US2393239A - Refining of nonferrous metals - Google Patents

Description

Patented Jan. 22, 1946 REFINING or NONFERROUS METALS Louis S. Deitz, Jr., 'Westiield, N. 3., assignor to Nassau smelting & Refining Company, Incorporated, New York, N. Y., a corporation of New York No Drawing. Application January 9, 1942,

Serial No. 426,168

6 Claims. (CL 204-120) This invention relates to the refining of nonferrous metals and more particularly to the electrolytic refining of non-ferrous metals consisting principally of lead and/or tin and containin copper and antimony.

At present there is a considerable quantity of metal on the market containing principally tin, lead, copper and antimony inwhich the copper and antimony together comprise more than 8% of' the metal; There is no method now in general use by which the above-mentioned metal can be electrolytically refined on a commercial basis.

A sulphonic acid electrolyte such as is disclosed .in Patent 2,286,240, granted June 16, 1942, to

J. R. Stack for Refining of non-ferrous metals, will operate successfully to refineanodes made of alloys consisting principally of tin and lead when the anode metal contains relatively small amounts of copper and antimony. However, when electrolyzed in asulphonic acid electrolyte of the type disclosed in that patent, anodes consisting mostly of tin and lead and containing more than 8% of copper and antimony together tend to polarize and may require an excessive voltage to dissolve invention relates particularly to metal such as that mentioned above, wherein the copper and antimony together comprise more than about 8% and not more than about 15% of the metal, it is understood that similar metal containing less than 8% copper plus antimon in admixture can be successfully treated in applicant's electrolyte.

One lot ofanodes treated according to theabove-described embodiment of the invention analyzed before treatment:

. Per cent Copper 5 Tin 18 Lead 12 Antimony 5 The electrolyte, in this specific embodiment of the invention, contains from about 200 to about 250 grams per liter of free benzene di-sulphonic acid and from about 3 to about 5 grams per liter of hydrochloric acid. Generally, from about to about 40 grams per liter oi tin and from about 5 to about 10 grams per liter of lead in the form of their benzene di-sulphonates are in solution in Objects of this invention are to provide new and improved electrolytes for electrolyticallyrefining non-ferrous metals and to provide new and improved processes for electrolytically refining non-ferrous metals.

Further objects and features of the invention will be more apparent from the following detailed description.

In general the-invention comprises a process for refining metal consisting principally of metal of the group consisting of tin, lead, copper and antimony, wherein the copper and antimony taken together comprise more than about 8% and not more than about 15% of the metal. This process 1 comprises making anodes oi such metal and electrolyzing the anodes in an electrolyte consisting benzene di-s'ulphonic acid. Also, the concentration of the sulphonic acid in solution may be zene di-sulphonate salts.

the electrolyte. The tin and lead may be elec-- trolytically dissolved in the sulphonic acid electrolyte or may be added in the form of their ben- The temperature of the cell is kept between 50 .to 55 C. and the current density may vary from 8 to 16 amperes per square foot with the voltage at .35 to .45 volts. Addition agents, such as glue, 4.4 lbs., and beta naphthol, 2.2 lbs., per ton of cathodes, or any equivalents thereof, may-be added in order to improve the quality oi the cathodes formed.

After electrolysis the cathodes consisting of 84.2% tin and 15.8% lead, were melted down to form pigs for solder adjustment.

The anode slimes contained:

Per cent Copper 18.2 Tin 54.6 Lead 1.0 Antimony 18.2

These slimes were further'treated to form Babbitt metal.

It is apparent that the invention is susceptible of considerable variations from the specific embodiment described above. For example, other aromatic sulphonic acids, such as phenol sulphonic acid or its equivalent, or mixtures of arcmatic sulphonic acids, may be used in place of varied to suit the type of metal and the electrolytic conditions desired. Thus, either benzene di-sulper liter of hydrochloric acid to prevent polarization of the anodes, whereby tin and lead are deposited at the cathode.

3. The method of separating metals from metallic materials consisting principally of tin and lead and containing at least about 8% but not A more than about 15% of copper and antimony,

solution to produce chloride ions, can be used in place of hydrochloric acid. If a salt such as sodium chloride is used, steps must be taken to remove the sodium cations to prevent them from building up and interferring with the platingoperation.

