Abstract:
The present invention relates to an organotemplate-free synthetic process for the production of a zeoiitic material having a CHA-type framework structure comprising YO2, X2O3, and optionally comprising Z2O5, wherein said process comprises the steps of: (1 ) providing a mixture comprising one or more sources for YO2, one or more sources for X2O3, and seed crystals having a CHA framework structure, wherein the CHA framework structure of the seed crystals comprises YO2, X2O3, and optionally comprises Z2O5; and (2) crystallizing the mixture obtained in step (1 ); wherein Y is a tetravaient element, X is a trivalent element, and Z is a pentavalent element, wherein optionally one or more sources for Z2O5 are further provided in step (1 ), and wherein if the CHA framework of the seed crystals does not contain Z2O5, the seed crystals then have a Y02 : X2O3 molar ratio of 5 or greater than 5.
Abstract:
The present invention relates to an organotemplate-free synthetic process for the production of a zeolitic material comprising YO2 and X2O3, wherein said process comprises the steps of (1) preparing a mixture comprising seed crystals, one or more sources for YO2, one or more sources for X2O3, and one or more solvents; (2) crystallizing the mixture obtained in step (1) to obtain a zeolitic material comprising YO2 and X2O3 as a crystallization product; wherein Y is a tetravalent element, and X is a trivalent element, and wherein at least a portion of the mother liquor obtained in step (2) is recycled to step (1) as a source for YO2, optionally after concentration of the mother liquor.
Abstract:
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.
Title translation:BIMETALL-AUSGETAUSCHTER ZEOLITH-BETA AUS ORGANOTEMPLATE-FREIER SYNTHESE UND VERWENDUNG DAVON IN DER SELKKTIVEN KATALYTISCHEN NOX-REDUKTION
Abstract:
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).
Abstract:
A process for the preparation of a zeolitic material having a structure comprising YO2 and X2O3 is provided, wherein said process comprises the steps of ( 1 ) providing a mixture comprising one or more ammonium compounds of which the ammonium cation has the formula (I): [R1R2NR3R4+(I) and further comprising one or more sources for Y02 and one or more sources for X2O3; (2) crystallizing the mixture provided in step ( 1 ); wherein Y is a tetravalent element, and X is a trivalent element, and wherein the ammonium compounds are preferably derivatized or underivatized N,N-dimethylpyrrolidinium compounds, Nu,Nu-dimethylpiperidinium compounds, Nu,Nu-dimethylhexahydroazepinium compounds, and mixtures thereof, and wherein the molar ratio of ammonium cation having the formula (I) to Y in the mixture provided in step (1) and crystallized in step (2) is equal to or greater than 0.25.