Abstract: The present invention relates to a method of producing and purifying a high-purity anhydrosugar alcohol in high yield by a simple process and apparatus, the method includes the steps of: allowing a sugar alcohol to react in the presence of an acid catalyst in a reactor, and, at the same time, evaporating a product of the reaction; cooling the evaporated product to remove water and obtain a crude anhydrosugar alcohol; and introducing the crude anhydrosugar alcohol into a melt crystallization process to obtain a high-purity anhydrosugar alcohol.

Abstract: The present invention relates to a method of producing anhydrosugar alcohol by dehydrating sugar alcohol at high pressure in the presence of a catalyst which is less acidic than a conventional sulfuric acid catalyst and which can suppress side reactions at high temperature. According to the present invention, anhydrosugar alcohol can be produced in a yield similar to that in a vacuum reaction.

Abstract: The present invention relates to a method for producing anhydrosugar alcohol, and more particularly to a method of producing anhydrosugar alcohol using a solvent including at least two components that form an azeotrope with water at atmospheric pressure and that have significantly different boiling points. The method for producing anhydrosugar alcohol according to the present invention can increase the yield of anhydrosugar alcohol by efficiently controlling the reaction temperature by use of a solvent including at least two components that form an azeotrope with water at atmospheric pressure and that have significantly different boiling points.

Abstract: A method for producing anhydrosugar alcohol according to the present invention can increase the yield of anhydrosugar alcohol even in the absence of a catalyst or in the presence of a small amount of a transition metal salt catalyst by controlling the temperature of a high-temperature reaction, which converts sugar alcohol to anhydrosugar alcohol, in two steps, that is, a first low-temperature reaction step and a second high-temperature reaction step.

Abstract: Provided is a method of producing carbon nanotubes by supplying a catalyst and a carbon source to a fluidized bed reactor. The fluidized bed reactor has an expanded zone. A flow velocity (linear velocity) of a raw material supplied to the fluidized bed reactor is equal to or higher than a terminal velocity of an internal material in the fluidized bed reactor.

Abstract: A method of producing carbon nanotubes in a fluidized bed reactor includes preparing a carbon nanotube by supplying a catalyst and a carbon source to an interior of the fluidized bed reactor having an internal pressure of 0.5 barg to 1.2 barg (gauge pressure), thereby improving the yield and purity of carbon nanotubes.

Abstract: The present invention provides a method for producing anhydrosugar alcohol, including: feeding sugar alcohol into a reactor and performing a dehydration reaction of the fed sugar alcohol to produce anhydrosugar alcohol; and supplying steam to the reactor to evaporate the produced anhydrosugar alcohol. According to the present invention, anhydrosugar alcohol can be produced in a high yield by increasing the specific surface area of reaction mother liquor and reducing the partial pressure of the product.

Abstract: The present invention relates to a method for producing anhydrosugar alcohol using an organic additive having one hydroxyl group. The present invention makes it possible to prevent oligomers and polymers from being produced by polymerization of isosorbide during dehydration of sorbitol molecules, and thus solves problems, including a reduction in fluidity in a dehydration reactor, interference with the flow of fluids in the reactor and pipelines, and interference with stirrer operation, which occur due to the oligomers and polymers.

Abstract: Disclosed is a method for producing a carbon nanotube, including supplying a carbon nanotube and a catalyst to a reactor in a predetermined order or simultaneously and fluidizing them to form a fluidized bed, wherein a difference in minimum fluidization velocities (?V) according to Formula 1 below is 5 cm/s or less: [Formula 1] Difference in minimum fluidization velocities (?V, cm/s)=|Vcat?Vcntproduct| wherein Vcat is a minimum fluidization velocity of catalyst, and VCNTproduct is a minimum fluidization velocity of carbon nanotubes supplied to a reactor in the step of forming a fluidized bed.

Abstract: The present invention relates to a method of producing and purifying a high-purity anhydrosugar alcohol in high yield by a simple process and apparatus, the method includes the steps of: allowing a sugar alcohol to react in the presence of an acid catalyst in a reactor, and, at the same time, evaporating a product of the reaction; cooling the evaporated product to remove water and obtain a crude anhydrosugar alcohol; and introducing the crude anhydrosugar alcohol into a melt crystallization process to obtain a high-purity anhydrosugar alcohol.

Abstract: The present invention relates to a method for producing anhydrosugar alcohol, and more particularly to a method of producing anhydrosugar alcohol using a solvent including at least two components that form an azeotrope with water at atmospheric pressure and that have significantly different boiling points. The method for producing anhydrosugar alcohol according to the present invention can increase the yield of anhydrosugar alcohol by efficiently controlling the reaction temperature by use of a solvent including at least two components that form an azeotrope with water at atmospheric pressure and that have significantly different boiling points.

Abstract: A method for producing anhydrosugar alcohol according to the present invention can increase the yield of anhydrosugar alcohol even in the absence of a catalyst or in the presence of a small amount of a transition metal salt catalyst by controlling the temperature of a high-temperature reaction, which converts sugar alcohol to anhydrosugar alcohol, in two steps, that is, a first low-temperature reaction step and a second high-temperature reaction step.

Abstract: The present invention relates to a method of producing anhydrosugar alcohol by dehydrating sugar alcohol at high pressure in the presence of a catalyst which is less acidic than a conventional sulfuric acid catalyst and which can suppress side reactions at high temperature. According to the present invention, anhydrosugar alcohol can be produced in a yield similar to that in a vacuum reaction.

Abstract: The present invention relates to a method for producing anhydrosugar alcohol using an organic additive having one hydroxyl group. The present invention makes it possible to prevent oligomers and polymers from being produced by polymerization of isosorbide during dehydration of sorbitol molecules, and thus solves problems, including a reduction in fluidity in a dehydration reactor, interference with the flow of fluids in the reactor and pipelines, and interference with stirrer operation, which occur due to the oligomers and polymers.

Abstract: The present invention provides a method for preparing anhydrosugar alcohol, in which the reaction temperature in a vacuum reaction that converts sugar alcohol into anhydrosugar alcohol is controlled to two steps of temperature that is, a first-step low reaction temperature of 100 to 150° C. and a second-step high reaction temperature of 151 to 240° C., so that the selectivity for the intermediate product 1,4-sorbitan can be increased, thereby increasing the yield of anhydrosugar alcohol.

Abstract: The present invention provides a method for producing anhydrosugar alcohol, including: feeding sugar alcohol into a reactor and performing a dehydration reaction of the fed sugar alcohol to produce anhydrosugar alcohol; and supplying steam to the reactor to evaporate the produced anhydrosugar alcohol. According to the present invention, anhydrosugar alcohol can be produced in a high yield by increasing the specific surface area of reaction mother liquor and reducing the partial pressure of the product.