This invention discloses a portable catalytic combustion heater. Fuel
vapor and air are supplied to a catalyst which promotes the flameless
combustion of the fuel, releasing heat. The fuel is supplied as a liquid,
passes through a selectively permeable membrane such that fuel vapor
exits the membrane and is fed to the catalyst. Additional features such
as porous supports and means of enhancing and diminishing the catalytic
rate of combustion and controlling the heat output are also shown. This
invention can be used to heat apparel, blankets, food, dwellings,
containers, machinery, insect attractants, humidifiers, and perfume
generators.