Patent GB-504395-A (GB)
Title: Improvements in or relating to processes of concentrating non-metallic minerals fromores containing silicious matter
IPC: B03D1/01
Filed: 1937-10-27
Abstract: 504,395. Concentrating ores. PHOSPHATE RECOVERY CORPORATION. Oct. 27, 1937, No. 29356. Convention date, July 28. [Class 82 (ii)] [Also in Group IV] Alkaline earth metal minerals which do not contain silica, e.g. calcite, fluorspar, barytes, and calcium phosphates, are separated from siliceous matter by adding to an aqueous pulp of the ore certain amine compounds containing water-repellent hydrocarbon groups which act as collecting agents for one of the constituents and then separating this constituent, e.g. by froth flotation or tabling. The amine compounds are either free amines or salts of amines and acids of substantial solubility in water, e.g. sulphuric, hydrochloric, or acetic acid. The water-repellent group is normally a straight chain aliphatic radical of more than 5 and preferably of at least 8 carbon atoms, but the compound used may be a resin-amine produced by condensation of an aldehyde with an aromatic amine such as a toluidine in the presence of a reactive substance which will yield a water-repellent group, and in compounds of this class the water-repellent group may be either aliphatic or aromatic. For example, the reactive substance used in the preparation may be a hydrocarbon containing an unsaturated straight chain of more than 5 carbon atoms, an ester of a fatty acid containing such a chain, mixtures containing these compounds such as fuel oil or linseed oil, a cyclic hydrocarbon such as naphthene or abietene, compounds such as naphthenic or abietic acid, or substances containing the phenyl nucleus such as benzaldehyde. Examples are given of the preparation of resin-amines or resin-amine salts by reaction between orthotoluidine, formaldehyde, hydrochloric acid, and either fuel oil, linseed oil, naphthenic acid, an oil containing abietic acid known as Nelioresin, retene, or benzaldehyde. The products are dissolved in butanol for use in the separation process. The aliphatic amines used may be primary, secondary, tertiary, or quaternary and the amine radical may be connected directly or indirectly to the hydrocarbon radical; e.g. it may be connected through an altered carboxyl group, the compound being formed by reaction between an organic acid and an aminoalcohol, e.g. oleic acid and triethanolamine, or between an alcohol and an amino acid, the acid and alcohol in the respective cases containing, the water repellent group. Any amine soaps formed are removed if the siliceous constituent is to be collected. A quaternary amine compound containing cetyl and stearyl chloride acetate may be prepared by esterifying a mixture of cetyl and oleyl alcohols with chloroaoetic acid and heating the product with pyridine. The collectors may be added to concentrated or diluted pulp and may be used in conjunction with other reagents. In concentrating phosphate ores, the siliceous material may be first floated with one of the amine compounds and the phosphate residue then floated, for example, with caustic soda, fuel oil, fish acid, and kerosene-rosin frother. Numerous examples are given of the flotation of silica from calcium phosphate, using resin-amine compounds or amines such as octadecylamine or octadecyleneamine or their salts either alone, in solution in kerosene, warm water, alcohol, alcohol-benzene mixtures, or in conjunction with other reagents such as pine oil, fuel oil, caustic soda, or concentrated sulphuric acid. Examples are also given of the flotation of siliceous material from limestone, of the flotation of barytes from silicates and of silicates from barytes, of the flotation of fluorspar from silica and calcite, and of silica and fluorspar from calcite. Specifications 410,956 and 463,261 are referred to.