DE2153308A1 - Process for the production of carbonaceous porous objects - Google Patents

Description

October 30, 1970, Japan, No. 952II / I970

Applicant: KTJREHA KAGAKU KOGYO KABUSHIKI KAISHA No. 8, Horidome-cho I-chome Nihonbashl, Chuo-ku Tokyo / JAPAN

Process for producing carbonaceous porous objects

The invention relates to a method for producing a carbonaceous porous material and in particular a method for producing a carbonaceous material, in the case of hollow carbon microspheres with a Binders are bonded together to form a shaped fresh foam, which is then carbonized will.

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The invention is thus directed towards providing a new economic method to carbonaceous porous material of low density and having excellent properties [

to produce a variety of industrial applications has application opportunities.

It has been found that the object of the invention can be achieved in an advantageous manner in that hollow microspheres are spherical shells of carbon connected with a binder to form a molded fresh foam, which is then _carbonized: is. . .

The process for producing hollow microsphere shells from ■ Carbon as used in the present invention is detailed in Japanese Patent Application No. 45625 / 1970 or the German patent application P2I26262.4, which is based on the Name filed by the same applicant. ■

According to the disclosure in this aforementioned earlier application, the method for producing hollow microsphere shells consists in that bituminous coal or petroleum pitch with an atomic ratio of hydrogen to carbon of 0.2 to 1.0 and a softening point of 100 to 350 ° C. uniformly with an organic solvent , in which the pitch is soluble, is mixed, then this mixture is dispersed in water which contains a suspending agent, the solvent from the pitch thus obtained! solvent mixture is removed, whereby the content of solvent is reduced to 0.2 to IO % , the material is shaped by short-term heating, the resulting microsphere shells made of pitch are made infusible in an oxidizing gas or a liquid and the material treated in this way in an inert Atmosphere is carbonized .

The feature of the present invention resides in the production of carbonaceous porous material composed of carbon microsphere shells using the aforesaid hollow carbon microsphere shells as a raw material.

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The features and objects of the present invention result from the following description.

According to the inventive method, the hollow carbon 'fabric microsphere shells with a binder, such as e thermosetting resin) or thermosetting inorganic material; to form a molded fresh foam, then the molded fresh foam is heated to harden and finally in a non-oxidizing gas! atmosphere carbonized to obtain the desired carbonaceous porous article.

The preferred hollow carbon microsphere shells of the present invention have an average particle diameter of I μ to IOOO μ, a debris weight of 0.01 to 0.8 g / cm and an average wall thickness of 0.1 to 100 μ.

The ones used to join such hollow carbon microsphere shells The binders used for the production of the fresh foam can be made from the aforementioned thermosetting resins, thermosetting resins inorganic materials or carbonizable organic materials exist. They are, for example, thermosetting Resins such as phenolic resins, furfuryl alcohol resin, furfuryl aldehyde resin, epoxy resin, silicone resin, alkyd resins or unsaturated polyester resins} thermosetting organic materials such as water glass, colloidal silica, clay, etc; carbonaceous organic materials such as cellulose, starch, caramel, polyvinyl alcohol, polyacrylnytr11, polyvinylidene chloride, etc.

Although the amount of these binders used in the present Invention used, from the type of binder, the For-1 men of the hollow carbonaceous microsphere shells or the density of the carbonaceous porous objects to be molded depends, the amount of binder should be less or equivalent to the volume of the hollow carbon microsphere shells , preferably it should be in the range of 4 to 40 volume percent of the carbon microsphere shells. The solution

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Agent can also be used to dissolve or dilute the binder and thus facilitate the shaping of said carbon microsphere shells.

