B01D2255/50

Methods to produce zeolites with the GME topology and compositions derived therefrom

The present disclosure is directed to microporous crystalline aluminosilicate structures with GME topologies having pores containing organic structure directing agents (OSDAs) comprising at least one piperidinium cation, the compositions useful for making these structures, and methods of using these structures. In some embodiments, the crystalline zeolite structures have a molar ratio of Si:Al that is greater than 3.5.

Selective catalytic reduction catalyst on a filter substrate

A selective catalytic reduction catalyst for the treatment of an exhaust gas stream of a passive ignition engine, the catalyst comprising a porous wall-flow filter substrate comprising an inlet end, an outlet end, a substrate axial length (w) extending between the inlet end and the outlet end, and a plurality of passages defined by porous internal walls of the porous wall flow filter substrate; wherein the catalyst further comprises a first coating, said first coating extending over x % of the substrate axial length from the inlet end toward the outlet end of the substrate, x being in the range of from 10 to 100, wherein the first coating comprises copper and an 8-membered ring pore zeolitic material; wherein the catalyst further comprises a second coating, the second coating extending over y % of the substrate axial length from the outlet end toward the inlet end of the substrate, y being in the range of from 20 to 90, wherein the second coating comprises copper, and optionally an 8-membered ring pore zeolitic material; wherein the catalyst optionally further comprises a third coating; wherein x+y is at least 90; wherein y % of w from the outlet end toward the inlet end of the substrate define the outlet zone of the coated substrate and (100−y) % of w from the inlet end toward the outlet end of the substrate define the inlet zone of the coated substrate; wherein the ratio of the loading of copper in the inlet zone, Cu(in), calculated as CuO, relative to the loading of copper in the outlet zone, Cu(out), calculated as CuO, Cu(in):Cu(out), is less than 1:1.

Catalyst for exhaust gas oxidation, method for producing same, and exhaust gas oxidation method using same

Described are a catalyst capable of effectively oxidizing an exhaust gas, a method for preparing the catalyst, and a method for oxidizing an exhaust gas using the catalyst. The exhaust gas oxidation catalyst includes at least two layers, a lower catalyst layer and an upper catalyst layer, laminated on a three-dimensional structure, wherein the lower catalyst layer and the upper catalyst layer independently contain precious metal and alumina and/or zeolite, and at least a part of the upper catalyst layer contains pores derived from a pore connecting agent with a combustion decomposition temperature of 300° C. or more to less than 450° C.

Molecular sieve intergrowths of <i>cha </i>and aft having an “<i>sfw</i>-GME tail,” methods of preparation and use

Molecular sieves comprising intergrowths of cha and aft having an “sfw-GME tail”, at least one structure directing agent (SDA) within the framework of the molecular sieve, an intergrowth of CHA and GME framework structures, cha cavities, and aft cavities are described. A first SDA comprising either an N,N-dimethyl-3,5-dimethylpiperidinium cation or a N,N-diethyl-2,6-dimethylpiperidinium cation is required. A second SDA, which can further be present, is a CHA or an SFW generating cation. The amount of the second SDA-2 used can change the proportion of the components in the cha-aft-“sfw-GME tail”. Activated molecular sieves formed from SDA containing molecular sieves are also described. Compositions for preparing these molecular sieves are described. Methods of preparing a SDA containing JMZ-11, an activated JMZ-11, and metal containing activated JMZ-11 are described. Methods of using activated JMZ-11 and metal containing activated JMZ-11 in a variety of processes, such as treating exhaust gases and converting methanol to olefins are described.

LOW TEMPERATURE NOX ADSORBER WITH ENHANCED REGENERATION EFFICIENCY

The present disclosure provides Low Temperature NO.sub.x-Absorber (LT-NA) catalyst compositions, catalyst articles, and an emission treatment system for treating an exhaust gas, each including the LT-NA catalyst compositions. Further provided are methods for reducing a NO.sub.x level in an exhaust gas stream using the LT-NA catalyst articles. In particular, the LT-NA catalyst compositions include a first zeolite, a first palladium component, and a plurality of platinum nanoparticles. The LT-NA catalyst compositions exhibit enhanced regeneration efficiency with respect to NO.sub.x adsorption capacity, even after hydrothermal aging.

METHOD FOR UNBLOCKING PORES IN A SELECTIVE CATALYTIC REDUCTION CATALYST
20220401944 · 2022-12-22 ·

The invention concerns a method for unblocking pores in a metal zeolite based selective catalytic reduction (SCR) catalyst. The method includes filling, at least partially, the SCR catalyst with a liquid, the liquid being preferably distilled water. The method includes letting said liquid inside the SCR catalyst enough time to allow said liquid to dissolve, at least partially, the obstructions and to penetrate into the pores. The method includes heating the SCR catalyst at a temperature above the ebullition temperature of the liquid so as to vaporize the part of the liquid remained into the pores, and generate steam flows through the obstructions, the steam flows removing the obstructions and unblocking the pores, wherein no hydrocarbons are injected during the step of heating.

CATALYST FOR REDUCING NITROGEN OXIDES
20220401920 · 2022-12-22 · ·

The present invention relates to a catalyst comprising a carrier substrate of length L and at least two washcoat layers A and B wherein washcoat layer A comprises alumina; ceria; an alkaline earth compound and/or an alkali compound; platinum, palladium or platinum and palladium; washcoat layer B comprises a zeolite and palladium, wherein the palladium is present as palladium cation in the zeolite structure or is wholly or partially present as palladium metal and/or as palladium oxide in the zeolite structure and/or on the surface of the zeolite structure; and
wherein washcoat layer A is arranged below washcoat layer B.

Copper CHA zeolite catalysts

Zeolite catalysts and systems and methods for preparing and using zeolite catalysts having the CHA crystal structure are disclosed. The catalysts can be used to remove nitrogen oxides from a gaseous medium across a broad temperature range and exhibit hydrothermal stable at high reaction temperatures. The zeolite catalysts include a zeolite carrier having a silica to alumina ratio from about 15:1 to about 256:1 and a copper to alumina ratio from about 0.25:1 to about 1:1.

Process for the production of a zeolitic material via interzeolitic conversion

The present invention relates to a process for the preparation of a zeolitic material SiO.sub.2 and X.sub.2O.sub.3 in its framework structure, wherein X stands for a trivalent element, wherein said process comprises interzeolitic conversion of a first zeolitic material comprising SiO.sub.2 and X.sub.2O.sub.3 in its framework structure, wherein the first zeolitic material has an FER-, TON-, MTT-, BEA-, MEL-, MWW-, MFS-, and/or MFI-type framework structure to a second zeolitic material comprising SiO.sub.2 and X.sub.2O.sub.3 in its framework structure, wherein the second zeolitic material obtained in (2) has a different type of framework structure than the first zeolitic material. Furthermore, the present invention relates to a zeolitic material per se as obtainable and/or obtained according to the inventive process and to its use, in particular as a molecular sieve, as an adsorbent, for ion-exchange, or as a catalyst and/or as a catalyst support.

DURABLE COPPER-SCR CATALYST
20220387981 · 2022-12-08 · ·

A catalyst composition for selective catalytic reduction of NO.sub.x by ammonia or compounds, such as urea, generating ammonia under exhaust gas conditions. The composition includes a) a copper ion exchanged zeolite particles having a Si/Al.sub.2 molar ratio (SAR) of 15 or less and a copper content sufficiently high to perform the catalytic reduction, b) a nanocrystalline aluminium compound in an amount sufficient for stabilizing the zeolite, and c) a zirconium compound in an amount sufficient to improve hydrothermal durability of the catalyst composition.