A catalyst for treating an exhaust gas comprising SO.sub.2, NO.sub.x and elemental mercury in the presence of a nitrogenous reductant comprises a composition containing oxides of: (i) Molybdenum (Mo) and optionally Tungsten (W); and (ii) Vanadium (V); and (iii) Titanium (Ti); and (iv) Phosphorus (P), wherein, with respect to the total metal atoms in the composition, the composition comprises: (i) Mo in an amount of less than 2 at. %, and optionally up to 9 at. % W; (ii) from 2.5 to 12 at. % V; (iii) from 85 to 96 at. % Ti, and wherein the composition comprises (iv) P in an atomic ratio to the sum of atoms of Mo, W and V of from 1:2 to 3:2. The values expressed must total 100%.

An exhaust aftertreatment system for use with an automotive diesel engine, the system includes a selective catalytic reduction unit a reagent storage tank, and a reagent distribution system. A reagent fluid is stored in the reagent storage tank. The reagent is delivered to exhaust gases produced by the engine using the reagent distributor. The selective catalytic reduction unit is positioned downstream of the reagent distributor and is configured to remove effluents from the exhaust gases.

The present invention relates to processes employing water produced from wells that, after suitable purification steps, is processed to recover resources that can be used to treat other waste streams, such as flue gases and ashes from combustion of fossil fuels.

An as-synthesized microporous material having a CHA structure and containing at least one organic structure directing agent that has the following general structure of the quaternary ammonium cation is disclosed:

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A microporous crystalline material made from the as-synthesized material is also disclosed. A method of making microporous crystalline material using one or more organic structure directing agents is also disclosed. A method of selective catalytic reduction of nitrogen oxides in exhaust gas that comprises contacting exhaust gases, typically in the presence of ammonia, urea, an ammonia generating compound, or a hydrocarbon compound, with an article comprising the disclosed microporous crystalline is also disclosed.

A combustion system operated at low cost is provided. A combustion system 1 includes a combustion device 10 that burns fuel, an exhaust line L1 through which exhaust gas flows, the exhaust gas being generated through combustion of the fuel in the combustion device 10, an air preheater 30 that is disposed in the exhaust line L1 and that recovers heat from the exhaust gas, and a denitration device 40 that is disposed in the exhaust line L1 and that removes nitrogen oxide from the exhaust gas using a denitration catalyst. The denitration device 40 is disposed downstream from the air preheater 30 in the exhaust line L1, and the denitration catalyst contains 43 wt % or more of vanadium pentoxide and has a BET specific surface area of 30 m.sup.2/g or more.

An aftertreatment module is disclosed. The aftertreatment module may include a housing. The aftertreatment module may include a mounting plate within the housing that forms an inlet chamber and an outlet chamber. The aftertreatment module may include an inlet for exhaust gas from a combustion engine to flow into to the inlet chamber. The aftertreatment module may include an outlet through a top plate of the housing. The inlet and the outlet may be located on opposite sides of the housing and at opposite ends of the housing from each other. The aftertreatment module may include a set of catalysts mounted to the mounting plate. The aftertreatment module may include a diffuser plate within the inlet chamber that forms a lower portion of the inlet chamber and an upper portion of the inlet chamber. The diffuser plate may diffuse the exhaust gas through the lower portion.

Processes and systems for producing potassium sulfate as a byproduct of a desulfurization process. Sulfur dioxide is absorbed from a flue gas using an ammonia-containing solution to produce an ammonium sulfate solution that contains dissolved ammonium sulfate. At least a first portion of the ammonium sulfate solution is heated before dissolving potassium chloride therein to form a slurry that contains potassium sulfate crystals and an ammonium chloride solution. The slurry is then cooled to precipitate additional potassium sulfate crystals, after which the potassium sulfate crystals are removed to yield a residual ammonium chloride solution that contains dissolved ammonium chloride and residual dissolved potassium sulfate. Ammonia is then absorbed into the residual ammonium chloride solution to further precipitate potassium sulfate crystals, which are removed to yield a residual ammonium chloride solution that is substantially free of dissolved potassium sulfate.

The present invention describes a fluid which is suitable for the decontamination of heat engines which can carry out both the catalytic reduction of oxides of nitrogen (NOx) contained in exhaust gases and assist in the regeneration of the particulate filter (PF), said fluid being in the form of a stable suspension of colloidal particles, these colloidal particles being dispersed in an aqueous solution containing at least one reducing agent or at least one precursor of a reducing agent for NOx. The invention also describes several embodiments for the preparation of said fluid.

Disclosed herein are particulate sorbents, such as sorbents that can be used for mercury removal applications. The absorbent can comprise at least one ammonium phosphate and at least one activated carbon selected from unhalogenated activated carbon and halogenated activated carbon, wherein the halogenated activated carbon contains at least one halogen impregnant on its surface. Also disclosed are methods of making sorbents, and methods of mercury removal, e.g., from flue gas generated by coal combustion.

Systems and methods of the present invention related to an exhaust gas purification system comprising: (a) a particulate filter including an inlet and an outlet with an axial length L therebetween, wherein the filter includes an oxidation catalyst capable of generating NO.sub.2 under lean burn conditions; (b) an injector for injecting ammonia or a compound decomposable to ammonia into the exhaust gas, located downstream of the filter; and (c) a downstream catalyst comprising a selective catalytic reduction (SCR) catalyst, located downstream of the injector.