| 摘要 |
<p>1348278 Extraction of tin as stannous sulphide vapour PROESA SA 19 April 1971 [7 March 1970] 23570/71 Heading C1A Tin is extracted as SnS vapour from material comprising tin and sulphur values (e.g. ash, slag or matte) by heating the latter (e.g. >1200‹ C.) with an alloy comprising silicon and a transition metal (e.g. iron) to render said material molten, the SnS vapour being evolved from the latter. The amount of alloy is preferably up to 6% by weight of the molten material and said material may be heated together with iron pyrites, anhydrite or gypsum which serve as sources of additional sulphur. A reducing agent (e.g. carbon in the form of coke and/or anthracite) and a flux (e.g. limestone or Al 2 O 3 ) may also be present during the heating and the removal of SnS vapour from the molten materials may be hastened by blowing air over the latter.</p> |
