Abstract:
Disclosed are processes for the preparation of copper containing molecular sieves with the CHA structure wherein the copper is exchanged into the Na+-form of the Chabazite, using a liquid copper solution wherein the concentration of copper is in the range of about 0.001 to about 0.4 molar. Also described are copper containing molecular sieves with the CHA structure, catalysts incorporating molecular sieves, systems and methods for their use.
Abstract:
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.
Abstract:
Described is a selective catalytic reduction catalyst comprising a zeolitic framework material of silicon and aluminum atoms, wherein a fraction of the silicon atoms are isomorphously substituted with a tetravalent metal. The catalyst can include a promoter metal such that the catalyst effectively promotes the reaction of ammonia with nitrogen oxides to form nitrogen and H20 selectively over a temperature range of 150 to 650 °C. In another aspect, described is a selective catalytic reduction composite comprising an SCR catalyst material and an ammonia storage material comprising a transition metal having an oxidation state of IV. The SCR catalyst material promotes the reaction of ammonia with nitrogen oxides to form nitrogen and H20 selectively over a temperature range of 150 °C to 600 °C, and the SCR catalyst material is effective to store ammonia at temperatures of 400 °C and above. A method for selectively reducing nitrogen oxides, and a method for simultaneously selectively reducing nitrogen oxide and storing ammonia are also described. Additionally, an exhaust gas treatment system is also described.
Abstract:
Described is a selective catalytic reduction catalyst comprising a zeolitic framework material of silicon and aluminum atoms, wherein a fraction of the silicon atoms are isomorphously substituted with a tetravalent metal. The catalyst can include a promoter metal such that the catalyst effectively promotes the reaction of ammonia with nitrogen oxides to form nitrogen and H20 selectively over a temperature range of 150 to 650 °C. In another aspect, described is a selective catalytic reduction composite comprising an SCR catalyst material and an ammonia storage material comprising a transition metal having an oxidation state of IV. The SCR catalyst material promotes the reaction of ammonia with nitrogen oxides to form nitrogen and H20 selectively over a temperature range of 150 °C to 600 °C, and the SCR catalyst material is effective to store ammonia at temperatures of 400 °C and above. A method for selectively reducing nitrogen oxides, and a method for simultaneously selectively reducing nitrogen oxide and storing ammonia are also described. Additionally, an exhaust gas treatment system is also described.
Abstract:
processo para a preparação de peneiras moleculares, peneiras moleculares, catalisador, uso de um catalisador, sistema de tratamento de gás de descarga, e, método para a redução seletiva de óxidos de nitrogênio. são expostos processos para a preparação de peneiras moleculares contendo cobre, com a estrutura de cha, tendo uma rezão molar de sílica para alumina maior do que cerca de 10, em que o estágio de troca de cobre é conduzido através de troca em estado úmido e e antes do estágio de revestimento, em que no estágio de troca de cobre, uma solução de cobre líquida é usada, em que a concentração de cobre está em uma faixa de cerca de 0,001 a cerca de 0,25 molar, usando o acetato de cobre e/ou uma solução amoniacal de ínos de cobre como a fonte de cobre. os catalisadores produzidos através dos processos, sistemas de catalisador e método de tratamento de gás de descarga com peneiras moleculares e catalisadores são também expostos.
Abstract:
Se describen procesos para la preparación de cobre que contiene tamices moleculares con la estructura de CHA en donde el cobre se intercambia en la forma de Na+ de la Chabazita, usando una solución de cobre líquida en donde la concentración de cobre está en el rango de aproximadamente 0.001 a alrededor de 0.4 molar. También se describen tamices moleculares que contiene cobre con la estructura de CHA, los catalizadores incorporando tamices moleculares, sistemas y métodos para su uso.
Abstract:
Disclosed are processes for the preparation of copper containing molecular sieves with the CHA structure wherein the copper is exchanged into the Na+-form of the Chabazite, using a liquid copper solution wherein the concentration of copper is in the range of about 0.001 to about 0.4 molar. Also described are copper containing molecular sieves with the CHA structure, catalysts incorporating molecular sieves, systems and methods for their use.
Abstract:
DISCLOSED ARE PROCESSES FOR THE PREPARATION OF COPPER CONTAINING MOLECULAR SIEVES WITH THE CHA STRUCTURE WHEREIN THE COPPER IS EXCHANGED INTO THE Na⁺-FORM OF THE CHABAZITE, USING A LIQUID COPPER SOLUTION WHEREIN THE CONCENTRATION OF COPPER IS IN THE RANGE OF ABOUT 0.001 TO ABOUT 0.4 MOLAR. ALSO DESCRIBED ARE COPPER CONTAINING MOLECULAR SIEVES WITH THE CHA STRUCTURE, CATALYSTS INCORPORATING MOLECULAR SIEVES, SYSTEMS AND METHODS FOR THEIR USE. (FIGURE 1)