Patent ID: 7497998

Claim:
A converter comprising: an exterior shell having a central axis, at least one gas inlet and at least one gas outlet, the exterior shell including a base and an interior support structure; a plurality of vertically stacked catalytic chambers within the exterior shell and in communication with at least one gas inlet and at least one gas outlet, each chamber defined by an inner wall of the exterior shell, a permeable catalytic bed support platform, a lower division plate spaced below the platform defining a gas retention plenum and an upper division plate above the platform; wherein at least one of: said platform; said upper division plate; and said lower division plate having: a toroid surface symmetric about the central axis; an outer periphery supported by the inner wall of the exterior shell; and an inner periphery supported by the interior support structure, wherein the upper division plate and the lower division plate of each chamber in operation resist a pressure differential between a higher operational pressure and a lower operational pressure, and wherein the upper division plate and the lower division plate of each chamber is concave toward the higher operational pressure and convex toward the lower operational pressure.