Speaking of ceramics, Coen van Gulijk, a former PhD student in the Reactor and Catalysis Engineering Department at Delft University of Technology in The Netherlands, has developed a soot filter for diesel engines that consists of a series of perforated ceramic foams. The surface of the ceramic is impregnated with a catalyst that enables a controlled oxidation or burning of soot into CO2, says van Gulijk. Ash particles from impurities in the diesel, which enter the filter with the soot, remain in the pores of the ceramic foam plates. Because it can absorb a large quantity of ash before it risks becoming blocked, van Gulijk says that the ceramic foam will last a long time. Although existing filter systems are easily blocked by heavy diesel oil (a heavy fuel that contains many ash-producing minerals and metals), van Gulijk's filter is highly suitable for such oil. An advantage of this filter, according to the developer, is that because it is built from separate filter plates instead of a single block, it is almost indestructible. Even if all of the plates were to break, the filter function remains intact. A built-in open canal prevents the filter from becoming blocked. However, a disadvantage of the design is that it requires a lot of space. This means it is not suitable for cars but it can be used for ships, which often use heavy diesel oil, and fixed motors or trains. Currently, the technology is not commercially available, as van Gulijk is trying to find partners for pilot-scale testing. For more information, contact Coen van Gulijk at phone 31-15-284-3283, fax 31-15-284-3963, or e-mail firstname.lastname@example.org.