Ceramics for Sustainable Energy Technologies with a Focus on Polymer-Derived Ceramics - Novel Combustion Concepts for Sustainable Energy Development - page 495

manufacturing, allows not only for the compliance with increasingly stringent
legislative regulations in the fields of energy consumption and emission control, but

also for a higher ef ciency and, subsequently, a higher cost-effectiveness. Specif-

ically, there is signi cant interest in developing refractories with higher thermal

insulation capacity. Another area of focus is the development of processes that can
reduce the energy requirements and greenhouse gas emission in the production of
commodity building ceramics such as bricks, cement, and glass. Most of this work
is being conducted in house by manufacturers, and there is little on this topic in the
open literature.

1.1.5 Environmental Systems

Environmental systems include technologies for the reduction and/or puri cation of

solid, liquid, and gaseous emissions, the remediation of waste, as well as the
monitoring of potentially harmful or undesired compounds in natural and industrial
environments. Ceramic materials play an important role in many of these appli-
cations. Speci

filtration and purification stem from
the combination of high temperature and corrosion stability with high mechanical
strength, leading to typical uses in the

c advantages of ceramics for

filtration of particulates from diesel engine
exhaust gases, or uses in industrial processes where hot corrosive gases are present
(Schef

er and Colombo 2005 ). Since porous structures are generally required for
these applications, a wide variety of methods have been developed for the gener-
ation of processing of porous ceramics,

fl

including replicate techniques, direct

foaming, or the use of sacri cial porogens.

Porous ceramics, e.g., SiC, have also been used in heterogeneous

catalysis

applications, primarily as catalyst supports. A combination of both filtration and

catalysis functions exists in multifunctional reactors, promising a reduction in

filtration of par-
ticulates from diesel engine exhaust gases with subsequent soot

financial and instrumental expenditure. Ceramic devices for the

combustion
functionalities are an economically important example for this concept (Schef

-

er
and Colombo 2005 ). Several authors of this paper have been engaged in research on
porous ceramics, and their work is summarized in Sect. 2.3 .
Ceramic membranes are being increasingly considered for gas separation
applications (Li 2007 ). Examples for the use of ceramic gas separation membranes
are the extraction of energy carriers such as H 2 or CH 4 from product gas streams in
coal gasi

fl

cation, steam reforming, or biogas production, or the removal of H 2 O and
H 2 S impurities from hydrocarbon streams. Gas separation in ceramic membranes
can take place either by selective ion conduction using mixed ion-conducting
ceramics such as perovskite-type compounds for oxygen or hydrogen separation, or
by utilizing microporous structures for size exclusion phenomena, e.g., by using
zeolites or microporous silica. Closely related are advances in CO 2 capture and
storage (CCS) technology, allowing for the sequestration of CO 2 from fl flue gas of

combustion processes, with an aim to effectively inhibit its emission into the

atmosphere. In this application field, the use of ceramic membranes — again