| 摘要 |
<p>A residue comprising silicon and silver and/or silver halide, e.g. chloride, which has been employed in the manufacture of organo-substituted halogeno silanes (see Group IV (b)), is heated in a non-oxidizing atmosphere, e.g. hydrogen or nitrogen at above 600 DEG C. up to 1500 DEG C., and thereupon extracted with nitric acid of sp. gr. 1.1-1.5 at say 200 DEG C. Silver chloride may be precipitated from the silver nitrate extract by hydrogen chloride or hydrochloric acid. From 2 to 50 per cent or more of silver may be present in the residue treated. Specification 575,667, [Group IV], also is referred to.ALSO:Relates to the recovery of silver (see Group III) from a residue of contact material employed in the production of organo-substituted halogenosilanes by the passage thereover at an elevated temperature, e.g. above 250 DEG C., of a hydrocarbon halide, e.g. methyl chloride or bromide, ethyl chloride, chloro- or bromobenzene, benzyl or tolyl chloride, &c. The contact mass consists of a mixture of silicon and silver, as in Specification 575,669, [Group III], or of silicon with silver and silver halide, or with silver halide alone. From 2 to 50 per cent or more of silver may be present in the contact material. Specification 575,667 also is referred to.</p> |
