GB1366101A - Apparatus and process for continuously manufacturing whisker crystals - Google Patents

Abstract

1366101 Gas/solid contact apparatus for preparing whisker crystals KANEBO Ltd 19 Oct 1971 [29 Oct 1970] 48485/71 Heading B1F [Also in Divisions Cl and C7] In the preparation of whisker crystals, tubes 2 are selectively introduced via chambers 8, 9 and 10, Figs. 1 and 2, into reacter tube 1 by raising and lowering partitions 11 and 12, where they are periodically pushed along by piston 17 through the centre of furnace 22 where whisker crystals are formed, and the tubes 2 with the contained crystals are selectively discarged via chambers 32, 33 and 34, Figs. 1 and 4, by raising and lowering partitions 35 and 36. Air is purged from the tubes 2 with nitrogen in chamber 9, reactant gas is introduced at 4, and any air in chamber 33 is purged with nitrogen before introducing a tube from chamber 32. Examples describe the preparation of whisker crystals of silicon carbide using fire brick tubes, hydrogen chloride and propane; of copper from copper monoxide and monochloride applied inside the tube and carbon monoxide and carbon dioxide; of silicon nitride from silica and silicon applied inside mullite tubes and hydrogen and ammonia; of silicon carbide from calcium silicate tubes, methyl chloride gas and methane gas; and of silicon carbide from tubes made of silicon/ silica mixture, chlorine and isobutylene.