In the production process according to the invention, the binder, a hardener for it and a solvent for the binder are ^{intimately mixed in a mixer, for example a kneader, a Henschel mixer or a 11} V "mill, then this mixture is poured into the metal mold so that they einr ^'; is molded> pressure of 0.1 to IO kg / cm and then the dense mass is cured in the mold by being one minute to 24 hours at a temperature of room temperature is kept to 200 ° C to effect curing. hardeners such as aromatic amines, aliphatic amines, organic acid anhydrides, polyamide resins, organic peroxides, paratoluene sulfonic acid or phosphoric acid can be used according to the types of binders used the heating rate, that is, the rate of temperature rise If it is too slow, the process is poorly economical, while on the other hand, if the heating rate is too fast, the molded foam tends to crack, resulting in destruction or damage to the products Range from 0.5 to 10 ° C / min. within the temperature range from 300 to 1000 ° C. After this heating range has been passed through, the temperature can, if necessary, be increased quickly from 1000 to 2000 ° C in order to complete the carbonization.

The carbonaceous porous material obtained in this way has the following properties

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2151308

Rubble weight: Compressive strength: Operating temperature:

Permeability: water permeability i

0.05 to 1.00 g / cm 5 to 500 kg / cm ²

up to 3,000 ° C (in a non-oxidizing atmosphere)

3 2 0.2 to IO cm / cm cm H _n O sec.

2 to 200x10 '

3 2 cm cm / cm cm H ₂ O sec

The carbonaceous porous article thus obtained according to the present invention has an extremely low thermal conductivity, a higher mechanical strength and a density in the range of 0.05 to 1.00 g / cm. The advantages and excellent properties stem from the fact that the carbon-containing porous article of hollow carbon microspheres shells which serve as structural elements, and further that a predominant portion ^and the porosity within the poxiösen Gegenstandei | facilitated excessively distributed, closed pores or cells assembled is .

As can be seen from the foregoing, the carbonaceous porous material according to the present invention provides various dene excellent properties, making it suitable for use as a high temperature insulation material, as an insulation material for Refrigerators and as a material for soundproof walls, chemical reactors, reaction columns, open steam pipes, various Kinds of filters, as a gas inlet plate, as an absorption plate, as a diaphragm, etc. is suitable. The present invention thus creates a new material which for a is suitable for a wide range of applications.

The following examples serve to further explain the method of the invention.

Example I. 10 g of a 30% ethanol solution of a resol-like phenolic resin

("Priohen" No. 5,900 manufactured by Dainippon Ink. Co.]

ΉίκΓΰ and 50 ml hollow carbon / spherical shells with a bulk weight of 0.15 g / cm, an average particle diameter of Ι40μ,

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ι a mean wall thickness of I2u and a water pressure resistance

2!

of over 30 kg / cm were determined using a small Henschel ^ Mixer mixed, then the mixture thus obtained is placed in a stainless steel mold of 45 mm in diameter under pressure

2 ^:

of 0.5 kg / cm to produce a fresh compact. The molded compact was then placed on a Tem-j for two hours to cure temperature of 200 ° C and then the cured j foam was heated at a heating rate of 1 ° C / min. in a! Nitrogen atmosphere heated to 1000 ° C for carbonization. the Properties of this porous article are listed in Table I. ;

| l Example 2 I 50 ml of the hollow carbon microcups used in Example I! Gel bowls, 10 g of furfuryl alcohol and 0.5 g of a hardener made from paratoluene sulfonic acid were mixed in a Henschel mixer and the mixture thus obtained was treated in the same manner as described in Example I so that a carbonaceous porous article was obtained. The properties of this material are listed in Table I. ;

Example 3 I.

50 ml of the hollow carbon micro-ball shells and IO g of one 10% strength potato starch solution were in a small Henschel; Mixer mixed and the mixture thus obtained was poured into a mold; made of stainless steel and placed under a pressure of 0.2 kg /,

2 ■ '

cm formed into a fresh compact. The formed foam j

was then heated at 200 ° C for 12 hours to completely remove the water therefrom and to obtain a dry, molded fresh foam. This fresh foam was then, as described in Example I, for carbonization at a heating rate of 1 ° C./min. heated to 1,000 ° C. The properties of the carbon-containing porous article obtained in this way are listed in Table I below:

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Tabel I. Example I Example 2 Example 3 Bulk density g / cm ³ 0.13 0.21 0.15 Compressive strength kg / cm ² 21 38 II

Thermal conductivity _{nno n τ} «η τη Kcal / ra ηΛ ^{0> 09} ° ^'13 °' ^ID

From Table I above it can be seen that such carbonaceous porous body or material is very lightweight, high thermal insulation ability and a has high compressive strength.

