Abstract: Catalysts having as their active component sulfides of vanadium, molybdenum and tungsten are contacted with ammonia or with an amine which in aqueous solution has a basic ionization constant greater than that of ammonium hydroxide to suppress deactivation of the catalysts by exposure to the atmosphere.

Abstract: A gas phase process for the regeneration and concentration of spent sulfuric acid containing oxidizable impurities, which minimizes decomposition of sulfur trioxide to sulfur dioxide comprising: providing one or more reactor vessels containing hot turbulent combustion products; providing a supply of oxygen to the reactor; atomizing into the reactor vessel or vessels the spent sulfuric acid in droplets capable of evaporating in less than several milliseconds whether or not electromagnetic or ultrasonic energy sources are used to augment evaporation, having a particle size smaller than 50 microns, thereby vaporizing the droplets, almost instantaneously, dissociating the spent sulfuric acid into sulfur trioxide and water, and oxidizing the hydrocarbons; maintaining the temperature in the reactor vessel below 1000.degree. C.