A method for recycling spent carbon cathode of aluminum electrolysis includes the following steps: (1) crushing and sieving spent carbon cathode, to obtain carbon particles; (2) mixing the carbon particles with a sulfuric acid solution, to obtain a slurry A, and then performing pressure leaching, to obtain a slurry B; (3) evaporating and concentrating the slurry B until a mass percentage of water is lower than 8%, to obtain a slurry C; (4) adding concentrated sulfuric acid to the slurry C to obtain a slurry D, then roasting the slurry D at 150-300° C. for 0.5-10 h, and then roasting at 300-600° C. for 0.5-8 h, to obtain the roasted carbon; and calcining the roasted carbon at a high temperature, to obtain the purified carbon, or mixing the roasted carbon with a leaching agent, and performing leaching, filtering, and washing, to obtain the purified carbon.

A method for recycling spent carbon cathode of aluminum electrolysis includes the following steps: (1) crushing and sieving spent carbon cathode, to obtain carbon particles; (2) mixing the carbon particles with a sulfuric acid solution, to obtain a slurry A, and then performing pressure leaching, to obtain a slurry B; (3) evaporating and concentrating the slurry B until a mass percentage of water is lower than 8%, to obtain a slurry C; (4) adding concentrated sulfuric acid to the slurry C to obtain a slurry D, then roasting the slurry D at 150-300° C. for 0.5-10 h, and then roasting at 300-600° C. for 0.5-8 h, to obtain the roasted carbon; and calcining the roasted carbon at a high temperature, to obtain the purified carbon, or mixing the roasted carbon with a leaching agent, and performing leaching, filtering, and washing, to obtain the purified carbon.

The inventive concepts disclosed relate to the production of green and blue hydrogen from hydrocarbons using visible light (from a laser, lamp or sun) and defect-engineered boron-rich photocatalysts. We demonstrate that the environment of the B atoms in the lattice can be tuned to favor the dehydrogenation of desired hydrocarbons on reaction sites under visible light. In addition to the hydrogen produced in gas form, carbon atoms are captured by the catalyst and form structures of potential higher value for future applications. Further study of the dark carbonaceous product revealed a graphitic aspect of the material. These findings highlight a new functionality of 2D materials for visible light-assisted capture and conversion of hydrocarbons, with great potential for green hydrogen production—i.e, hydrogen produced from renewable energy and without the release of CO or CO.sub.2.

The inventive concepts disclosed relate to the production of green and blue hydrogen from hydrocarbons using visible light (from a laser, lamp or sun) and defect-engineered boron-rich photocatalysts. We demonstrate that the environment of the B atoms in the lattice can be tuned to favor the dehydrogenation of desired hydrocarbons on reaction sites under visible light. In addition to the hydrogen produced in gas form, carbon atoms are captured by the catalyst and form structures of potential higher value for future applications. Further study of the dark carbonaceous product revealed a graphitic aspect of the material. These findings highlight a new functionality of 2D materials for visible light-assisted capture and conversion of hydrocarbons, with great potential for green hydrogen production—i.e, hydrogen produced from renewable energy and without the release of CO or CO.sub.2.

A method for producing an artificial graphite material for a lithium ion secondary battery negative electrode, including at least a step of performing a coking treatment on a raw material oil composition by performing a delayed coking process to generate a raw coke composition, a step of performing a heat treatment on the raw coke composition to obtain a heat-treated raw coke composition, a step of crushing the heat-treated raw coke composition to obtain heat-treated raw coke powder, a step of graphitizing the heat-treated raw coke powder to obtain graphite powder, and a step of crushing the graphite powder, in which a volatile content of the heat-treated raw coke powder is less than 3.71%, and a true density of the heat-treated raw coke powder is greater than 1.22 g/cm.sup.3 and less than 1.73 g/cm.sup.3.

A method for producing an artificial graphite material for a lithium ion secondary battery negative electrode, including at least a step of performing a coking treatment on a raw material oil composition by performing a delayed coking process to generate a raw coke composition, a step of performing a heat treatment on the raw coke composition to obtain a heat-treated raw coke composition, a step of crushing the heat-treated raw coke composition to obtain heat-treated raw coke powder, a step of graphitizing the heat-treated raw coke powder to obtain graphite powder, and a step of crushing the graphite powder, in which a volatile content of the heat-treated raw coke powder is less than 3.71%, and a true density of the heat-treated raw coke powder is greater than 1.22 g/cm.sup.3 and less than 1.73 g/cm.sup.3.

Disclosed is a system and method related to removal of carbon from carbon dioxide via the use of plasma arc heating techniques. The method involves generating C atoms and H atoms from C.sub.xH.sub.y. The method involves generating graphite and H.sub.2 from the C atoms and H atoms, and extracting the graphite. The method involves quenching the H.sub.2 with C.sub.xH.sub.y. The method involves receiving, at a generator, the quenched the H.sub.2 and C.sub.xH.sub.y and generating electricity. The method involves generating a concentrated stream of H.sub.2 from the quenched H.sub.2 and C.sub.xH.sub.y. The method involves receiving CO.sub.2 and the concentrated stream of H.sub.2 and generating C, O, and H atoms. The method involves receiving the C, O, and H atoms and generating graphite, wherein the graphite is extracted. In the hydrocarbon C.sub.xH.sub.y: x is an integer 1, 2, 3, . . . , and y=2x+2.

Disclosed is a system and method related to removal of carbon from carbon dioxide via the use of plasma arc heating techniques. The method involves generating C atoms and H atoms from C.sub.xH.sub.y. The method involves generating graphite and H.sub.2 from the C atoms and H atoms, and extracting the graphite. The method involves quenching the H.sub.2 with C.sub.xH.sub.y. The method involves receiving, at a generator, the quenched the H.sub.2 and C.sub.xH.sub.y and generating electricity. The method involves generating a concentrated stream of H.sub.2 from the quenched H.sub.2 and C.sub.xH.sub.y. The method involves receiving CO.sub.2 and the concentrated stream of H.sub.2 and generating C, O, and H atoms. The method involves receiving the C, O, and H atoms and generating graphite, wherein the graphite is extracted. In the hydrocarbon C.sub.xH.sub.y: x is an integer 1, 2, 3, . . . , and y=2x+2.

A process of controlling the morphology of graphite in a process for the production of graphite, the process comprising: contacting at elevated temperature, a metal-containing catalyst with a hydrocarbon gas to catalytically convert at least a portion of the hydrocarbon gas to hydrogen and carbon; wherein the temperature is between 600° C. and 1000° C. and a pressure between 0 bar(g) and 100 bar(g), and wherein both the temperature and the pressure are set within predetermined value ranges to selectively synthesise graphitic material with a desired morphology.

A process of controlling the morphology of graphite in a process for the production of graphite, the process comprising: contacting at elevated temperature, a metal-containing catalyst with a hydrocarbon gas to catalytically convert at least a portion of the hydrocarbon gas to hydrogen and carbon; wherein the temperature is between 600° C. and 1000° C. and a pressure between 0 bar(g) and 100 bar(g), and wherein both the temperature and the pressure are set within predetermined value ranges to selectively synthesise graphitic material with a desired morphology.