Perforated platinum foil

The interior of the furnace was lined with platinum foil to limit any reaction of the oxide vapors with the alumina furnace walls. Three perforated platinum foil diaphragms were placed at intervals inside the furnace to act as heat shields and to ensure thorough mixing of the oxide vapor-air mixtures. 

The cylindrical separatory funnel A has a volume of 1200 cc. and holds 2 kg. (15.75 gram atoms) of iodine crystals (Note 2). A piece of perforated platinum foil B, or a loose plug of glass wool, is placed in the bottom to prevent clogging of the stopcock by iodine crystals or solid impurities. Stopcock C is as large as 5 mm. in bore as a further precaution. For the production of up to 4 kg. of methyl iodide, a 5-I. round-bottomed Pyrex flask D is used (Note 3). It is partly submerged in a water bath. Tube E, fitted into the reaction flask by a rubber stopper, is at least 2.5 cm. in internal diameter in order to allow the vapor to rise without interrupting the return of the excess distillate. Tube F is 4 cm. in diameter to allow for preliminary condensation. A space (13 cm.) is left above stopcock G as a reservoir for the distillate. Stopcock G has a bore of 2 or 3 mm. (Note 4). The bottom of the tube from this stopcock is flush with the bottom of the rubber stopper to the iodine container, so that thok ... 

Eight platinum anodes are suspended in the anode space, having on one side or both sides a foil of smooth platinum 5 (0.05 min thick, 8 mm wide and 350 mm long). Each foil is welded to platinum wires which arc soldered on the copper rods 4 through wliioh the current is conducted to the anode. Against the corrosion effect of the anolyte the copper rods are protected with a coating of rubber. The cathodes made of perforated lead sheets 6 and lead coil 7 to cool the catholyte are placed in the cathode space. Usually the lead coil is welded to the cathodes. 

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