US814334A - Process of recovering tin or tin and lead. - Google Patents

Description

?ATENTED MAR. 6, 1906.

J. G. TALIAFERRO. PROCESS OF REGOVBRING TIN 0R TIN AND LEAD.

fiPPI-IUATIOE PXLED KARZT. 1985 mvewro {w} ATTORNEYS UNITED STATES JOHN C.

PATENT OFFICE.

TALIAFERRO, OF BALTIMORE, MARYLAND, ASSIGNOR TO CONTI- RENTAL CAN COMPANY,- OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

PROCESS OF REOOVERING TIN OR TIN AND LEAD.

Specification of Letters Patent.

Patented March 6, 1906.

Application filed Karol: 27, 1905. Serial Bot 252,843.

To all whom it may concern.-

Be it known that 1, JOHN C. TALIAFERBO, a citizenof the United States, residing at Baltimore, State of Maryland, have invented a new and useful Improvement in the Processes of Recovering Tin or Tin and Lead, of which the following is a specification.

In the accompanying drawings, which make part of this specification, Figure l-is a front elevation, and Fig. 2 a cross-section, of a furnace suitable for fusing the tin in the mixture; and Fig. 3 shows in vertical section a suitable charcoal-furnace for treating the skimmings.

The purpose of my invention, generally stated, is the separation of tin or tin and lead from a mixture of iron or steel.

The process is peculiarly applicable to the recovery of tin or tin and cad from the mixture of these metals which has been recovered from iron or steel sheets or articles made from iron or steel sheets.

The metallic tin which has been removed from tin-scrap by the electrolytic'process of detinning or by like rocesses is largely amalgamated with the slieet metal or other base which has been coated with tin. Heretofore it has not been practicable to use the tin re-.

moved from scrap-tin, as above stated, for the purpose of makin solder, which is'a mixture of tin and lead a one and which requires to be free, or substantially so, from the presence of iron or other deleterious metal, and for that reason great loss has been sustained by the producers of detinned plate, because the tin owder produced thereby could not he satis actorily refined into pure metallic tin suitable for making solder, but could only be used for textile work or other uses when it has a much less commercial value than the pure pi -tin of commerce. My invention removes t is objectionable feature entirely and restores the pig-tin recovered by the detinning age 0 or other commercial solder, greatly to its value.

The roblem to be solved is how to get rid of the iron or steel. The specific gravity of iron and steel does not vary sufficiently from that of tin to effect a separation based on specific avity. The fusing-point of iron and steel is, however, some 2,500 higher than iron) to pure metallic tin free from iron thereby adding the fusing-point of tin. This fact I utilize and fuse the tin, leaving the iron in suspension therein but unfused. I then effect a me chanical stratification by adding enou h lead to unite with the fused tin, so that t is iron will float to the top of the mixture, where it can be skimmed off. As these skiminings will contain a certain amount of tin and lead, I preferably carry out the process by a further refinement in treating these skimmings to recover the tin or lead. This effects a still further saving; but the main process is quite independent of this subsequent step. When I do, however, save the tin or lead in the skimlnings, I take said skimmings to a charcoalfurnace and fuse the tin or lead therein, which trickles down through the charcoal, while the igoi remains upon the top of the charcoal Obviously my invention can be carried out in a variety of ways and by a variety of structures and the essence of it is as above set forth, and the apparatus described is'purely illustrative.

1 represents any ordinary furnace having a bed 2 and a tap 3. Into this furnace is charged the mixture designed to be purified. The urnace is raised to a temperature high enough to fuse the tin, but leaving the iron in suspension throughout the fused tin. Lead might be added in the furnace; but for convenience I prefer to tap the mixture out into any suitab e vessel, where it is still kept molten, and there add a sufficient percentage of lead as shall by uniting with the tin acuire a sufficient specific gravity to sink to t e bottom of the vessel and float the iron to the top. The iron can readily then be removed by skimming.

In order to save the tin and lead inadvertently caught up in the skimmings, the latter are taken to the charcoal-furnace. (Seen in This is an ordinary upri ht furnace proper pro ortions of tin and lead if not so already an a fine well-refined article of commercial solder is the result.

Having described my invention, I claim- 1. The process of separating tin or tin and lead from iron or steel which consists in fusing the tin or tin and lead, adding suflicient lead to float the iron or steel to the top of the mixture and mechanically removing the alloy.

2. The process of se arating tin or tin and lead from iron or stee which consists in fusing thetin or tin and lead, adding sufficient lead to float the iron or steel to the top of the mixture and skimming off the iron or steel.

, 3. The process of separating tin or tin and lead from iron or steel which consists in fusing the tin or tin and lead, adding sufficient lead to float the iron or steel to the top of the mixture, skimming ofi the iron or steel and separating the tin and load from the iron or JOHN G. TALIAFERRO.

Witnesses:

B. H. LARKIN, BLANOHE A. OULD

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