TY - JOUR
T1 - Preparation of zeolite-coated cordierite honeycombs prepared by an in situ crystallization method
AU - Okada, Kiyoshi
AU - Kameshima, Yoshikazu
AU - Madhusoodana, Chengala D.
AU - Das, Rathindra N.
N1 - Funding Information:
This study is supported by The COE Project (Tokyo Tech./Industry Collaboration for Nanomaterial Frontier Cultivation). CDM wishes to thank UNESCO/Monbusho and JSPS for the research fellowship. We are also grateful to Professor K.J.D. MacKenzie of Victoria University of Wellington for critical reading and editing of the manuscript.
PY - 2004/7
Y1 - 2004/7
N2 - Zeolite thin films were prepared on cordierite (Mg2Al 4Si5O18) honeycomb substrates by in situ crystallization using soft hydrothermal conditions. The synthesized zeolite films (zeolite A and ZSM-5) were characterized by XRD, FTIR, SEM, NH 3-TPD, and Ns2 and propane gas adsorption. Zeolite-A films were prepared by dip-coating on a cordierite substrate in a precursor of molar composition of Na2O:Al2O3: SiO2: H2O=4:1:2:100 and heating in an autoclave at 80 °C for 6-10 h. The resultant zeolite-A films consisted of cubic crystals about 2-3 μm in size, achieving a thickness of 20 μm after re-coating. ZSM-5 films were similarly formed using a microporous silica precursor obtained by selective leaching of metakaolinite with tetrapropylammonium hydroxide (TPAOH) as the templating agent. The molar composition of the precursor was NaOH:microporous silica:TPAOH:H2O=1:10:1:200. The dipped substrate covered with the wet precursor gel was heated in an autoclave at 150 °C for 24 h. The resultant films were composed of short prismatic <1 μm crystals achieving thickness of several to 10 μm after re-coating. The microstructure and porous properties of the ZSM-5 films were found to change according to the chemical composition and surface treatment of the cordierite substrates. The presence of a SiO2-rich interfacial layer between the substrate and zeolite film increased the amount of zeolite formed and the physical adsorption but decreased the solid acidity and amount of chemisorption.
AB - Zeolite thin films were prepared on cordierite (Mg2Al 4Si5O18) honeycomb substrates by in situ crystallization using soft hydrothermal conditions. The synthesized zeolite films (zeolite A and ZSM-5) were characterized by XRD, FTIR, SEM, NH 3-TPD, and Ns2 and propane gas adsorption. Zeolite-A films were prepared by dip-coating on a cordierite substrate in a precursor of molar composition of Na2O:Al2O3: SiO2: H2O=4:1:2:100 and heating in an autoclave at 80 °C for 6-10 h. The resultant zeolite-A films consisted of cubic crystals about 2-3 μm in size, achieving a thickness of 20 μm after re-coating. ZSM-5 films were similarly formed using a microporous silica precursor obtained by selective leaching of metakaolinite with tetrapropylammonium hydroxide (TPAOH) as the templating agent. The molar composition of the precursor was NaOH:microporous silica:TPAOH:H2O=1:10:1:200. The dipped substrate covered with the wet precursor gel was heated in an autoclave at 150 °C for 24 h. The resultant films were composed of short prismatic <1 μm crystals achieving thickness of several to 10 μm after re-coating. The microstructure and porous properties of the ZSM-5 films were found to change according to the chemical composition and surface treatment of the cordierite substrates. The presence of a SiO2-rich interfacial layer between the substrate and zeolite film increased the amount of zeolite formed and the physical adsorption but decreased the solid acidity and amount of chemisorption.
KW - Hydrothermal treatment
KW - In situ crystallization
KW - Microstructure
KW - Porous properties
KW - Zeolite films
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U2 - 10.1016/j.stam.2004.03.001
DO - 10.1016/j.stam.2004.03.001
M3 - Article
AN - SCOPUS:3042692193
SN - 1468-6996
VL - 5
SP - 479
EP - 484
JO - Science and Technology of Advanced Materials
JF - Science and Technology of Advanced Materials
IS - 4
ER -