Chemically contaminated air is to be purified and/or detoxified by catalytic oxidation in an integral heat exchanger and reactor. This device of a double spiral is made by winding together two strips of metal coatewd with a catalyst. One spiral passage leads into the core of the spiral and the other passage leads out. An electrical-resistance heater supplies energy at the core of the spiral. The outflowing air transfers this heat to the inflowing air through the walls of the spiral, thus minimizing the required heat input for a specified core-temperature. Owing to the heat exchange the core-temperature-elevation may be many times the temperature-elevation in the existing air. The objective of the research is to investigate the rates of heat transfer, catalytic reaction and heat loss, and to determine the necessary surface are, apacing, heat input, core temperature, etc., for representative contaminants.