Preparation of Zeolite T Membranes by a Two-Step Temperature Process for CO sub(2) Separation

A thin and well-intergrown zeolite T membrane with high CO sub(2) permeability and selectivity was rapidly prepared on seeded tubular supports by the two-step varying-temperature hydrothermal synthesis process (two-step method). The influence of synthesis parameters such as synthesis temperature and...

Full description

Saved in:
Bibliographic Details
Published in:Industrial & engineering chemistry research 2013-11, Vol.52 (46), p.16364-16374-16364-16374
Main Authors: Zhang, Xiao-Liang, Qiu, Ling-Fang, Ding, Min-Zheng, Hu, Na, Zhang, Fei, Zhou, Rong-Fei, Chen, Xiang-Shu, Kita, Hidetoshi
Format: Article
Language:English
Subjects:
Carbon dioxide
Crystal growth
Crystallization
Membranes
Reluctance
Separation
Synthesis
Zeolites
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:A thin and well-intergrown zeolite T membrane with high CO sub(2) permeability and selectivity was rapidly prepared on seeded tubular supports by the two-step varying-temperature hydrothermal synthesis process (two-step method). The influence of synthesis parameters such as synthesis temperature and crystallization time during the two-step durations on crystals growth and separation performance was investigated systematically. The X-ray diffraction (XRD), scanning electron microscopy (SEM), and gas permeation measurements were used to characterize the as-synthesized membranes. Compared with the conventional hydrothermal synthesis at a constant temperature (one-step method), the two-step method is more effective to synthesize a thin and continuous zeolite membrane layer in short time, which fully covered the support surface. Membrane synthesis temperature during the two-step durations could seriously influence the crystal growth and CO sub(2) separation properties. It was found that a lower temperature favored nucleation, while a higher crystallization temperature promoted crystallization during the two-step method, thus improving zeolite T crystal growth and membrane separation properties. The membranes prepared by the two-step method under the optimized conditions exhibited good reproducibility, high CO sub(2) permeance, and relatively high permselectivity for the separation of CO sub(2) from CH sub(4) or N sub(2) gas mixtures. For example, CO sub(2) permeance and CO sub(2)/CH sub(4) selectivity of the membranes reached 6.2 10 super(-8) mol m super(-2) s super(-1) Pa super(-1) and 80 for the equimolar CO sub(2)/CH sub(4) binary gaseous mixtures at 35 degree C, respectively.
ISSN:0888-5885
1520-5045
DOI:10.1021/ie4025402