Disclosed herein is a catalytic process for producing higher olefins including three- to four-carbon olefins from ethene sources by producing an ethene-containing stream from an ethene source, and subjecting the ethene-containing stream to a catalytic oligomerization process. In this catalytic process, the catalytic oligomerization process comprises exposing the ethene-containing stream in contact with a catalyst including a mixture of a zeolite material and a zeotype material.

A catalyst includes a zeolite, wherein the zeolite has: a CHA framework; a particle size less than or equal to 100 nanometers; and a silica to alumina mole ratio in the range of about 50:1 to about 150:1. The catalyst can include a metal dopant. The catalyst can be used for purifying a product by flowing a reactant across the catalyst to form the product; and condensing or separating the product. The product can be an olefin or alkenes with an increased carbon chain. The catalyst can be used for selective catalytic reduction of nitrogen oxide or a gas to liquid reaction. A method of producing the catalyst can include selecting the concentration of a crystal growth inhibitor based on the ratio of the silica precursor and an alumina precursor such that the zeolite crystals have a mean particle size less than or equal to 100 nanometers.

A method of reducing nitrogen oxides in exhaust gas of an internal combustion engine by selective catalytic reduction (SCR) comprises contacting the exhaust gas also containing ammonia and oxygen with a catalytic converter comprising a catalyst (2) comprising at least one crystalline small-pore molecular sieve catalytically active component (Z.sub.M,I) having a maximum ring opening of eight tetrahedral basic building blocks, which crystalline small-pore molecular sieve catalytically active component (Z.sub.M,I) comprising mesopores.

A power system comprises an engine configured to combust an air/fuel mixture and produce a flow of exhaust gas; an exhaust passageway fluidly connected to the engine to receive the flow of exhaust gas; an exhaust gas recirculation loop fluidly connecting the exhaust passageway to a fuel intake for the engine; a first conversion zone containing a fuel reforming catalyst located within the exhaust gas recirculation loop; and a second conversion zone located within the exhaust gas recirculation loop separate from and downstream of the first conversion zone stream, the second conversion zone containing a fuel cracking catalyst.

A method for synthesizing small crystals of silicoaluminophosphate-34 (SAPO-34) molecular sieves with high structural purity. The method includes first forming a slurry comprising monoisopropanolamine. Then, the slurry is aged to form an aged slurry. Finally, crystallization of silicoaluminophosphate molecular sieves comprising the SAPO-34 molecular sieves is induced from the aged slurry.

Disclosed herein are methods for crystallizing aluminosilicate zeolites, including the steps of preparing a mixture containing a silica source, a mineralizing agent, an organic structure directing agent; heating the mixture to form a heated mixture; and adding an alumina source to the heated mixture. The method steps described herein can provide an accelerated aluminosilicate zeolite crystallization process as compared, e.g., to conventional processes.

The disclosure, in one aspect, relates to methods of preparing a CHA zeolite under ambient pressure conditions. In further aspects, the disclosure relates to methods such that a mother liquor can be isolated from a disclosed method, and recycled for use in a disclosed method for further preparation of a CHA zeolite. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present disclosure.

Described are SCR catalyst systems comprising a first SCR catalyst composition and a second SCR catalyst composition arranged in the system, the first SCR catalyst composition promoting higher N.sub.2 formation and lower N.sub.2O formation than the second SCR catalyst composition, and the second SCR catalyst composition having a different composition than the first SCR catalyst composition, the second SCR catalyst composition promoting lower N.sub.2 formation and higher N.sub.2O formation than the first SCR catalyst composition. The SCR catalyst systems are useful in methods and systems to catalyze the reduction of nitrogen oxides in the presence of a reductant.

The invention provides methods for a one-pot synthesis of molecular sieves of the CHA-type. The method uses molecular and non-molecular sieves as sources of silicon and aluminum. A first OSDA is selected from tetraethylenepentamine (TEPA) and triethy-lenepentamine (TETA). The synthesis mixture comprises a first metal selected from copper, iron and zinc. Optionally, the synthesis mixture may furthermore comprise a second OSDA and/or a second metal selected from manganese, cesium, magnesium, calcium, strontium, barium, yttrium, titanium, zirconium, niobium, iron, zinc, silver, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium and mixtures thereof. The molecular sieves of the CHA-type obtainable by the method can be used as SCR-catalytically active substances for the removal of nitrogen oxides from exhaust gases of combustion engines.

A method for processing polyolefins may include contacting solid polyolefins with a solid catalyst to form a reaction mixture. The solid catalyst may be chosen from a zeolite, a microporous aluminosilicate, an alumina, or combinations thereof. The solid polyolefins may be chosen from polyethylene, polypropylene, or combinations thereof. The method may include mechanically agitating the reaction mixture to produce olefin-containing hydrocarbon polymers and separating the olefin-containing hydrocarbon polymers from the solid catalyst. The olefin-containing hydrocarbon polymers include a carbon-carbon double bond in the backbone of the hydrocarbon polymers.