Abstract:
Stickoxid-Speicherkatalysatoren werden zur Entfernung der im mageren Abgas von so genannten Magermotoren enthaltenen Stickoxide verwendet. Sie unterliegen durch die Belastung mit hohen Temperaturen im Fahrbetrieb thermischen Alterungsprozessen, die sowohl die Stickoxid-Speicherkomponenten als auch die alskatalytisch aktive Komponenten enthaltenen Edelmetalle betreffen. Die vorliegende Erfindung stelltein Verfahren zur Verfügung, mitdem die infolge des thermischen Alterungsprozesses verloren gegangene katalytische Aktivität eines Stickoxid-Speicherkatalysators, der neben Platin als katalytisch aktiver Komponente basische Verbindungen des Strontiums und/oder Bariums auf einem Ceroxid enthaltenden Trägermaterialenthält, wenigstens zum Teil wiederhergestelltwerden kann. Das zweistufige Verfahren beruht darauf, daß während der thermischen Alterung gebildete Strontium und/oder Bariumverbindungen mit dem Trägermaterial, die auch Platin enthalten, durch gezielte Behandlung mit speziellen Gasmischungen in die katalytisch aktiven Formen rücküberführt werden.
Abstract:
The present disclosure provides a macroporous noble metal catalyst and processes employing such catalysts for the regeneration of deactivated ionic liquid catalyst containing conjunct polymer.
Abstract:
One embodiment of the present invention is a method for charging a depleted or spent solid storage media with ammonia. Other embodiments include unique methods, systems, devices, and apparatus involving charging spent solid storage media with ammonia. Further embodiments, forms, objects, aspects, benefits, and advantages of the present invention shall become apparent from the figure and description provided herewith.
Abstract:
The present disclosure provides a macroporous noble metal catalyst and processes employing such catalysts for the regeneration of deactivated ionic liquid catalyst containing conjunct polymer.
Abstract:
Method for the preparation of a metal-exchanged zeolites or mixtures of metal-exchanged zeolites, such as Cu-SSZ-13, Cu-ZSM-5, Cu-beta, or Fe-beta, comprising the steps of providing a dry mixture of a) one or more microporous zeotype materials that exhibit ion exchange capacity and b) one or more metal compounds; heating the mixture in a gaseous atmosphere containing ammonia to a temperature lower than 300° C. for a time sufficient to initiate and perform a solid state ion exchange of ions of the metal compound and ions of the zeolite material; and obtaining the metal-exchanged zeolite material.
Abstract:
Method for the preparation of a metal exchanged crystalline microporous metalloaluminophosphate or mixtures containing metal exchanged microporous metalloaluminophosphates materials comprising the steps of providing a dry mixture containing a) one or more metalloaluminophosphates starting materials that exhibit ion exchange capacity, and b) one or more metal compounds; heating the mixture in a gaseous atmosphere containing ammonia to a temperature and for a time sufficient to initiate and perform a solid state ion exchange of ions of the metal compound and ions of the crystalline microporous material; and obtaining the metal-exchanged microporous metalloaluminophosphate material or mixtures containing the metal-exchanged microporous metalloaluminophosphate material.
Abstract:
Disclosed is a method for preparing diamino-dicyclohexyl methane (H12MDA) by hydrogenation of diamino-diphenyl methane (MDA). In the process, 4,4′-MDA used as the starting material is firstly hydrogenated to prepare 4,4′-H12MDA. When the activity of the catalyst is reduced, the feed is switched from 4,4′-MDA to the mixture of 2,4′-MDA and 4,4′-MDA, and then when the conversion is stabilized, the feed is switched to 4,4′-MDA again. The deactivated catalyst is activated on line by switching the feed to the mixture of 2,4′-MDA and 4,4′-MDA. 4,4′-H12MDA having the trans-trans isomer content of 16˜24 wt % is produced, and the mixture of 2,4′-H12MDA and 4,4′-H12MDA is also produced, wherein the content of 2,4′-H12MDA in the mixture is 4˜15 wt %.
Abstract:
[Object]The invention provides catalysts that are not corroded in acidic electrolytes or at high potential and have excellent durability and high oxygen reducing ability.[Solution]A catalyst of the invention includes a metal oxycarbonitride that contains titanium and at least one metal (hereinafter, also referred to as “metal M” or simply “M”) selected from silver, calcium, strontium, yttrium, ruthenium, lanthanum, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium.
Abstract:
Nitrogen oxide storage catalysts are used to remove the nitrogen oxides present in the lean exhaust gas of lean-burn engines. As a result of the stress due to high temperatures in vehicle operation, they are subject to thermal aging processes which affect both the nitrogen oxide storage components and the noble metals present as catalytically active components. The present invention provides a process with which the catalytic activity of a nitrogen oxide storage catalyst which comprises, in addition to platinum as a catalytically active component, basic compounds of strontium and/or barium on a support material comprising cerium oxide, said catalytic activity being lost owing to the thermal aging process, can be at least partly restored. The two-stage process is based on the fact that strontium and/or barium compounds formed during the thermal aging with the support material, which also comprise platinum, are recycled to the catalytically active forms by controlled treatment with specific gas mixtures.