Abstract: A method is provided for the wet surface treatment of titanium dioxide, in order to produce durable universal grade titanium dioxide rutile pigment with superior optical properties. The method is characterized in that, a hydrous zirconia and silica composite layer is co-precipitated at acidic pH. Then, a layer of alumina is precipitated under a range of pH required for complete precipitation above the initial composite layer. The upper pH limit of the slurry during the alumina precipitation can be well controlled to avoid any chance for dissolution or damage of the composite zirconia-silica layer formed. Zirconia-silica composite layers and alumina thus precipitated advantageously improve the competence of the layers formed over a TiO2 base and provide improved durability with superior optical performance. The total surface treatment cycle time and chemicals used are minimal compared to conventional methods. Improvements in throughput and washing efficiency are also realized.

Abstract: A method for the purification of spent sulfuric acid and particularly the purification of spent acid, from titanium dioxide rutile manufacture through a chloride route, is provided. In the chloride route of titanium dioxide manufacture, sulfuric acid is used to clean the un-reacted gaseous flow coming out of the oxidizer, so the spent acid mainly contains un-reacted Ti4+ ions, trace amounts of Fe3+ ions, and NO2 gas. Titanium phosphate can be precipitated using acidic and or alkaline phosphate-containing precipitants in stoichiometric amounts. The method can include the addition of cutting water to commence the precipitation in two or more steps, when an acidic precipitant is used, and in one step with half the volume of water when an alkaline precipitant is used.

Abstract: A photocatalyst is provided that comprises activated carbon produced from date pits, impregnated with TiO2. The activated carbon can have a porous surface that can attract and trap pollutants flowing in air or water. The photocatalyst can be made by a method that includes preparing activated carbon by calcining date pits to form a precursor material, and then impregnating the precursor material with titanium dioxide.

Abstract: A method of preparing coated titanium dioxide particles is provided. The method can include forming an aqueous suspension of titanium dioxide particles having a pH of from about 5.0 to about 7.0; adding a zirconium oxide-forming solution to the suspension in an amount sufficient to decrease the pH of the suspension to about 4.0 or lower; forming a zirconium oxide coating on the titanium dioxide particles to form a suspension of coated particles; adding an aluminum oxide-forming solution to the suspension of coated particles in an amount sufficient to increase the pH of the suspension to about 9.0 or higher; and forming an aluminum oxide coating on the coated particles to form a product.

Abstract: A method is provided for adsorbing organic molecules, pollutants, or both, by contacting the organic molecules, pollutants, or both, with a photocatalyst. The photocatalyst can be made by a method that includes preparing activated carbon by calcining date pits to form a precursor material, and then impregnating the precursor material with titanium dioxide.

Abstract: A method is provided for the wet surface treatment of titanium dioxide, in order to produce durable universal grade titanium dioxide rutile pigment with superior optical properties. The method is characterized in that, a hydrous zirconia and silica composite layer is co-precipitated at acidic pH. Then, a layer of alumina is precipitated under a range of pH required for complete precipitation above the initial composite layer. The upper pH limit of the slurry during the alumina precipitation can be well controlled to avoid any chance for dissolution or damage of the composite zirconia-silica layer formed. Zirconia-silica composite layers and alumina thus precipitated advantageously improve the competence of the layers formed over a TiO2 base and provide improved durability with superior optical performance. The total surface treatment cycle time and chemicals used are minimal compared to conventional methods. Improvements in throughput and washing efficiency are also realized.

Abstract: Sodium silicate solutions of modulus 3.0 to 3.8 are provided. In some embodiments, the solution is made by a process that uses two specific principal reaction stages. A sodium silicate solution having a low SiO2:Na2O molar ratio, in the range from 2.0 to 2.8, is first produced by reaction of the SSS, as a cost-effective SiO2 source, with aqueous caustic soda. The conversion of this intermediate sodium silicate solution of low modulus to a high SiO2:Na2O molar ratio is made possible by using a SiO2 source that is prepared as precipitated amorphous silica from the intermediate sodium silicate solution produced above.

Abstract: A method for the purification of spent sulfuric acid and particularly the purification of spent acid, from titanium dioxide rutile manufacture through a chloride route, is provided. In the chloride route of titanium dioxide manufacture, sulfuric acid is used to clean the un-reacted gaseous flow coming out of the oxidizer, so the spent acid mainly contains un-reacted Ti4+ ions, trace amounts of Fe3+ ions, and NO2 gas. Titanium phosphate can be precipitated using acidic and or alkaline phosphate-containing precipitants in stoichiometric amounts. The method can include the addition of cutting water to commence the precipitation in two or more steps, when an acidic precipitant is used, and in one step with half the volume of water when an alkaline precipitant is used.

Abstract: A method is provided for treating silica sand scrubs (SSS) generated and accumulated as waste in the chloride manufacturing process of titanium dioxide pigment. A hydrothermal process is used to produce sodium silicate solutions of modulus 3.0 to 3.8, and precipitated silicas. In some embodiments, the process uses two specific principal reaction stages. A sodium silicate solution having a low SiO2:Na2O molar ratio, in the range from 2.0 to 2.8, is first produced by reaction of the SSS, as a cost-effective SiO2 source, with aqueous caustic soda. The conversion of this intermediate sodium silicate solution of low modulus to a high SiO2:Na2O molar ratio is made possible by using a SiO2 source that is prepared as precipitated amorphous silica from the intermediate sodium silicate solution produced above.