Example 4

70 parts by weight from each of the groups listed below .. of hollow carbon microsphere shells with the three mean particle diameters: (a) 300 μ j

(b) 180 µ

(c) 100 µ

were each mixed with 30 parts by weight of a novolak-type phenolic resin in a ¹¹ V "-type mixer. The mixture thus obtained was" compression-molded at a temperature of 150 ° to a sheet 2.5 cm thick, which was then pressed for six hours under a nitrogen atmosphere was heated from 200 ° C to 100 ° C for carbonization and to produce a carbon-containing porous object. The properties of each carbon-containing article are listed in Table 2. ;

Table 2

Bulk weight g // cm ³ compressive strength kg / cm shear strength kg // cm

Thermal conductivity Kcal / m 0.08

3 hf "V gas permeability cm / cm /

ο
cm / cm HqO sec.

3 water permeability cm / cm / cm / cm H ₂ O sec.

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(a) (b) (c) 0.23 0.26 0.31 29.4 42.6 46.7 21.9 30.4 32.9 0.08 0.09 O.II 1.1 0.8 0.4 4.4 x 10 ^-3 4.3XIO " ³ 4.4XI0 ' ³

Claims (1)

Claims A method for producing carbon-containing porous objects, characterized in that carbon microsphere shells with a hollow structure with a Binder, the amount of which is based on the volume, is equivalent to or below the amount of the micro-spherical shells, are connected to one another, a shaped compact is produced therefrom, which is heated to harden and then in a carbonized non-oxidizing atmosphere. j 2. The method according to claim I, characterized gekennzze lehne t that the carbon micro-spherical shells with W of a hollow structure have an average particle diameter of 1 μ to 1,000 μ, a bulk density of 0.01 to 0.8 g / cm and an average wall thickness of 0.1 to 100 μ. 3. The method according to claims I and 2, characterized in that based on the volume of the hollow carbon microsphere shells 4 to 40 percent by volume Binders are used. 4. The method according to claims I to 3, characterized in that the binder is a thermosetting resin, a thermosetting inorganic material or t is a carbonizable organic material. 5. The method according to claims I to 4, characterized in that the binder is a thermosetting resin / such as a phenolic resin, furfuryl alcohol resin, epoxy resin, silicone resin, alkyd resin or an unsaturated polyester resin; a thermosetting inorganic material such as water glass, colloidal silica or clay t or a carbonizable organic material such as cellulose, starch, maltose, caramel, polyvinyl alcohol, poly-acrylonitrile, or polyvinylidene chloride is. 209820/1141 β. Process according to claims 1 or 2, characterized in that the binder is diluted with a volatile solvent when it is used. 7. The method according to claims I or 2, characterized in that the curing in the presence a curing agent is carried out. 8..Verfahren according to claims I, 2 and 7, thereby characterized in that the curing is carried out in a temperature range from room temperature to 200 ° C in a period of time from 1 minute to 24 hours. 9. The method according to claims I or 2, characterized in that the carbonization by heating the material to 300 to 100 ° C with a temperature increase of 0.5 to 10 ° C / min. is effected. 10. Carbonaceous porous article, characterized in that it is produced by a process according to claims I to 7, and consists of hollow carbon micro-spherical shells. 11. Use of the carbon-containing porous article after Claim IO as a building material for high and low temperature thermal insulation and sound insulation. 12. Use of the carbon-containing porous article after Claim IO as a filter, gas inlet plate, absorption plate or diaphragm. 209820/1141