The invention is related to a flotation process using an improved collector to remove alkaline earth metal carbonate impurities from phosphate ores. The flotation feed may be conditioned with the improved carbonate collector at acidic pH, and subjected to a reverse flotation. The cell overflow may be collected as waste in which carbonate minerals dominate, and the cell underflow may be the phosphate concentrate. The collector may be a combination of chemicals, comprising: (1) any kind of fatty acids, either conventional fatty acid, saponified fatty acid, or modified fatty acid; (2) chemicals with sulfonate or sulfate groups, such as dodecylbenzene sulfonic acid (DDBSA) or its salt, sodium dodecyl sulfate (SDS), sodium lauryl sulfate (SLS), sodium coco sulfate (SCS), etc.; and (3) phosphorous-bearing chemicals, such as sodium tripolyphosphate (STPP), sodium hexametaphosphate (SFMP), trisodium phosphate (TSP), Tetrasodiumpyrophosphate (TSPP), etc. With the improved collector, the separation selectivity and phosphate recovery may be significantly improved.

The invention is related to a flotation process using an improved collector to remove alkaline earth metal carbonate impurities from phosphate ores. The flotation feed may be conditioned with the improved carbonate collector at acidic pH, and subjected to a reverse flotation. The cell overflow may be collected as waste in which carbonate minerals dominate, and the cell underflow may be the phosphate concentrate. The collector may be a combination of chemicals, comprising: (1) any kind of fatty acids, either conventional fatty acid, saponified fatty acid, or modified fatty acid; (2) chemicals with sulfonate or sulfate groups, such as dodecylbenzene sulfonic acid (DDBSA) or its salt, sodium dodecyl sulfate (SDS), sodium lauryl sulfate (SLS), sodium coco sulfate (SCS), etc.; and (3) phosphorous-bearing chemicals, such as sodium tripolyphosphate (STPP), sodium hexametaphosphate (SFMP), trisodium phosphate (TSP), Tetrasodiumpyrophosphate (TSPP), etc. With the improved collector, the separation selectivity and phosphate recovery may be significantly improved.

Provided herein are systems and methods for producing nitrophosphates and mineralized carbon. Advantageously, the systems and methods are capable of sequestering carbon from the atmosphere. The systems generally include a first reactor for producing nitric acid; a mixer for mixing the nitric acid produced in the first reactor with a phosphate source, thereby producing nitro-phosphoric acid; and a second reactor for producing a solution comprising nitrophosphates and mineralized carbon, wherein the second reactor is operable to receive: the nitro-phosphoric acid from the mixer, ammonia, water, and carbon dioxide.

A method for preparing a metal-free few-layer phosphorous nanomaterial. The method comprises an ice-assisted exfoliation process (or solvent ice-assisted exfoliation process). The method allows for the preparation of a few-layer phosphorous nanomaterial with improved yield and reduced duration and exfoliation power. The few-layer phosphorous nanomaterial is used in the preparation of a photocatalyst. The photocatalyst exhibits a long-term stability, high photocatalytic H.sub.2 evolution efficiency from water, and good stability under visible light irradiation.

The invention is related to a flotation process using an improved collector to remove alkaline earth metal carbonate impurities from phosphate ores. The flotation feed may be conditioned with the improved carbonate collector at acidic pH, and subjected to a reverse flotation. The cell overflow may be collected as waste in which carbonate minerals dominate, and the cell underflow may be the phosphate concentrate. The collector may be a combination of chemicals, comprising: (1) any kind of fatty acids, either conventional fatty acid, saponified fatty acid, or modified fatty acid; (2) chemicals with sulfonate or sulfate groups, such as dodecylbenzene sulfonic acid (DDBSA) or its salt, sodium dodecyl sulfate (SDS), sodium lauryl sulfate (SLS), sodium coco sulfate (SCS), etc.; and (3) phosphorous-bearing chemicals, such as sodium tripolyphosphate (STPP), sodium hexametaphosphate (SFMP), trisodium phosphate (TSP), Tetrasodiumpyrophosphate (TSPP), etc. With the improved collector, the separation selectivity and phosphate recovery may be significantly improved.

A method for recycling organic waste material containing phosphorus oxides and metal oxides is particularly suited for recycling sewage sludge. The waste materials are mixed with chlorine carriers and then heat-treated at an air ratio of 0.851.6 and at least partially oxidized. The metal chlorides thus formed are drawn off and recovered and the fraction remaining after the metal chlorides have been drawn off is subjected to reduction in order to obtain elemental phosphorus.

A method for recycling organic waste material containing phosphorus oxides and metal oxides is particularly suited for recycling sewage sludge. The waste materials are mixed with chlorine carriers and then heat-treated at an air ratio of 0.851.6 and at least partially oxidized. The metal chlorides thus formed are drawn off and recovered and the fraction remaining after the metal chlorides have been drawn off is subjected to reduction in order to obtain elemental phosphorus.

The invention relates to a method for preparing an aqueous suspension of at least one phosphate material, comprising, dispersing, in water, particles of phosphate material in the presence of at least one additive of the anionic polymer of acrylic acid or of methacrylic acid type. The suspension according to the invention has a viscosity of less than 1500 mPa.Math.s. The invention also relates to the conditioning of the phosphate material associated with the anionic polymer, for its subsequent treatment with at least one strong acid, for the industrial preparation of phosphoric acid.

The invention relates to a method for preparing an aqueous suspension of at least one phosphate material, comprising, dispersing, in water, particles of phosphate material in the presence of at least one additive of the anionic polymer of acrylic acid or of methacrylic acid type. The suspension according to the invention has a viscosity of less than 1500 mPa.Math.s. The invention also relates to the conditioning of the phosphate material associated with the anionic polymer, for its subsequent treatment with at least one strong acid, for the industrial preparation of phosphoric acid.