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This text is divided into two parts; the first part gives a short recapitulation of the development status of the electrochemical reactor for soot removal, while the second part gives a description of activities on electrochemical NOx reduction. The Electrochemical Reactor for filtration and continuous combustion of soot from diesel exhaust gas has been described earlier [1, 2]. The reactor size has been increased by stacking flat plate reactors, and full size test has been performed on a diesel engine in a test bench. The soot removal efficiency is better than 90%, but the efficiency for gas oxidation (conversion of carbon monoxide (CO) and hydrocarbons (CH)) is still low, of the order of 50%. The packing and mounting of the reactor is under development to avoid mechanical breakage by engine vibrations. This has improved the durability significantly, and on road vehicle test is under initiation.

A concept for an electrochemical reactor acting as a trap for the removal of soot particles from diesel exhaust gas has been developed and presented earlier [1]. Only small scale flat plate samples tested with synthetic exhaust gas was presented. Since then, the sample size has been increased, and test on a diesel engine in a test bench has been carried out. Various concepts for the establishment of a sufficient filtering surface and for the electrical connections have been tested, and the construction of a muffler with an electrochemical reactor installed has been initiated. This is to be on a passenger car for on-road test. The preliminary bench test indicates a soot removal efficiency of 75-90% with no accumulation of soot at the reactor, at temperatures above 250°C. A separate project has been started to evaluate the possibilities of lean NOx removal on a similar reactor. Results from this will be reported separately.