Abstract

A catalytic muffler is described with reference to three preferred embodiments. In the first embodiment, a cylindrical entry tube having peripheral holes passes into the interior of the muffler, a second cylindrical tube having peripheral holes offset from the peripheral holes in the entry tube surrounds the entry tube, a cartridge containing a catalytic converter surrounds the second tube, and an exit tube leads from a point in the interior of the muffler external to the cartridge to the exterior of the muffler. In the second embodiment, the entry tube is branched within the muffler, and each branch is surrounded by a cartridge containing a catalytic converter. In the third embodiment, the entry tube, the second tube, and the cartridge all have cross-sections in the shapes of racetracks the major and minor axes of which are coincident. In all three embodiments, the cartridge is filled with asbestos fibers impregnated first with sodium and then with copper sulfate.