Methods for producing graphite from paper

Abstract

This invention relates to a method for producing graphite from paper, the produced graphite being used as a filter material or building material. The object of this invention is to provide a cost-effective, simple, and sustainable method for producing graphite. The method involves soaking paper / waste paper, paper scraps, or paper strips in water in a suitable container for several hours, then mixing and crushing the soaked paper using a suitable apparatus until a paste or a mixture with a similar consistency is formed. A binder (e.g., sugar or starch) is added to the paste, which is then placed in a suitable mold and pressed to remove moisture, or isostatically pressed to form a pressed product. The dehydrated pressed product is then removed from the mold and carbonized in a high-temperature furnace at a temperature >1000°C, followed by graphitization at a temperature >2000°C (up to 3000°C).

Description

Methods for producing graphite from paper This invention relates to a method for producing graphite from paper, the produced graphite being used as a filter material or building material. The purpose of this invention is to provide a cost-effective, simple and sustainable method for producing graphite from paper (preferably waste paper), the produced graphite being used as a filter material or building material. To achieve the objectives of this invention, the method involves soaking paper / waste paper, paper scraps, or paper strips in water in a suitable container for several hours, then crushing the soaked paper using a suitable device until a paste or a mixture with a similar consistency is formed, and adding a binder (e.g., sugar or starch) to the paste. The paste is then placed in a suitable mold and pressed to remove moisture, or isostatically pressed to form a pressed product, followed by drying. Then, as usual, the dried pressed product can be removed from the mold and carbonized in a high-temperature furnace at a temperature >1000°C, and then graphitized at a temperature >2000°C (up to 3000°C). Of course, both carbonization and graphitization must be carried out in an environment with at least no oxygen or in the presence of an inert gas. The paper is soaked for approximately 24 hours. To ensure that the pressed products can be better bonded together after the moisture is removed and will not break after graphitization, water-soluble adhesives such as sugar or syrup can be added to the soaked paper and distributed well and evenly in the paste. An alternative is to add starch (such as potato starch, corn starch, rice starch, or the like) to a paste or a mixture with a similar consistency as a binder. One particularly advantageous practice is to dry the pressed product before further processing to reduce or avoid the release of volatile components during subsequent processing, thus preventing cracks from forming during subsequent high-temperature treatment. Drying can be carried out in an oven or dehumidifier to speed up the drying process. To produce graphite blocks, paper / waste paper, scraps, or strips are first soaked in a suitable container 1 of any size for several hours, for example, 24 hours. The soaked paper is then crushed using a suitable device 2 until a paste 3 or a mixture with a similar consistency to a paste is formed (Figure 1). Sugar or starch can be added to the paste 3 as a binder. In addition to mixers, meat grinders or extruders with cutting propellers and screw conveyors can also be used to make pastes, which can significantly increase production. Place the paste 3 in a suitable mold, and then press the paste to remove moisture, or press the paste isostatically to form a pressed product 4, as shown in Figure 2. For example, an angular mold can be used as a device for pressing a paste, wherein two opposite sides of the mold are open, while the lower opening of the mold is sealed by a sieve, perforated plate, or similar structure. An alternative is to use a top-opening mold. The pressing process can be carried out simply by pressing an appropriate punch into the corresponding mold from above, so that the pressed water can be squeezed out through a sieve, or—if a mold that is closed itself and only opens at the top—the water can be forced upwards and poured out. In both cases, the result is compact granules 4 (Figure 2). Both cases can produce densely pressed products 4 (Figure 2). To facilitate easy removal of the pressed product from the mold, the sieve should be placed only on one edge of the bottom so that the pressed product can be easily removed from the extrusion container along with the extruded product after pressing. Alternatively, you can simply flip the mold over and then remove the pressed product 4 by tapping it. Before further processing, the pressed product should be dried in air or in a suitable drying device to reduce or avoid gas release during subsequent processing. This prevents cracking during subsequent high-temperature treatment. Then, as in the usual procedure, the dried pressed product 4 can be carbonized in a high-temperature furnace at a temperature >1000°C, and then graphitized at a temperature >2000°C (up to 3000°C). Then the graphite block 5 can be used or processed as needed. Of course, both carbonization and graphitization must be carried out in an environment with at least no oxygen or in the presence of an inert gas. To ensure that the pressed products 4 can be better bonded together after the moisture is removed and will not break after graphitization, a water-soluble adhesive such as sugar or syrup can be added to the soaked paper and distributed well and evenly in the paste. An alternative is to add starch (such as potato starch, corn starch, rice starch, or the like) to a paste or a mixture with a similar consistency as a binder. A particularly advantageous practice is to pre-dry the pressed product 4 at high temperatures before further processing to reduce or avoid gas release during subsequent processing, thus preventing cracking during the subsequent high-temperature treatment. Drying can be carried out in an oven or dehumidifier to accelerate the drying process. 1: Container 2: Apparatus 3: Paste 4: Pressed product 5: Graphite block The present invention will be further described below with reference to an embodiment. The related figures are: Figure 1: Paper or paper scraps soaked in a container during the crushing process; Figure 2: The pressed product after the moisture has been squeezed out; and Figure 3: A high-density graphite block produced by the method of the present invention. 1: Container 2: Device 3: Paste

Claims

1. A method for producing graphite from paper, the graphite being used as a filter material or building material, characterized by: - ​​soaking paper in water in a suitable container; - mixing and crushing the soaked paper using a suitable apparatus until a paste is formed, and adding a water-soluble binder to the paste; - placing the paste into a suitable mold and then pressing the paste to remove moisture, or isostatically pressing the paste to form a pressed product; - drying the pressed product in an oven or dehumidifier before further processing; - carbonizing the moisture-removed pressed product in a high-temperature furnace at a temperature >1000°C, and then graphitizing it at a temperature between 2000°C and 3000°C in an oxygen-free environment or in an inert gas environment.

2. The method as described in request item 1, wherein, The paper is soaked for approximately 24 hours.

3. The method as described in request item 1, wherein, Add sugar or starch as a binder.

4. The method as described in request item 1, wherein, The added starch is potato starch, corn starch, or rice starch.

5. The method as described in request item 1, wherein, A paste is pressed using a top-opening mold, the lower part of which is sealed by a sieve or perforated plate, with a punch being pressed into the mold from above.

6. The method as described in claim 4, wherein, The perforated plate in the mold is loosely placed on one edge of the bottom of the mold.

7. The method as described in request item 1, wherein, A paste-like substance is pressed using a mold that is closed at the bottom and open at the top, with the punch being pressed into the mold from above.

8. The method as described in request item 1, wherein, Use waste paper as paper.

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