摘要:
Disclosed are processes for the preparation of copper containing molecular sieves with the CHA structure having a silica to alumina mole ratio greater than about 10, wherein the copper exchange step is conducted via wet state exchanged and prior to the coating step and wherein in the copper exchange step a liquid copper solution is used wherein the concentration of copper is in the range of about 0.001 to about 0.25 molar using copper acetate and/or an ammoniacal solution of copper ions as copper source. Catalysts made by the processes, catalyst systems and methods of treating exhaust gas with the molecular sieves and catalysts are also disclosed.
摘要:
Catalysts, systems and methods are described to reduce NOx emissions of an internal combustion engine. In one embodiment, an emissions treatment system for an exhaust stream is provided having a catalyst comprising silver and a platinum group metal on a particulate alumina support, the atomic fraction of the platinum group metal being less than or equal to about 0.25. Methods of manufacturing catalysts are described in which silver is impregnated on alumina particles.
摘要:
Zeolites, improved methods for their synthesis, and catalysts, systems, and methods of using these zeolites as catalysts are described. The method of synthesis of the zeolites includes forming a mixture including a zeolitic precursor material and a structure directing agent and subjecting the mixture to high shear processing conditions.
摘要:
The hydroisomerization of a paraffinic hydrocarbon feedstock obtained from renewable sources is effectively achieved by passing the feedstock in the presence of hydrogen over a hydroisomerization catalyst comprising a crystalline metal silicate molecular sieve, in which a portion of the crystalline framework contains iron.
摘要:
Described are catalyst compositions, catalytic articles, methods of manufacturing catalytic articles and exhaust gas treatment systems and methods that utilize the catalytic articles. The catalytic articles include a washcoat of platinum group metal on refractory oxide support particles, and further including a molecular sieve wherein greater than 90% of the molecular sieve particles have a particle size greater than Ιμιη.