the exhaust gas; a downstream plate coupled to the mixing body downstream from the upstream plate in a direction of exhaust gas flow, the downstream plate including a downstream plate opening; and a swirl plate positioned between the upstream plate and the downstream plate and defining a swirl collection region and a swirl concentration region, the swirl collection region positioned over the plurality of upstream plate openings and the swirl collection region positioned over the downstream plate opening.

A method of coating a substrate with a foam is described. The method comprises: (a) introducing a foam into a substrate comprising a plurality of channels through open ends of the channels at a first end of the substrate; and (b) applying at least one of (i) a vacuum to open ends of the channels at a second end of the substrate and (ii) a pressure to the open ends of the channels at the first end of the substrate; wherein the foam comprises a particulate material, and wherein the foam is particle stabilized.

STA-18, a molecular sieve having a SFW structure and containing phosphorus in the framework, is described. STA-18AP (as prepared) can have a lower alkyl amine, such as trimethylamine, and one of 1,6-(1,4-diazabicyclo[2.2.2]octane)hexyl cations (from diDABCO-C6) or 1,7-(1,4-diazabicyclo[2.2.2]octane)heptyl cations (from diDABCO-C7) or 1,8-(1,4-diazabicyclo[2.2.2]octane)octyl cations (from diDABCO-C8) as SDAs. A lower alkyl ammonium hydroxide, such as tetrabutylammonium hydroxide, can be used as a pH modifier for making SAPO STA-18. A calcined product, STA-18C, formed from STA-18AP is also described. Methods of preparing STA-18AP, STA-18C and metal containing calcined counterparts of STA-18C are described along with methods of using STA-18C and metal containing calcined counterparts of STA-18C in a variety of processes, such as treating exhaust gases and converting methanol to olefins are described.