摘要:
Described is a process for the production of a zeolitic material having an LEV-type framework structure comprising YO2 and optionally comprising X2O3, wherein said process comprises: (1) preparing a mixture comprising one or more sources for YO2, one or more solvents, and optionally comprising seed crystals; and (2) crystallizing the mixture obtained in step (1); wherein Y is a tetravalent element, and X is a trivalent element, wherein the zeolitic material optionally comprises one or more alkali metals M, wherein the molar ratio of the total amount of the one or more solvents to the total amount of the one or more sources for YO2 based on YO2 is 9.5 or less, and wherein for crystallization temperatures of 175° C. or higher in step (2), the duration of crystallization at those temperatures is less than 14 d, as well as to a zeolitic material, preferably being obtainable or obtained according to the inventive process, said zeolitic material having an LEV-type framework structure comprising YO2 and X2O3, wherein the zeolitic material optionally comprises one or more alkali metals M, and wherein the zeolitic material displays an Y:X atomic ratio of from 1 to 9.4.
摘要:
The present invention relates to a pillared silicate compound comprising a layered silicate structure, and bridging metal atoms located between adjacent silicate layers of the silicate structure, wherein said bridging metal atoms form at least one covalent bond to each of the adjacent silicate layers, as well as a process for the preparation of a pillared silicate compound, and further includes a pillared silicate compound obtainable and or obtained according to said process, as well as a method of catalyzing a chemical reaction comprising the step of contacting one or more chemical compounds with the any of the aforementioned pillared silicate compounds.
摘要:
The present invention relates to a process for the preparation of a zeolitic material having a BEA framework structure comprising the steps of: (i) providing one or more zeolitic materials having a BEA framework structure, wherein the BEA framework structure comprises YO2 and X2O3, wherein Y is a tetravalent element, and X is a trivalent element; (ii) subjecting the one or more zeolitic materials provided in step (i) to a procedure for removing at least a portion of X, preferably tetrahedrally coordinated X, from the BEA framework structure; wherein the Y:X molar ratios of the one or more zeolitic materials provided in step (i) are respectively comprised in the range of from 1 to 50.
摘要:
The present invention relates to a process for the production of a zeolitic material having a BEA-type framework structure comprising YO2 and X2O3, wherein said process comprises the steps of (1) preparing a mixture comprising one or more sources for YO2 and one or more sources for X2O3; (2) crystallizing the mixture obtained in step (1); (3) subjecting the zeolitic material having a BEA-type framework structure obtained in step (2) to an ion-exchange procedure with Cu; and (4) subjecting the Cu ion-exchanged zeolitic material obtained in step (3) to an ion-exchange procedure with Fe; wherein Y is a tetravalent element, and X is a trivalent element, wherein the mixture provided in step (1) and crystallized in step (2) further comprises seed crystals comprising one or more zeolitic materials having a BEA-type framework structure, and wherein the mixture provided in step (1) and crystallized in step (2) does not contain an organotemplate as a structure-directing agent, as well as to the zeolitic material having a BEA frame work structure per se, and to its use, in particular in a method for the treatment of NOx by selective catalytic reduction (SCR).