Method for producing conductive carbides derived from waste tires

Abstract

Instead of treating waste tires as mere waste, there is a need for new technologies to recycle them into polymer materials, 3D / 4D printer materials, conductive carbides, and high-purity graphite. [Solution] The present invention extracts rubber components from waste tires by heating them in oil at 100-400°C to obtain a polymer rubber paste, and then obtains a material source through viscosity adjustment and extrusion molding. Furthermore, conductive carbides are generated by high-temperature treatment at 1000°C or higher, and high-purity graphite is obtained by plasma or laser irradiation at 1800°C or higher as needed.

Description

Technical Field

[0001] The present invention relates to a technology for producing conductive carbides, particularly graphite, using waste tires as a raw material, and to a novel production method combining oil pyrolysis, rubber pasting, viscosity adjustment, extrusion molding and high-temperature treatment. The present invention relates to a technology for decomposing and regenerating crosslinked rubber contained in waste tires by heat treatment in waste edible oil, and reusing the same as a polymer material for 3D printers and 4D printers. In particular, the present invention relates to a rubber decrosslinking treatment and a revulcanization treatment using waste salad oil as a reaction medium.

Background Art

[0002] Waste tires are generated in large quantities worldwide, and incineration, pulverization, pyrolysis and the like are known as treatment methods therefor. However, in the prior art, it is difficult to reuse waste tires as high-performance materials, and in particular, high value-added utilization as conductive carbides or graphite has been limited.

[0003] Patent Document 1 discloses an invention in which waste tire rubber is dissolved in waste salad oil and further heated to obtain carbonized rubber.

[0004] However, Patent Document 1 does not disclose a technology for utilizing the obtained carbonized rubber or the like in 3D printers or the like.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of Invention

Problems to be Solved by the Invention

[0006] There is a demand for a new technology that does not treat waste tires as mere waste, but recycles them into polymer materials, 3D / 4D printer materials, conductive carbides, and high-purity graphite.

Means for Solving the Problems

[0007] This invention involves extracting rubber components from waste tires by heat treatment in oil at 100-400°C to obtain a polymer rubber paste, followed by viscosity adjustment and extrusion molding to obtain a material source. Furthermore, conductive carbides are generated by high-temperature treatment at 1000°C or higher, and high-purity graphite is obtained by plasma or laser irradiation at 1800°C or higher as needed.

[0008] [1] A method for producing conductive carbide derived from waste tires, characterized by comprising: a rubber paste production step of heating waste tires in oil at 100 to 400°C to separate them into rubber components, steel components and carbide components, and sieving the rubber components to produce a polymer rubber paste; a viscosity adjustment step of adjusting the viscosity of the rubber paste to a desired range; an extrusion step of extruding the viscosity-adjusted rubber paste to form a filament to obtain a material source that can be used as a material for a 3D printer or 4D printer; and a high-temperature treatment step of heating the material source at 1000°C or higher to produce conductive carbide; [2] The method according to [1], characterized in that the rubber paste may be mixed with carbon black derived from waste tires, rubber carbide, steel iron powder and biomass charcoal powder as needed; [3] The method according to [1] or [2], characterized in that the viscosity adjustment step includes a step of adjusting the viscosity of the rubber paste by vulcanization; [4] The method according to any one of [1] to [3], further comprising a step of curing the filament obtained by the extrusion step at around 360°C; [5] It is known that gases such as methane, propane, and hydrogen can be produced by thermal decomposition at 500 to 700°C, and the high-temperature treatment step is carried out under conditions that do not hinder the production of the gases, as described in any of [1] to [4]. [6] The high-temperature treatment step includes a step of producing high-purity graphite by plasma or laser irradiation at 1800°C or higher, as described in any of [1] to [5]. [Effects of the Invention]

[0009] According to this invention, polymer rubber paste can be directly produced from waste tires. By adjusting the viscosity, it can be used as a material for 3D / 4D printers. Carbon black, iron powder, and carbides derived from waste tires can be used as composite materials. Conductive carbides (graphite) can be produced at temperatures above 1000°C. It can be applied to a wide range of uses, including semiconductors, automobiles, ships, aerospace, and air purifiers. [Examples]

[0010] (1) Heat the waste tires in waste salad oil at 100-400°C to separate the rubber, steel, and carbides. (2) The rubber components are sieved to obtain a polymer rubber paste. (3) The viscosity is adjusted to the desired range by vulcanization treatment. (4) The material is extruded into a filament and used as a material for 3D / 4D printers. (5) Heat to 1000-1200°C to generate conductive carbides. (6) If necessary, irradiate with plasma at 1800°C or higher to obtain high-purity graphite. [Industrial applicability]

[0011] The recycled rubber paste according to the present invention, as a polymer material containing carbon black, can be used in a wide range of fields, including 3D printer filaments, 4D printer active materials, industrial molding materials, rubber product repair materials, and building material compounds. Furthermore, it contributes to reducing environmental impact as a recycling technology for waste tires and waste cooking oil. The recycled rubber paste obtained by the present invention, as a polymer material containing carbon black, can be used in a wide range of industrial fields, including cushioning and sealing materials for semiconductor manufacturing equipment, automobile parts, marine vibration damping materials, aircraft components, structural materials for rockets and space agencies, industrial machinery components, construction materials, electrical and electronic equipment components, and even materials for 3D and 4D printers. Furthermore, as a recycling technology for waste tires and waste cooking oil, it significantly contributes to reducing environmental impact and forming a circular economy.

Claims

1. A method for producing conductive carbide derived from waste tires, comprising: a polymer rubber paste production step of heating waste tires in oil at 100 to 400°C to separate them into rubber components, steel components, and carbide components, and sieving the rubber components to produce a polymer rubber paste; a viscosity adjustment step of adjusting the viscosity of the polymer rubber paste to a desired range; an extrusion step of extruding the polymer rubber paste after viscosity adjustment to form it into a filament to obtain a material source that can be used as a material for a 3D printer or 4D printer; and a high-temperature treatment step of heating the material source at 1000°C or higher to produce conductive carbide.

2. The manufacturing method according to claim 1, characterized in that carbon black derived from waste tires, rubber carbide, steel iron powder, and biomass charcoal powder may be mixed into the polymer rubber paste as needed.

3. The manufacturing method according to claims 1 to 2, further comprising a step of curing the filament obtained by the extrusion step at around 360°C.

4. It is known that gases such as methane, propane, and hydrogen can be produced by thermal decomposition at 500 to 700°C, and the manufacturing method according to claims 1 to 2 is characterized in that the high-temperature treatment step is carried out under conditions that do not hinder the production of the gases.

5. The manufacturing method according to claims 1 to 2, characterized in that the high-temperature processing step includes a step of generating high-purity graphite by plasma or laser irradiation at 1800°C or higher.