Change search
ReferencesLink to record
Permanent link

Direct link
Synthesis and characterization of the DDR type zeolite
2007 (English)Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
Abstract [en]

Separation of light gases by adsorption is considered to be one of the promising applications of zeolite membranes. DDR type zeolites possessing extremely fine pore structure are regarded as good candidates to be utilized for this purpose. In order to prepare a membrane using a seeding technique, small seed crystals should be available. For the moment very few methods of DDR type zeolites synthesis exist and limited amount of publications describing their properties are to be found. In this work, DDR type zeolite crystals syntheses were performed according to the methods described by den Exter et al. and claimed in the patents by A. Stewart and K. Nakayama et al. The samples obtained in this work were characterized by XRD, SEM, BET, FT-IR and FT-Raman spectroscopy. DD3R clathrasil crystals were successfully synthesized following the procedure suggested by den Exter et al. when seeding with Sigma-1 seed crystals. But this method might be considered quite inconvenient owing to long synthesis time (25 days) and stirring required in order to get pure DD3R clathrasil. The method of DD3R film preparation claimed by K. Nakayama was considered to be not suitable for DD3R crystals synthesis since we were not able to reproduce the results reported in the patent. The procedure of Sigma-1 crystals synthesis claimed by A. Stewart was found to be simple and although the sample obtained was partially amorphous, it was of sufficient quality to be used as seed crystals in DD3R synthesis. It was noticed that proper stirring was required in order to get uniformly sized and shaped crystals. X-ray diffraction was used for samples identification complemented by FT- Raman and FT-IR spectroscopy. Crystal size and morphology were investigated using scanning electron microscopy. All the mentioned techniques allowed revealing impurities and evaluating an approximate degree of crystallinity of the samples obtained. Finally, pore structure and sorption properties were studied by means of nitrogen adsorption/desorption measurements.

Place, publisher, year, edition, pages
Keyword [en]
Physics Chemistry Maths, DD3R, Clathrasil, Sigma-1, Zeolite, Gas separation, Molecular sieve
Keyword [sv]
Fysik, Kemi, Matematik
URN: urn:nbn:se:ltu:diva-57551ISRN: LTU-DUPP--07/077--SELocal ID: e351b8e9-d41d-4dde-9d57-049207d36654OAI: diva2:1030939
Subject / course
Student thesis, at least 15 credits
Educational program
Chemical Engineering, master's level
Validerat; 20101217 (root)Available from: 2016-10-04 Created: 2016-10-04Bibliographically approved

Open Access in DiVA

fulltext(2984 kB)0 downloads
File information
File name FULLTEXT01.pdfFile size 2984 kBChecksum SHA-512
Type fulltextMimetype application/pdf

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

ReferencesLink to record
Permanent link

Direct link