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Vapor phase reduction of boron trichloride with hydrogen on electrically heated filaments in flow systems was investigated as a potential method for the preparation of high-purity boron. Experiments were conducted on laboratory and bench-scale flow reactors. Conversion efficiency was a function of mole ratio of reactants, residence time, mass of deposit, and deposition temperature.Massive deposits of crystalline boron analyzing as high as 99.6% by direct chemical analyses were obtained. Purity of boron appeared to be a function of both filament diffusion and boron trichloride purity. Titanium filaments were found to be most satisfactory, since contamination due to titanium could be removed by chlorination at 300~ X-ray diffraction studies indicated that titanium probably existed in solid solution with boron rather than as a boride.

Lead dioxide was investigated as an anode substitute for platinum in the production of sodium perchlorate. Rod shaped deposits were prepared on nickel and platinum clad tantalum wires. The plate was dense, heavy, metallic‐like in appearance and not too fragile for ordinary handling. The first phase of experimentation was performed in small laboratory cells to determine approximate electrolyses data. Larger bench‐scale production cells were also run simulating plant operating conditions. Lead dioxide anodes produce sodium perchlorate at high cumulative current efficiencies. One lead dioxide anode was used in cell operation for 3,000 hr. Cumulative current efficiency for a given anodic current density is a function of the cathode material, cathodic current density, and the additive used. Perchlorate can be produced using nickel, copper, stainless steel, and carbon steel cathodes. Energy requirements, under identical experimental conditions, indicate that stainless steel and nickel are the best cathode materials. A current efficiency of 91.5% was obtained with a stainless cathode at anodic and cathodic current densities of 15.5 amp/dm2 and of 7.25 amp/dm2, respectively. No unusual metallic contamination could be detected in the ammonium perchlorate prepared from the sodium perchlorate.