A process of phosphate flotation comprising: pulping phosphate ore with water to about 55% to 75% solids to produce an ore slurry; conditioning the ore slurry with a new reagent scheme to produce a conditioned slurry; subjecting the conditioned slurry to flotation to produce an underflow and an overflow; and collecting the overflow as phosphate concentrate. The new reagent scheme may comprise a combination of fatty acid, fuel oil, and fatty acid soap, and may not comprise a pH modifier. The process may also work effectively at a lower percent solids than conventional reagent schemes.

A method of making porous ceramic granules is provided. The method comprises heating pore-forming agent particles to a temperature above a glass transition temperature for the pore-forming agent particles; contacting the heated pore-forming agent particles with a ceramic material to form a mixture of pore-forming agent particles and ceramic material; heating the mixture to remove the pore-forming agent particles from the mixture to form a porous ceramic material; and micronizing the porous ceramic material to obtain the porous ceramic granules, wherein the porous ceramic granules have an average diameter from about 50 m to 800 m. The porous ceramic granules are also disclosed.

A method for producing calcium phosphate by the present invention is characterized by comprising the steps of: (a) preparing a 0.5-1.5 M aqueous calcium salt solution, a 0.3-0.8 M aqueous phosphate solution, and a 0.1-0.5 M aqueous carbonate solution; (b) mixing the aqueous phosphate solution and the aqueous carbonate solution in step (a) to prepare a mixture solution; (c) adding an aqueous alkaline solution to the aqueous calcium salt solution in step (a); (d) adding an aqueous alkaline solution to the mixture solution in step (b); (e) mixing and reacting the aqueous calcium salt solution with the aqueous alkaline solution added thereto in step (c) and the mixture solution with the aqueous alkaline solution added thereto in step (d) to prepare a precipitate; and (f) filtering, washing, and drying the precipitate in step (e) to obtain calcium phosphate, wherein the primary particle size of the calcium phosphate is 100 nm or smaller and the specific surface area thereof is 40-150 m2/g.

The object of this invention is to provide a method of mineral flotation using bioreagents extracted from Gram positive bacteria Rhodococcus opacus and Rhodococcus erythropolis. In this sense, mineral floatability was evaluated using bioreagent extracted from Gram positive bacteria to determine its potential as an alternative to synthetic reagents and also an alternative to the use of microorganisms themselves (biomass).

The present invention provides that powder is mainly constituted from secondary particles of hydroxyapatite. The secondary particles are obtained by drying a slurry containing primary particles of hydroxyapatite and aggregates thereof and granulating the primary particles and the aggregates. A bulk density of the powder is 0.65 g/mL or more and a specific surface area of the secondary particles is 70 m.sup.2/g or more. The powder of the present invention has high strength and is capable of exhibiting superior adsorption capability when it is used for an adsorbent an adsorption apparatus has.

In order to provide a film-forming powder using hydroxyapatite which is a main component of teeth, or hydroxyapatite in which a color tone adjuster is blended, the powder being used in a jet-device for forming a film on a surface of a tooth by spraying the powder on the tooth, and being suitable for forming a film having a high hardness and extremely low solubility in acid in a short period of time, and suitable for forming a film of a powder conforming to the color tone of a tooth in a short period of time; a hydroxyapatite powder calcined in an inert gas atmosphere at 600 to 1350 C., a powder obtained by applying to the hydroxyapatite powder calcined at 600 to 1350 C. plasma irradiation, or plasma irradiation and mechanical energy, and additionally a film-forming powders obtained by blending color tone adjusters into these hydroxyapatite powders are produced.

The present invention relates to a permanently polarized hydroxyapatite and a composition or material comprising thereof. The present invention further relates to a process for obtaining a permanently polarized hydroxyapatite and to different uses of the permanently polarized hydroxyapatite or the composition or material comprising thereof.

Process of acid attack with sulphuric acid of a phosphate source comprising calcium or not comprising calcium for a predetermined time period ranging from 20 to 180 minutes in the conditions wherein the molar ratio of sulphate from the sulphuric acid and possibly from the phosphate source to the calcium present in the phosphate source ranges from 0.6 to 0.8, and the content in P.sub.2O.sub.5 in the attack tank is of less than 6%.

A method of producing a product inorganic compound including: immersing a raw material inorganic compound having a volume of 10.sup.13 m.sup.3 or more in an electrolyte aqueous solution or an electrolyte suspension; exchanging anions in the raw material inorganic compound with anions in the electrolyte aqueous solution or the electrolyte suspension; cations in the raw material inorganic compound are exchanged with cations in the electrolyte aqueous solution or the electrolyte suspension; or including a component (that excludes water, hydrogen, and oxygen) in the electrolyte aqueous solution or the electrolyte suspension not included in the raw material inorganic compound in the raw material inorganic compound; and obtaining a product inorganic compound having a volume of 10.sup.13 m.sup.3 or more from the raw material inorganic compound.

The present invention provides that powder is mainly constituted from secondary particles of hydroxyapatite. The secondary particles are obtained by drying a slurry containing primary particles of hydroxyapatite and aggregates thereof and granulating the primary particles and the aggregates. A bulk density of the powder is 0.65 g/mL or more and a specific surface area of the secondary particles is 70 m.sup.2/g or more. The powder of the present invention has high strength and is capable of exhibiting superior adsorption capability when it is used for an adsorbent an adsorption apparatus has.