Abstract: TiO2 nanoparticles and methods of producing the same are provided. The nanoparticles can be processed by neutralization, calcination, and/or micronization. The TiO2 nanoparticle size is controlled by controlling synthetic and process conditions. TiO2 nanoparticles produced are of the anatase polymorph, of the rutile polymorph, or a mixture thereof, and have particle sizes in the range of from 10 nm to 100 nm.

Abstract: A method is provided for adsorbing organic molecules, pollutants, or both, by contacting the organic molecules, pollutants, or both, with a photocatalyst. The photocatalyst can be made by a method that includes preparing activated carbon by calcining date pits to form a precursor material, and then impregnating the precursor material with titanium dioxide.

Abstract: TiO2 nanoparticles and methods of producing the same are provided. The nanoparticles can be processed by neutralization, calcination, and/or micronization. The TiO2 nanoparticle size is controlled by controlling synthetic and process conditions. TiO2 nanoparticles produced are of the anatase polymorph, of the rutile polymorph, or a mixture thereof, and have particle sizes in the range of from 10 nm to 100 nm.

Abstract: A method is provided for treating silica sand scrubs (SSS) generated and accumulated as waste in the chloride manufacturing process of titanium dioxide pigment. A hydrothermal process is used to produce sodium silicate solutions of modulus 3.0 to 3.8, and precipitated silicas. In some embodiments, the process uses two specific principal reaction stages. A sodium silicate solution having a low SiO2:Na2O molar ratio, in the range from 2.0 to 2.8, is first produced by reaction of the SSS, as a cost-effective SiO2 source, with aqueous caustic soda. The conversion of this intermediate sodium silicate solution of low modulus to a high SiO2:Na2O molar ratio is made possible by using a SiO2 source that is prepared as precipitated amorphous silica from the intermediate sodium silicate solution produced above.

Abstract: A method is provided for producing TiO2 nanoparticles. The nanoparticles can be further processed by neutralization, calcination, and/or micronization. The TiO2 nanoparticle size is controlled by controlling synthetic and process conditions. TiO2 nanoparticles produced are of the anatase polymorph, of the rutile polymorph, or a mixture thereof, and have particle sizes in the range of from 10 nm to 100 nm.

Abstract: A photocatalyst is provided that comprises activated carbon produced from date pits, impregnated with TiO2. The activated carbon can have a porous surface that can attract and trap pollutants flowing in air or water. The photocatalyst can be made by a method that includes preparing activated carbon by calcining date pits to form a precursor material, and then impregnating the precursor material with titanium dioxide.

Abstract: A photocatalyst is provided that comprises activated carbon produced from date pits, impregnated with TiO2. The activated carbon can have a porous surface that can attract and trap pollutants flowing in air or water. The photocatalyst can be made by a method that includes preparing activated carbon by calcining date pits to form a precursor material, and then impregnating the precursor material with titanium dioxide.

Abstract: A photocatalyst is provided that comprises activated carbon produced from date pits, impregnated with TiO2. The activated carbon can have a porous surface that can attract and trap pollutants flowing in air or water. The photocatalyst can be made by a method that includes preparing activated carbon by calcining date pits to form a precursor material, and then impregnating the precursor material with titanium dioxide.

Abstract: An reinforced cementitious material structure is provided that includes a cementitious material made from an industrial waste byproduct from a titanium metal production process or from a titanium dioxide production process. The byproduct is used as a partial cement replacement. In some embodiments, the reinforced cementitious material structure can comprise a metal reinforcing structure in contact with a hardened cementitious material. The hardened cementitious material can comprise cement and the industrial waste byproduct. The cement can be used to make concrete and other cementitious material products for structural and non-structural uses, with little or no corrosion or other deterioration of an embedded metal reinforcing structure.

Abstract: A method is provided for treating silica sand scrubs (SSS) generated and accumulated as waste in the chloride manufacturing process of titanium dioxide pigment. A hydrothermal process is used to produce sodium silicate solutions of modulus 3.0 to 3.8, and precipitated silicas. In some embodiments, the process uses two specific principal reaction stages. A sodium silicate solution having a low SiO2:Na2O molar ratio, in the range from 2.0 to 2.8, is first produced by reaction of the SSS, as a cost-effective SiO2 source, with aqueous caustic soda. The conversion of this intermediate sodium silicate solution of low modulus to a high SiO2:Na2O molar ratio is made possible by using a SiO2 source that is prepared as precipitated amorphous silica from the intermediate sodium silicate solution produced above.

Abstract: A method is provided for treating silica sand scrubs (SSS) generated and accumulated as waste in the chloride manufacturing process of titanium dioxide pigment. A hydrothermal process is used to produce sodium silicate solutions of modulus 3.0 to 3.8, and precipitated silicas. In some embodiments, the process uses two specific principal reaction stages. A sodium silicate solution having a low SiO2:Na2O molar ratio, in the range from 2.0 to 2.8, is first produced by reaction of the SSS, as a cost-effective SiO2 source, with aqueous caustic soda. The conversion of this intermediate sodium silicate solution of low modulus to a high SiO2:Na2O molar ratio is made possible by using a SiO2 source that is prepared as precipitated amorphous silica from the intermediate sodium silicate solution produced above.