C01G37/033

Preparation method of particle size-controlled, chromium oxide particles or composite particles of iron oxide-chromium alloy and chromium oxide

Provided are particle size-controlled, chromium oxide particles or composite particles of iron oxide-chromium alloy and chromium oxide; a preparation method thereof; and use thereof, in which the chromium oxide particles or the composite particles of iron oxide-chromium alloy and chromium oxide having a desired particle size are prepared in a simpler and more efficient manner by using porous carbon material particles having a large pore volume as a sacrificial template. When the chromium oxide particles or the composite particles of iron oxide-chromium alloy and chromium oxide thus obtained are applied to gas-phase and liquid-phase catalytic reactions, they are advantageous in terms of diffusion of reactants due to particle uniformity, high-temperature stability may be obtained, and excellent reaction results may be obtained under severe reaction environment.

Preparation method of particle size-controlled, chromium oxide particles or composite particles of iron oxide-chromium alloy and chromium oxide

Provided are particle size-controlled, chromium oxide particles or composite particles of iron oxide-chromium alloy and chromium oxide; a preparation method thereof; and use thereof, in which the chromium oxide particles or the composite particles of iron oxide-chromium alloy and chromium oxide having a desired particle size are prepared in a simpler and more efficient manner by using porous carbon material particles having a large pore volume as a sacrificial template. When the chromium oxide particles or the composite particles of iron oxide-chromium alloy and chromium oxide thus obtained are applied to gas-phase and liquid-phase catalytic reactions, they are advantageous in terms of diffusion of reactants due to particle uniformity, high-temperature stability may be obtained, and excellent reaction results may be obtained under severe reaction environment.

Mesoporous materials and processes for preparation thereof

A process for preparing a mesoporous material, e.g., transition metal oxide, sulfide, selenide or telluride, Lanthanide metal oxide, sulfide, selenide or telluride, a post-transition metal oxide, sulfide, selenide or telluride, and metalloid oxide, sulfide, selenide or telluride. The process comprises providing a micellar solution comprising a metal precursor, an interface modifier, a hydrotropic or lyotropic ion precursor, and a surfactant; and heating the micellar solution at a temperature and for a period of time sufficient to form the mesoporous material. A mesoporous material prepared by the above process. A method of controlling nano-sized wall crystallinity and mesoporosity in mesoporous materials. The method comprises providing a micellar solution comprising a metal precursor, an interface modifier, a hydrotropic or lyotropic ion precursor, and a surfactant; and heating the micellar solution at a temperature and for a period of time sufficient to control nano-sized wall crystallinity and mesoporosity in the mesoporous materials. Mesoporous materials and a method of tuning structural properties of mesoporous materials.

Mesoporous materials and processes for preparation thereof

A process for preparing a mesoporous material, e.g., transition metal oxide, sulfide, selenide or telluride, Lanthanide metal oxide, sulfide, selenide or telluride, a post-transition metal oxide, sulfide, selenide or telluride, and metalloid oxide, sulfide, selenide or telluride. The process comprises providing a micellar solution comprising a metal precursor, an interface modifier, a hydrotropic or lyotropic ion precursor, and a surfactant; and heating the micellar solution at a temperature and for a period of time sufficient to form the mesoporous material. A mesoporous material prepared by the above process. A method of controlling nano-sized wall crystallinity and mesoporosity in mesoporous materials. The method comprises providing a micellar solution comprising a metal precursor, an interface modifier, a hydrotropic or lyotropic ion precursor, and a surfactant; and heating the micellar solution at a temperature and for a period of time sufficient to control nano-sized wall crystallinity and mesoporosity in the mesoporous materials. Mesoporous materials and a method of tuning structural properties of mesoporous materials.

Process for preparing chromium(III) oxide

The present invention relates to a process for preparing chromium(III) oxide by reaction of alkali metal chromate with gaseous ammonia, subsequent hydrolysis, isolation of the hydrolysis product and calcination.

Process for preparing chromium(III) oxide

The present invention relates to a process for preparing chromium(III) oxide by reaction of alkali metal chromate with gaseous ammonia, subsequent hydrolysis, isolation of the hydrolysis product and calcination.

PREPARATION METHOD OF PARTICLE SIZE-CONTROLLED, CHROMIUM OXIDE PARTICLES OR COMPOSITE PARTICLES OF IRON OXIDE-CHROMIUM ALLOY AND CHROMIUM OXIDE

Provided are particle size-controlled, chromium oxide particles or composite particles of iron oxide-chromium alloy and chromium oxide; a preparation method thereof; and use thereof, in which the chromium oxide particles or the composite particles of iron oxide-chromium alloy and chromium oxide having a desired particle size are prepared in a simpler and more efficient manner by using porous carbon material particles having a large pore volume as a sacrificial template. When the chromium oxide particles or the composite particles of iron oxide-chromium alloy and chromium oxide thus obtained are applied to gas-phase and liquid-phase catalytic reactions, they are advantageous in terms of diffusion of reactants due to particle uniformity, high-temperature stability may be obtained, and excellent reaction results may be obtained under severe reaction environment.

PREPARATION METHOD OF PARTICLE SIZE-CONTROLLED, CHROMIUM OXIDE PARTICLES OR COMPOSITE PARTICLES OF IRON OXIDE-CHROMIUM ALLOY AND CHROMIUM OXIDE

Provided are particle size-controlled, chromium oxide particles or composite particles of iron oxide-chromium alloy and chromium oxide; a preparation method thereof; and use thereof, in which the chromium oxide particles or the composite particles of iron oxide-chromium alloy and chromium oxide having a desired particle size are prepared in a simpler and more efficient manner by using porous carbon material particles having a large pore volume as a sacrificial template. When the chromium oxide particles or the composite particles of iron oxide-chromium alloy and chromium oxide thus obtained are applied to gas-phase and liquid-phase catalytic reactions, they are advantageous in terms of diffusion of reactants due to particle uniformity, high-temperature stability may be obtained, and excellent reaction results may be obtained under severe reaction environment.

Process for preparing chromium(III) oxide

Process for preparing chromium(III) oxide, which comprises the steps: a) reaction of sodium monochromate with gaseous ammonia, in particular at a temperature of from 200 to 800 C., b) hydrolysis of the reaction product obtained in step a) with the pH of the water for the hydrolysis being reduced before the hydrolysis or that of the alkaline mother liquor being reduced during or after the hydrolysis, to a value of from 4 to 11, preferably from 5 to 10, by means of an acid, c) isolation of the hydrolysis product which has precipitated in step b), preferably at a pH of from 4 to 11, in particular from 5 to 10, and optionally washing and optionally drying and d) calcination of the hydrolysis product obtained in step c) at a temperature of from 700 to 1400 C., in particular from 800 to 1300 C.

Process for preparing chromium(III) oxide

Process for preparing chromium(III) oxide, which comprises the steps: a) reaction of sodium monochromate with gaseous ammonia, in particular at a temperature of from 200 to 800 C., b) hydrolysis of the reaction product obtained in step a) with the pH of the water for the hydrolysis being reduced before the hydrolysis or that of the alkaline mother liquor being reduced during or after the hydrolysis, to a value of from 4 to 11, preferably from 5 to 10, by means of an acid, c) isolation of the hydrolysis product which has precipitated in step b), preferably at a pH of from 4 to 11, in particular from 5 to 10, and optionally washing and optionally drying and d) calcination of the hydrolysis product obtained in step c) at a temperature of from 700 to 1400 C., in particular from 800 to 1300 C.