Hydrogen exit from metals

Fig. 7. Mercury cathode electroly2er and decomposer (11) 1, brine level 2, metal anodes 3, mercury cathode, flowing along baseplate 4, mercury pump 5, vertical decomposer 6, water feed to decomposer 7, graphite packing, promoting decomposition of sodium amalgam 8, caustic Hquor exit 9, denuded mercury 10, brine feed 11, brine exit 12, hydrogen exit from decomposer 13, chlorine gas space 14, chlorine exit 15, wash water.

One might note the striking similarity between Cases I and II. In both, a crucible failure allowed water to enter and mix with molten titanium. Steam (and hydrogen) formed and the pressure increased so as to bulge the crucible and rupture the safety discs. Tamping the water-metal mix by the fall of the electrode then caused a major explosion. No injuries resulted in the Case II incident because the vault walls provided protection. No data were available to allow an estimation of blast pressures, but as described, the vault construction maintained its integrity and the wave was forced to exit from the bottom. 

Dichloroethane is produced commercially from hydrogen chloride and vinyl chloride at 20—55°C ia the presence of an aluminum, ferric, or 2iac chloride catalyst (8,9). Selectivity is nearly stoichiometric to 1,1-dichloroethane. Small amounts of 1,1,3-tfichlorobutane may be produced. Unreacted vinyl chloride and HCl exit the top of the reactor, and can be recycled or sent to vent recovery systems. The reactor product contains the Lewis acid catalyst and must be separated before distillation. Spent catalyst may be removed from the reaction mixture by contacting with a hydrocarbon or paraffin oil, which precipitates the metal chloride catalyst iato the oil (10). Other iaert Hquids such as sdoxanes and perfluorohydrocarbons have also been used (11). 

Analysis of the exit gas streams from the end of the tubular reactor and from sample ports at various positions on the tubular reactors were made by using a gas-phase chromatographic unit as described earlier (7). This unit was able to analyze routinely all components from hydrogen to C4 hydrocarbons. By increasing the temperatures of the column, qualitative tests also could be made for C5 and C6 hydrocarbons. In the metal reactors, these latter two families of hydrocarbons were not detected. The amount of net coke (the amount of coke that formed and was left on the inner walls of the reactor) was calculated as the difference of the amounts of carbon atoms in the inlet and exit gas streams. Since sample ports in the reactors were used, the amounts of net coke formed tor various path lengths also could be calculated. 

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