| 摘要 |
PROCESS FOR PREPARATION OF SILANE of the Invention A process for continuously preparing silane and a coproduct by reacting a metal hydride such as NaAlH4 with a silicon halide such as SiF4, utilizing, in conducting the reaction, equipment which includes, in series, a primary reactor, a secondary reactor and a separation zone. The metal hydride is reacted in the first reactor with less than a stoichiometric amount of the silicon halide, and the unreacted metal hydride is then passed to the second reactor wherein the remainder of the hydride is reacted in the secondary reactor, in which a stoichiometric excess of the silicon halide is added. The rate of silicon halide or metal hydride addition is governed by a temperature differential feedback from the reaction in the secondary reactor so that overall a stoichiometric or substantially stoichiometric operation is achieved. Techniques are also disclosed for splitting the silicon halide feed between the liquid and vapor phases of the secondary reactor to eliminate the hazard of combustible mixtures, and, with variable speed agitation of the liquid, to control the mass transfer characteristics of the reaction. Also, consistent kinetics result from control of residence time by varying the liquid level in the secondary reactor as related to the halide or hydride mass flow rates. These improvements conserve resources, provide improved coproduct and reduce costs.
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