Characterization of Zeolite Membranes

Despite improvement to synthesis methods used it is known that all membranes possess unavoidable defects due to intercrystalline porosity, which are formed during membrane growth [7, 8]. The goal of many characterization techniques is to determine the size and concentration of such defects and evaluate how their presence affects membrane performance. 

Transport Theory and Separation Capability of Zeolite Membranes 

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Bernal MP, Coronas J, Menendez M, and Santamaria J. Characterization of zeolite membranes by measurement of permeation fluxes in the presence of adsorbable species. Ind Eng Chem Res 2004 41 5071-5078. 

S. Xiang and Y.H. Ma, Formation and characterization of zeolite membranes from sols. Paper presented at the 3rd International Coivference on Inorganic Membranes, July 10-14,1994, Worcester, MA, USA. 

Characterization of zeolite membrane quality by using permporosimtrey... 

The present review of zeolite membrane technology covers synthesis and characterization methods as well as the theoretical aspects of transport and separation mechanisms. Special attention is focused on the performance of zeolite membranes in a variety of applications including liquid-liquid, gas/vapor and reactive... 

Geus E.R., den Exter M.J. and van Bekkum H., Synthesis and characterization of zeolite (MFI) membranes on porous ceramic supports, 7. Chem. Soc. Faraday Trans. 55 3101 (1992). 

This is the area of zeolitic materials, which can be characterized as crystalline, porous materials built predominantly of oxygen, silica, and alumina (or phosphor) [1,2]. These crystals contain straight or sinusoidal channels that can be interconnected, resulting in a one-, two-, or three-dimensional pore network. At the intersections, small or large cavities may exist. Due to the crystallinity, the pores are uniform and can be prepared with great reproducibility, which is the biggest advantage over attempts to produce amorphous membranes with pores of molecular dimensions. Therefore, in the last decade much research effort has been put into the development of zeolitic membranes, and with success [3-29]. 

Roque-MaUierbe R., del VaUe W., Marquez F., Duconge J., and Goosen M.F.A., S3mthesis and characterization of zeolite-based porous ceramic membranes. Separation Science and Technology 41 2006... 

Zeolite membranes are commonly characterized by SEM, XRD. TEM, EPMA, SEM-EDX, TEM-EOS, and Nitrogen adsorption are also used to study the morphology, microstructure and composition of zeolite membranes. Usually single gas permeation, mixed gas separation, pervaporation and vapor permeation are performed to evaluate the properties of zeolite membranes. Recently, some novel characterization techniques have been applied. Infrared reflectance measurement was used to characterize membrane thickness [19]. Fluorescence confocal optical microscopy was used to image the grain boundary structure of zeolite membranes [20]. FTIR-ATR method was used to characterize the T-O vibration of zeolite membranes [21],... 

Aksoy EA, Akata B, Bac N, Hasirci N. Preparation and characterization of zeolite beta-polyurethane composite membranes. J Appl Polym Sci Jnne 2007 104(5) 3378-87. 

B. Holmberg, H. Wang, J. Norbeck and Y. Yan, Synthesis and characterization of Zeolite Y Nanocrystals for Nafion Zeolite Y composite proton exchange membranes, AIChE, Spring National Meeting, New Orleans, Los Angeles, USA, March 10-14 (2002). 

Tsuru, T., Takata, Y., Kondo, H., Hirano, F., Yoshioka, T., and Asaeda, M. (2003) Characterization of sol-gel derived membranes and zeolite membranes by nanopermporometry. Separ. Purif. Technol., 32, 23-27. 

In recent years, extensive work has been reported on the synthesis, characterization and applications of zeoUte membranes [5]. ZeoUte membranes are capable of overcoming some of the challenges facing polymer membranes. Under conditions where polymer membranes cannot be used zeolite membranes have the potential... 

Kyotani, T., Mizuno, T., Katakura, Y., Kakui, S., Shimotsuma, N., Saito, )., and Nakane, T. (2007) Characterization of mbular zeolite NaA membranes prepared from dear solutions by ETIR-ATR, GIXRD and EIB-TEM-SEM.J. Membr. Sci., 296,162-170. 

Pechar, T.W., Tspatsis, M., Marand, E., and Davis, R. (2002) Preparation and characterization of a glassy fluorinated polyimide zeolite mixed matrix membrane. Desalination, 146, 3-9. 

Jia, M., Peinemann, K.V., and Behling, R.D. (1992) Preparation and characterization of thin-film zeolite-PDMS composite membranes. /. Memhr. Sci.,... 

Ghen, X., Yang, H., Gu, Z., and Shao, Z. (2001) Preparation and characterization of HY zeolite-filled chitosan membranes for pervaporation separation. /. Appl. 

In this paper, we consider a zeolite membrane comprised of a single zeolite crystal. While real zeolite membranes are polycrystalline, this approximation is useful because many experimental studies aim to characterize transport that occurs purely through zeolite pores [6], The steady state flux, J, through this membrane is... 

M.-D. Jia, K.V. Peinemann and R.-D. Behling, Preparation and Characterization of Thin-film Zeolite-PDMS Composite Membranes, J. Membr. Sci. 73, 119 (1992). 

Semiconductor nanoclusters (quantum dots) possess chemical and physical properties that differ substantially from those of the analogous bulk solids [36-38]. Quantum dots have been synthesized using hosts such as zeolites [39], porous glass [40], micelles [41], membranes [42], and anionic polymers [43]. The synthesis and characterization of CdS quantum dots in dendrimer hosts have been studied [44-48]. Here, two PAMAM dendrimers are used one is G3.5 with surface carboxyl group and the other is G4 with surface amino group. Mixing solutions of Cd2+ and S2 in pure methanol result in a yellow precipitate of... 

To assess about the quality and purity of the synthesized membranes, several experimental techniques and procedures are available many of those are commonly employed in catalyst characterization. Thus, XRD (x-ray diffraction) analysis of the supported samples is conventionally used to identify the type of zeolite, the proportion of amorphous material and impurities, and the preferential orientation of the crystals (XRD-pole figure). However, for the vast majority of the synthesis procedures described, the XRD spectra of the scrapped membrane or the resulting powder from the liquid phase is supplied to avoid the support contribution. 

Moron F, Pina MP, Uiriolabeitia E, Menendez M, and Santamaria J. Preparation and characterization of Pd-zeolite composite membranes for hydrogen separation. Desalination 2002 147(1-3) 425M-31. 

Giroir-Fendler A, Julbe A, Ramsay JDF, and Dalmon JA. CNRS French Patent, PCT Int Appl. FR 94-5562, 940429. 1994. Giroir-Fendler A, Peureux J, Mozzanega H, and Dalmon JA. Characterization of a zeolite membrane for catalytic membrane reactor application. Stud Surf Sci Catal A 1996 101 127-136. 

Xiongfu Z, Yonsheng L, Jinqu W, Huairong T, and Changhou L. Synthesis and characterization of Fe-MFI zeolite membrane on a... 

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