Hodogaya Chemical Co., Ltd.

Japan Energy Corporation

Bussan Nanotech Research Institute, Inc.

Takayuki Tsukada

Jiayi Shan

Tsuyoshi Okubo

Masayuki Mori

Fuminori Munekane

Koichi Handa

Subiantoro

Kazuhiro Osato

Hiroki Koyama

Hideo Segawa

Naoharu Igarashi

Hideaki Kumagai

Kenji Nakamura

Motoi Saito

Yuji Ohashi

Hiroyuki Nakamura

Disclosed is a fine carbon fibrous structure which comprises carbon fibers and granular parts, wherein at least two granular parts connect by at least one of the carbon fibers; wherein the fine carbon fibrous structure have a D/Dratio of 1.3 to 10, wherein the Dis the median diameter of outer diameters of the carbon fibers and the Dis the area-based circle-equivalent median diameter of the particles; wherein the granular parts have a Dof 0.05 to 0.4 &#x3bc;m; wherein the carbon fibers have a median length of not more than 20 &#x3bc;m; wherein the granular parts are produced in a growth process of the carbon fibers; and wherein at least a graphene layer which exists on and constitutes the surface of each granular part is continued on a graphene layer which exists on and constitutes the surface of the carbon fiber which connects between the granular parts.

Fine carbon fibrous structure

A method for forming a carbon fibrous structure having a plurality of granular parts, to which a plurality of carbon fibers are bound, includes heating a mixture of a carbon source and a catalyst at a temperature between 800 &#xb0; C. and 1300 &#xb0; C. to produce aggregates of a first intermediate, heating the aggregates of the first intermediate to remove hydrocarbons, at a temperature between 800 &#xb0; C. and 1200 &#xb0; C. to produce aggregates of a first product, heating the aggregates of the first product at a temperature between 2400 &#xb0; C. and 3000 &#xb0; C. to produce aggregates of a final product; and pulverizing the aggregates of the final product such that area-based circle-equivalent mean diameter of each aggregate of the carbon fibrous structure of the product is 50-100 &#x3bc;m, bulk density of the carbon fibrous structure is 0.0001-0.02 g/cm, and powder resistance under pressed density of 0.8g/cmis not more than 0.02 &#x3a9;&#xb7;cm.

Carbon fibrous structure

An composite material is disclosed, which includes carbon fibrous structures which are capable of being included in a relatively large amount in the composite material, and which are capable of improving the physical properties, such as electric, mechanical, or thermal properties. The carbon fibrous structure comprises (a) carbon fibrous structures each of which comprises a three dimensional network of carbon fibers, each of the carbon fibers having an outside diameter of 15-100 nm, wherein the carbon fibrous structure further comprises a granular part, at which the carbon fibers are bound in a state that the carbon fibers are extended outwardly therefrom, and wherein the granular part is produced in a growth process of the carbon fibers, and (b) an material other than the carbon fibrous structures, wherein the amount of carbon fibrous structures added is more than 30% and not more than 100% by weight of the total weight of the composite.

Composite material

Disclosed is a carbon fibrous structure which comprises a granular part and 2-20 pieces of carbon fibers each of which has an outside diameter of 15-100 nm and which are extend outwardly from the granular part, wherein the granular part is produced in a growth process of the carbon fibers, wherein the size of granular part is 1.3 or more of times larger than the outside diameter of the carbon fibers, and wherein the mean length of the carbon fibers is not more than 20 &#x3bc;m. The carbon fibrous structure improves the physical properties of the matrix, such as electric, mechanical, or thermal properties, while maintaining the other properties of the matrix, even when added at a small amount.

A method for producing a hydrorefining catalyst of the present invention has a step of preparing an aluminum solution containing phosphorus in a molar ratio of 0.001 to 0.05 with respect to aluminum; a step of neutralizing the prepared aluminum solution to produce a pseudo-boehmite powder; a step of forming the pseudo-boehmite powder followed by performing calcination at a temperature of not less than 650&#xb0; C. to obtain a carrier; and a step of carrying a hydrogenation-active metal on the pseudo-boehmite powder or the carrier. The dispersion of the concentration distribution of phosphorus in the carrier of the obtained catalyst is within 10%. This method makes it possible to obtain the hydrorefining catalyst which has a practically sufficient mechanical strength and which has an excellent activity.

Hydro-refining catalyst, carrier for use therein and method for production thereof

A composite material includes a matrix and carbon fibrous structures. The carbon fibrous structure has a three dimensional network of carbon fibers, each having an outside diameter of 15&#x2013;100 nm, and has a granular part with which carbon fibers are bound in a state such that the carbon fibers extend outwardly from the granular part, and the granular part being produced in a growth process of the carbon fibers. The additive amount of the carbon fibers is in the range of 0.1 to 30% by weight of total weight of the composite material.

A heavy oil hydrorefining catalyst of the present invention is such that the total volume of pores with a diameter of 60 nm or less is at least 0.5 mL/g, and the pore diameter distribution has a broad band over a pore diameter range of 8 to 30 nm. The hydrorefining catalyst has excellent desulfurization characteristics and excellent demetalization characteristics, and its performance can be maintained over an extended period. When this catalyst is used in a hydrorefining apparatus equipped with a plurality of catalyst layers, the apparatus can be operated stably at a higher temperature than in the past without decreasing the desulfurization performance, and this also enhances the demetalization characteristics.

Hydrofining catalyst and hydrofining process

Pseudo-boehmite, which is a raw material for a catalyst carrier for hydrogenation refining, is produced by mixing, under a predetermined condition, an aluminate aqueous solution produced from an alkaline etching step for aluminum in an alumite treatment and an acidic aluminum aqueous solution produced from an anodization step for aluminum in the alumite treatment. Pseudo-boehmite can be also produced by maturing, with an alkaline solution, an aluminum hydroxide sludge produced from a washing step for aluminum in the alumite treatment. It is possible to establish a method for producing pseudo-boehmite, which makes it possible to reutilize a resource at extremely low cost by utilizing a treatment waste liquid and a sludge in an alumite treatment site.

Method of manufacturing pseudo-boehmite

An aluminum salt solution and an alkali aluminate solution are subjected to a neutralization reaction to precipitate and form a pseudo-boehmite powder. The neutralization reaction is performed under a condition in which the reaction temperature is within a range of 55 to 71&deg; C., pH is within a range of 8.5 to 9.5, and the solution feed time is within a range of 7 to 25 minutes. The obtained pseudo-boehmite is as follows. That is, the pore volume concerning pores having a pore diameter ranging from 20 to 600 &angst; is within a range of 0.8 to 1.8 cc/g as measured by the nitrogen adsorption method, and the maximum value of variation ratio dV/dD of the pore volume with respect to the pore diameter as measured by the BJH method is not more than 0.018 cc/g&bull;&angst;. When the pseudo-boehmite is used, it is possible to produce a catalyst carrier for hydrogenation refining, which has a sharp pore diameter distribution and which suffers less decrease in strength upon impregnation with a catalyst solution.

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Tokyo, Japan

Takayuki Tsukada