US1677416A - Buknell b - Google Patents

Description

Patented July 17, 1928.

UNITED STATES PATENT OFFICE.

BURNELL R. TUNISON, F ELIZABETH, NElV JERSEY.

ORE CONCENTRATION.

NoDrawing. Application filed February This invention consists of improvements in processes ofore COUCQlll'lzltlOl'l, andhas particular reference to ore concentration by flotation- In these processes the powdered ore is usually mixed with water, such mixture being termed the pulp, and to this pulp added the flotation agent, consisting of an oil or oils, or a frothing agent or agents, or both, and thepulp is'then subjected to agil0 tation and aeration; for example, supraaeration by air introduced from above by beating it into the pulp, or by subaeration by air introduced from below through a po' rous medium or otherwise. As well known in the art, the result of this aeration is that the air bubbles coursing through the pulp gather up the metalliferous particles and carry them to the surface where they form a froth. This froth may be readily floated over a lip or dam and will thus carry the metalliferous particles away from the body of the liquid. In these processes a mineral acid, such as sulfuric acid, is in some instances used in addition to the frothing agent, and in other instances an alkali is used in addition to the frothing agent, and these additional substances, acid or alkaline, act in some manner not clearly understood to modify the properties of the liquid or ore and to assist the flotation of the nietalliferous mineral and to retard or prevent the flotation of the gangue.

This invention relates specifically to the process of ore concentration by the use of oils containing sulfur compounds, many of them quite complex in their constitution, which oils have unusual and valuable coating, flocculating, and in many instances frothing and sulfldizing properties. These oils may be obtained from petroleum and its products, shale oil and its products, coal tar and its products, still gases and residues, oxidized oils, wood oils etc., by treating them substantially as described in my co-pending application Serial No. 691,811 entitled Flotation agents and process of producing same, filed on February 9, 1924.

As disclosed in my said co-pending application the flotation agent may be produced from the above named materials, by washing the material with alkali, for instance, with a solution of caustic soda, with agitation and allowing the mixture to settle. The mixture will become stratified into an alkali layer and an oil layer. The alkali layer, however, contains some oil, and particularly oil con- 9, 1924. Serial No. 691,810.

twining sulfur compounds. This oil is then extracted from the alkali layer either by adding an acid, for instance, sulfuric acid, to neutralize the removed. alkali layer, which will cause the oil to separate out that it can be removed physically, or the oil may be taken up with a solvent, for instance, benzol, and ren'iovcd therewith, and recovered from the solvent by distilling the solvent away. Preferably, thereafter the oil is washed. The alkali above referred to may he a 18-24? gravity caustic soda solution, and theacid may be sulfuric acid of 90-98% strength, although my process is not limited to these specific elements or strengths, and may be carried out by the use of an alkali other than caustic soda, and the alkali treatment may be made either preceding or subsequent to an acid treatment, usually sulfuric acid, as carried out in petroleum refinin An exceptionally good flotation agent is produced by treating apetroleum distillate, for instance, naphtha, in the above manner.

Several types of ores may be very successfully concentrated by flotation by means of this invention. Sulfide ores, for example, chalcocitc, chalcopyritc, galena, and sphalerite, and the like with the siliceous ganguc may be treated by flotation, and the separation of the metalliferous products from the ganguc is much more complete by means of this process. Oxidized ores such as malachite, azuritc, and cerussite have been successfully treated by means of this process. In cases where sulfidizing agents are at present used in practice, the use of this process permits a marked reduction in the quantity of sulfidizing agent necessary. In the use of these sulfidized oils, the quantity necessary will vary materially with the type and quality of the ore to be treated. Sulfide ores usually require from one-half pound, orless, to two pounds per ton of ore treated. hen an ore difficult of flotation is to be used. such as mixed oxidized and sulfide ma terial, or some of the low grade porphyries, a quantity of oil up to four or five pounds per ton may be necessary. 111 cases where a sulfidizing agent such as sodium sulfide is used in practice, the use of this invention will. make possible a considerable reduction in the quantity of sulfldizing agent necessary.

In using this invention, the flotation materials may be added to the ore alone or in admixture with other agents promoting the flotation, in any suitable n'ianner, so that they Will be thoroughly and uniformly distributed throughout the ore pulp. In applying the materials they may be introduced into the tube mill in which the ore is being ground or they may be otherwiseintroduced into the ore pulp in any suitable Way.

What I claim is 1. A process of efliecting the concentration of minerals by froth flotation, which comprises subjecting to froth flotation a mineral pulp in the presence of the extracted oily sulturous component of a sulfurous petroleum oil, said extracted component being soluble in caustic and insoluble in Water.

,2. A process of effecting the concentration of minerals by froth flotation, which com prises subjecting to froth flotation a mineral pulp in the presence of a sulfurous oil extracted from an alkali solution of constituents of a distillate of a sulfurous petroleum oil.

3. A process of effecting the concentration of minerals by froth flotation, which oomprises subjecting to froth flotation a mineral pulp in the presence of a sulfurous oil extracted as such from the alkali layer formed pulp in the presence of a sulfurous oil ex-' tracted as such from the alkali layer formed upon mixing caustic soda with a cllstillate of a sulturous petroleum Oll.

This specification signed this 12th day of May, 1925. I I 'BURNELE R. 'TUNISON.