GB1462056A - Process and apparatus for chemical reactions in the presence of electric discharge - Google Patents

Abstract

1462056 Fluidized bed; treating gases with electrical discharge ELECTRICITY COUNCIL 4 Sept 1974 [7 Sept 1973] 42222/73 Heading H5H [Also in Divisions C6-C7] Chemical reactions are effected at atmospheric pressure by an electric discharge analogous to glow discharge produced in a fluidized bed of particles 11, some of which are non-conducting, the others of which are either of electrically conducting material or have a surface of electrically conducting material, by applying a potential between electrodes 19, 20 across at least a region of the bed, the reactants being introduced into the bed as a gas (e.g. as the fluidizing medium) and/or otherwise (e.g. as a readily vaporized liquid). Fluidized bed 11 has a porous plastics base 13, and a plastics lid 21 with glass lined passages 22 and which supports electrodes 19, 20. Electrodes 19, 20 are arranged, six in an inner ring, twelve in an outer concentric ring such that the distance between adjacent electrodes in each ring is the same and such that each electrode 19 in the inner ring has two electrodes 20 in the outer ring at approximately this same distance. In use each electrode of such a group of three is connected to a different phase of a three-phase supply (4À4 kv.). The bed particles are glass spheres, some coated with copper or silver and of two sizes with ratio of their radii 0À443 : 1 so that in use they tend to form an orthorhombic structure. The conductive particles may be of pure titanium. In preparing pure titanium, titanium tetrachloride liquid is fed to the top of bed 11 from reservoir 16 via valve 17, flow meter 18 and passages 22. Hydrogen is fed in below the bed as the fluidizing medium. Hydrogen leaving the bed is cycled through heat exchangers 28, 29 to condense out titanium tetrachloride vapour, through cold (-18‹ C.) salt water baths 30 to remove hydrogen chloride, over hot wire 36 to scavenge oxygen, pump 38, dryer 39, flow meter 40 back to reactor 10, where the hydrogen is heated by heater 14 to 60‹ C. before re-entering the bed. Topping up hydrogen and initial flushing hydrogen come from reservoir 33. The pressure in the system is maintained by device 41, 42 at more than 55 inches of water above atmospheric.