Abstract: The invention is a catalytic air cleaner made from a double spiral formed by winding together two strips of metal. The strips are coated with a combustion catalyst. One spiral passage leads into the core of the spiral and the other passage leads out of the core. An electric resistance heater supplies heat at the core of the spiral. The outflowing air transfers this heat to the inflowing air, through the walls of the spiral. Because of this heat exchange, the difference between the temperature of the air at the core and the air entering the spiral can be many times the difference between the temperature of the air entering and leaving the spiral. Contaminants in the air are burned on the catalytic surface with a minimum input of heat. The invention also includes a method of designing a spiral having optimum characteristics.

Abstract: The invention discloses a method of binding a metal, capable of forming a metal hydride, to a surface. The invention also includes a composition which can be applied to a surface, and which can be repeatedly hydrided and dehydrided. According to the invention, a metal capable of forming a metal hydride is pulverized, mixed with a binder, and coated onto a support. The choice of the binder is an important aspect of the invention. Because of the expansion and contraction of the metal, due to the hydriding and dehydriding, the binder must be quite elastic. The binder must also be permeable to hydrogen, and must be heat stable. Silicone rubbers meet these requirements, and can be used as binders.

Abstract: A metal support for a catalyst is disclosed, which is suitable for use in a catalytic converter for an automobile. The support generally does not interact with the catalyst, even at high temperatures, and the catalyst therefore retains its activity for a long period. The support includes a base metal containing chromium, aluminum and silicon, the remainder of the base metal being mostly iron. The specific percentages of chromium, aluminum, and silicon in the base metal can be varied according to a formula. The base metal is coated with a layer of metallic aluminum. A catalyst is applied to the support, preferably by first coating the support with a layer of alumina, and then impregnating the alumina layer with a suitable combustion catalyst. The support can be rolled down to foil thickness. When formed as a foil, the support is particularly useful in making catalytic converters for automobiles. The formula disclosed shows how aluminum or silicon can be substituted for some of the chromium in the base metal.