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Synthesis and Characterization of Nitrogen Substituted Zeolites

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dc.contributor.advisor Grey, Clare P. en_US
dc.contributor.author Dogan, Fulya en_US
dc.contributor.other Department of Chemistry en_US
dc.date.accessioned 2012-05-15T18:02:59Z
dc.date.accessioned 2015-04-24T14:45:24Z
dc.date.available 2012-05-15T18:02:59Z
dc.date.available 2015-04-24T14:45:24Z
dc.date.issued 2010-12-01
dc.identifier Dogan_grad.sunysb_0771E_10315.pdf en_US
dc.identifier.uri http://hdl.handle.net/1951/55411 en_US
dc.identifier.uri http://hdl.handle.net/11401/70978 en_US
dc.description.abstract The interest in basic solid materials, particularly for basic zeolites has considerably increased in the last two decades because of their potential use in catalysis and separation. Basic zeolites have most often been obtained by ion-exchange or impregnation with alkali metal cations or grafting of organic bases onto zeolite pore walls. Such materials often suffer from instability and/or pore blockage, because none of these approaches places basic sites directly into the zeolite framework. Recently zeolitic materials have been made with some of the bridging oxygen atoms in Si-O-Si and/or Si-O-Al linkages replaced by NH groups, i.e. by substitution of framework oxygen by nitrogen. As a result, the basic strength of the framework increases due to the lower electronegativity of nitrogen with respect to oxygen. In this study, solid base catalysts are obtained by nitrogen substitution of the faujasite type of zeolites under ammonia flow at high temperatures. The efficiency of the reaction is tested by using zeolites with different aluminum contents and extraframework cations and varying the reaction conditions such as ammonia flow rate, reaction temperature and duration. The characterization studies show that high levels of nitrogen substitution can be achieved while maintaining porosity, particularly for NaY and low-aluminum HY zeolites, without a significant loss in the crystallinity. 27Al and 29Si MAS NMR experiments performed on the nitrogen substituted zeolites show dealumination of the framework and preferential substitution for Si-OH-Al sites at the early stages of the reaction (temperatures at 750-800 øC). No preference is seen for reactions performed at higher temperatures and longer reaction times (e.g., 850 øC and 48 h). X-ray PDF analysis performed on the modified zeolites show that the Si-N distance in the 1st shell is longer than Si-O bond distance and Si-Si/Al bond distance of the Si-O/N-Si/Al linkage decreases, as an indication of a decrease in bond angle. The basicity experiments performed on the zeolites show an increase basicity with increase of the nitrogen content. en_US
dc.description.sponsorship This work is sponsored by the Stony Brook University Graduate School in compliance with the requirements for completion of degree. en_US
dc.format Monograph en_US
dc.format.medium Electronic Resource en_US
dc.language.iso en_US en_US
dc.publisher The Graduate School, Stony Brook University: Stony Brook, NY. en_US
dc.subject.lcsh Chemistry -- Energy -- Inorganic Chemistry en_US
dc.subject.other nitridation, Pair Distribution Function, solid base catalysts, solid state NMR, zeolites en_US
dc.title Synthesis and Characterization of Nitrogen Substituted Zeolites en_US
dc.type Dissertation en_US
dc.mimetype Application/PDF en_US
dc.contributor.committeemember Michael G. White en_US
dc.contributor.committeemember Brian L. Phillips en_US
dc.contributor.committeemember Jonathan C. Hanson. en_US

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