DIVISION OF ENGINEERING: CHEMICAL REACTIONS IN THE PLASMA JET*

Abstract

Chemistry at extremely high temperatures, especially of ionized gases, or plasma, is discussed. As an example, the properties of nitrogen at atmospheric pressure at temperatures from about 3000 deg to 25000 deg K are described. Methods for generating a plasma at 15000 deg K at atmospheric pressure are outlined and illustrated by use of an open electric arc for which the temperature ordinarily varies from 6000 to 8000 deg K. The production and characteristics of the plasma jet are explained, with reference to a small commercial plasma jet of 40-kw capacity. Applications of the plasma jet principle, particularly for the production of acetylene, are discussed. In a survey of possible plasma jet applications where the price of heat is that of electricity, molecules with atoms of high atomic weight will be most promising. The use of extremely fast cooling rates in a plasma to make very finely divided nickel powder by the thermal decomposition of nickel carbonyl are described. The so-called intermediate section plasma jet reactor is described and discussed in detail. Preliminary results of experiments in a nitrogen plasma that take advantage of the rapid temperature drop experienced by the effluent plasma to freeze and determine the equilibrium populationmore » of atomic species are reported. When methane is fed to the nitrogen jet, it is rapidly converted to C/sub 2/ and precursors at the high temperatures involved. When these collide with nitrogen atoms or ions, CN radicals should form, which in the cooler portions of the jet combine with hydrogen to form HCN. (BBB)« less