US971251A - Treatment of ores bearing precious metals. - Google Patents

Description

IJ'NITED smarts PATENT ora ion.

JOHN COLLINS GLANCY, OF NEW YORK, N. Y.

TREATMENT OF ORES BEARING PRECIOUS METALS.

No Drawing.

To all whom it may concern."

Be it known that I, JOHN CoLLINs CLANeY, a subject of the King of Great Britain, having declared my intention of becoming a citizen of the United States, at present residing at New York city, borough of Manhattan, in the county of New York and State of New York, have invented certain new and useful Improvements in the Treatment of Ores Bearing Precious Metals, of which the following is a specification.

My invention relates to a novel method of treating ores bearing the precious metals, which method is particularly described and pointed out in the following specifications and claims.

I have discovered that the precious metals may be advantageously recovered from ores containing them, whether such ores be rebellious or non-rebellious, by the use of a cyanid solution containing a soluble iodid and nitrogen oxids. In the case of rebellious ores those containing, for example, reducing agents, or tellurium, orbothno preliminary treatment, such as roasting, is required.

In carrying my invention into practice, effecting the solution of the precious metals, whether reducing agents and tellurium be or be not present, I treat the pulverized ore simultaneously with a cyanid solution-such, for example, as potassium cyanidiodin or a soluble iodidsuch, for example, as potassium iodidand nitrogen 0xidssuch, for example, as nitrogen peroxid. In practice with certain ores I have treated, I have found the following proportions to answer well the purposes of the process: a solution of one pound of potassium cyanid, one-half pound potassium iodid, and one-half pound of lime or soda, dissolved in two thousand pounds of water in the proportion of two parts of said solution to one part of ore. The amount of nitrogen peroxid to be passed into the solutionwith or without the admixture of airis to be determined by titration, or otherwise. In practice I have found that a proportion equivalent to two hundred grams of nitrogen peroxid to two thousand pounds of solution gave good results, although with some ores as little as fifteen grams of nitrogen peroxid to two thousand pounds of solu- Specification of Letters Patent.

Application filed February 2, 1909.

Patented Sept. 2'7, 1910.

Serial No. 475,664.

tion have given excellent results. The solution may be alkaline, or neutral, or only slightly acid. The same solution can be used again and again by keeping up the requisite strength in cyanid and nitrogen peroxid, but no further addition of potassium iodid is necessary, except to compensate for mechanical losses, as the nitrogen peroxid regenerates the iodin to begin its work over again. Between each operation it is desirable to pass the liquor through Zinc-shavings in the ordinary way to extract the values which it contains.

As I have said, it is not necessary in practicing the above processes with rebellious oresthose containing, for example, reducing agents (sulfids of iron, etc.) or tellurium, or bothto roast the ore, since the sulfids do not act on the solution to decompose it, and the tellurium is dissolved simul taneously with the precious metal.

Instead of applying said nitrogen peroxid to the solution in the presence of the ore being treated, it might be, although less advantageously, applied to the solution after it has been separated from the ore, or between successive treatments of ore, since its function is to regenerate the iodin and this function might be performed otherwise than in the presence of ore being treated.

The cost of iodin in a commercial process would be prohibitive were it not for the fact that in the processes above described the iodin is repeatedly regeneratedand does the same work over and over again. Its action may be likened to that of a vehicle or car rier and hence it is not substantially consumed.

It will be understood that various modifications and changes in the described process may be made without departing from the spirit of my invention and without exceeding the scope of my claims.

In a pending application Serial No. H5562 I have described the above process as an example, among others, of a generic invention, but I have not claimed it therein specifically. I do not claim in this patent the said generic invention, but

IVhat I claim specifically herein is 1. The process of treating pulverized ore containing precious metals which consists in subjecting the ore to the action of a cyanicl solution, asoluble ioclicl and nitrogen oxicl.

2. The process of treating pulverized ore containing precious metals Which consists in subjecting the ore to the action of a cyanicl solution, a soluble ioclid and nitrogen per oxid.

In testimony whereof I have signed my name to thls specification 1n the presence of 10 tWo subscribing wltnesses.

JOHN COLLINS OLANOY.

Witnesses M. GOLDBURG, M. H. HARDING, J r.