The temperature and current density may likewise be varied to meet changing conditions. ,The addition agents may be any of those generally used for the purpose of improving the quality of the cathodes produced. Other changes which are within the spirit of the invention will be apparent to those skilled in the art.

While the benzene di-sulph'onic acid employed may be any one or more of the three isomers of this acid, it has been found that successful results may be obtained by using a commercially obtainable acid which consists principally of metabenzene di-sulphonic acid, but which contains variable amounts of the para and ortho forms. The phenol sulphonic acid employed may be the purified product of the direct sulphonation of phenol containing a mixture of mono-sulphonated and di-sulphonated phenol with perhaps small amounts of even higher sulphonation products.

What is claimed is:

1. The method of separating metals from metallic materials consisting principally of tin and lead and containing at least about 8% but not more than about of copper and antimony, which comprises forming anodes of such a material, and electrolyzing the anodes in a bath consisting of a water solution of tree aromatic sulphonic acid and aromatic sulphonic acid salts of tin and lead, in which the tota1 acid in free, and combined forms is from about 75 to about 600 grams per liter and which contains from about 3 to about 5 grams per liter of hydrochloric acid to prevent passivity of the anodes, whereby tin and lead are deposited at the cathode.

2. The method of refining metallic materials consisting principally of tin and lead and containing copper and antimony which aggregate from about 8% to about 15% of the materials.

which comprises electrolyzing anodes of such a material in an electrolyte consisting of a water solution of an aromatic sulphonic acid and aromatic sulphonic acid salts of tin and lead, in which the total acid in free and combined forms is from about 150 to about 400 grams per liter and which contains from about 3 to about 5 grams which comprises forming anodes of such a material, and electrolyzing the anodes in a bath consisting of a water solution of free benzene disulphonic acid and benzene di-sulphonic acid salts of tin and'lead, in which the total acid in free and combined forms is from about 75 to about 600 grams per liter and which contains from about 3 to about 5 grams per liter of hydrochloric acid to prevent polarization of the anodes, whereby tin and lead are deposited at the cathode.

4. The method of separating metals from metallic materials consisting principally of tin and leadand at least about 8% but not more than about 15% of copper and antimony, which comprises iorming anodes of such a material, and eiectrolyzing the anodes in a bath consisting of a water solution of free phenol sulphonic acid and phenol sulphonic acid alts of tin and lead, in which the total acid in free and combined forms is from about '75 to about 600 grams per liter and which contains from about 3 to about 5 grams per liter of hydrochloric acid to prevent polarization of the anodes, whereby tin and lead are deposited at the cathode.

5. The method of refining metallic materials consisting principally of tin and lead and containing copper and antimony .which aggregate from about 8% to about 15% of the materials, which comprises electrolyzing anodes of such a material in, an electrolyte consisting of a water solution of free benzene di-sulphonic acid and benzene di-sulphonic acid salts ot'tin and lead, in which the total acid in free and. combined forms is from about to 400 grams per liter and which contains from about 3 to about 5 grams per liter of hydrochloric acid to prevent polarization of the anodes, whereby tin and lead are deposited at the cathode.

6. The method of refining metallic materials consisting principally of tin and lead and containing copper and antimony which aggregate from about 8% to about 15% of the materials, which comprises electrolyzing anodes of such a material in an electrolyte consisting of a water solution of free phenol sulphonic acid and phenol sulphonic acid salts of tin and lead, in which the total acid in tree and combined forms is from about 150 to about 400 grams per liter and which contains from about 3 to about 5 grams per liter of hydrochloric acid to prevent polarization of the anodes, whereby tin and lead are deposited at the cathode.

- LOUIS S. DEITZ, JR.

Certificate of Correction Patent No. 2,393,239. January 22, 1946. LOUIS S. DEITZ, JR.

It is hereby certified that error appears in the tinted epecification of the above numbered atent requiring eorreetion'ae follows: ago 2, second column, line 20, claim 4, ter the words lead and" insert containing' and that the said Letters Patent should be read with this eorrection therein that t a same may coniorm to the record of the ease in the Patent Ofliee.

Signed and sealed this 14th day of May, A. D; 1946.

[amt] IESLIE FRAZER, First Assistant Gmnmissiener of Patents.