| 摘要 |
<p>900,698. Producing beryllium by electrolysis. UNITED KINGDOM ATOMIC ENERGY AUTHORITY. July 22, 1960 [Aug. 12, 1959], No. 27637/59. Class 41. Beryllium metal is produced by the electrolysis of a binary anhydrous beryllium chloride/ sodium chloride melt characterized by the step whereby the melt, depleted in BeCl 2 content after electrolysis, is passed down a packed column (e.g. of nickel Lessing rings) in countercurrent flow with BeCl 2 vapour passing up the column so as to enrich the melt with the vapour by direct contact, prior to it being returned to the electrolysis stage. The above step is carried out in the direct contact condenser 6 illustrated in the process diagram of Fig. 1 which uses wet beryllium hydroxide as the starting material. The dried hydroxide is first calcined at 500‹ C. in a fluidized bed using air heated to 800‹ C. as the fluidizing medium, to drive off free and combined water leaving beryllium oxide, which is then mixed with carbon from a hopper 2 and with recycled carbon/BeO debris from pelletising machine 4 in a mixer 3, the C: BeO ratio being adjusted to 1:1. The mixture is formed into pellets by the machine 4 to be charged into a chlorinator 5 in which chlorine gas is passed through a bed of the pellets heated to 800‹ C. to form BeCl 2 vapour and carbon monoxide. The gases from the chlorinator, including excess chlorine, pass (at 500‹ C.) upwards through the condenser 6, down which the BeCl 2 /NaCl melt (depleted in BeCl 2 ) is recirculated at 300‹ C. from a pump tank 7. The melt, enriched by absorbing BeCl 2 , flows out to the tank 7 where it is passed to a purifying electrolytic cell 8 to remove nickel and iron impurities, prior to being pumped to a main electrolytic cell 9 from which depleted melt flows back to tank 7. Beryllium metal is deposited in flake form in the cell 9 on a pure nickel cathode using a carbon anode.</p> |
