|
Title:
|
|
Microporous sol-gel membranes for molecular separations
|
|
|
|
Author(s):
|
|
|
|
|
|
Published by:
|
Publication date:
|
|
ECN
Energy Efficiency in Industry
|
14-5-2007
|
|
|
|
ECN report number:
|
Document type:
|
|
ECN-W--07-020
|
Article (scientific)
|
|
|
|
Number of pages:
|
|
|
19
|
|
Published in: Ann. Chim. Sci. Mat. (Elsevier), , 2007, Vol.32(2), p.231-244.
Abstract:
Molecular separations are very important in many production processes and they account for considerable energy consumption. Microporous membranes are a very efficient alternative to the very energy-intensive and widely-used distillation. Sol-gel membranes offer many opportunities in this respect because of the wide variety of materials and pore structures that can be made. The cost of such membranes is generally dominated by the cost of the support structure that must be of very high quality due to the hierarchical nature of the asymmetrical membrane system (a hole in the support will give a defect in the membrane). The selectivity is very strongly depending on pore characteristics and defect status and thus controlling the manufacturing parameters is essential for reproducible production. Employing proper characterisation techniques in a prudent way is important for effective membrane development and eventual efficient membrane production. Next to the issue of reproducible membrane production on large scale there remains the issue of membrane stability and sufficient long-term performance in industrial applications. As sol-gel membranes have an amorphous structure and a very high specific surface area there is a significant driving force to transform into a structure with a lower energy state. Active operation of sol-gel membranes seems to accelerate this transformation and the challenge is to reduce the kinetics of this process to obtain membranes with sufficient life-time for industrial applications.
Back to List