A circular carbon process involves: a) reacting hydrogen and carbon monoxide to produce methane and water, b) decomposing methane into carbon and hydrogen, and c) using carbon as reducing agent and/or using carbon in a carbon-containing material as reducing agent, in a chemical process to produce carbon monoxide and a reduced substance. The methane produced in a) is used in b), the carbon produced in b) is used in c), and carbon monoxide produced in c) is used in a).

A circular carbon process involves: a) reacting hydrogen and carbon monoxide to produce methane and water, b) decomposing methane into carbon and hydrogen, and c) using carbon as reducing agent and/or using carbon in a carbon-containing material as reducing agent, in a chemical process to produce carbon monoxide and a reduced substance. The methane produced in a) is used in b), the carbon produced in b) is used in c), and carbon monoxide produced in c) is used in a).

A method for removing boron is provided, which includes (a) mixing a carbon source material and a silicon source material in a chamber to form a solid state mixture, (b) heating the solid state mixture to a temperature of 1000° C. to 1600° C., and adjusting the pressure of the chamber to 1 torr to 100 torr. The method also includes (c) conducting a gas mixture of a first carrier gas and water vapor into the chamber to remove boron from the solid state mixture, and (d) conducting a second carrier gas into the chamber.

A method for removing boron is provided, which includes (a) mixing a carbon source material and a silicon source material in a chamber to form a solid state mixture, (b) heating the solid state mixture to a temperature of 1000° C. to 1600° C., and adjusting the pressure of the chamber to 1 torr to 100 torr. The method also includes (c) conducting a gas mixture of a first carrier gas and water vapor into the chamber to remove boron from the solid state mixture, and (d) conducting a second carrier gas into the chamber.

There is provided a silicon carbide powder having a small mean particle diameter and a narrow particle diameter distribution width. A silicon carbide powder is a powder of silicon carbide (SiC) having an α-type crystal form and has a mean particle diameter of 300 nm or less. In the silicon carbide powder, a ratio D90/D10 between a particle diameter D10 and a particle diameter D90 is 4 or less, the particle diameter D10 being a particle diameter at which the cumulative particle volume from the small particle diameter side in a volume-based cumulative particle diameter distribution reaches 10% of the total particle volume and the particle diameter D90 being a particle diameter at which the cumulative particle volume from the small particle diameter side in the volume-based cumulative particle diameter distribution reaches 90% of the total particle volume.

The invention discloses a method for producing silicon carbide from waste circuit board cracking residue, belongs to the field of comprehensive utilization of waste circuit board cracking products, and particularly relates to a method for high-valued utilization of non-metal components in waste circuit board cracking residue. The method mainly comprises the following steps: rolling and crushing, vibration sorting, ultrafine pulverization and electro-separation, quantitative batching, microwave sintering and discharging and grading. Compared with the prior art, rolling crushing is adopted to replace traditional shearing crushing, microwave sintering is adopted to replace a traditional Acheson smelting furnace, the effects of being easy to operate, saving energy and reducing consumption are achieved, the production efficiency is greatly improved, and the production cost is reduced. A brand-new method for obtaining high-purity silicon carbide by partially replacing anthracite and quartz sand with cracked coke and silicon dioxide in waste circuit board light plates or epoxy resin cracking residues is adopted, and high-value utilization of waste resources is achieved. The method has the characteristics of simple and feasible process, low manufacturing cost and wide adaptability, and is beneficial to improving the economic benefit and social benefit of enterprise production.

A method of preparing a high-purity silicon carbide (SiC) crystal, and more specifically, to a method of preparing high-purity SiC having an extremely low impurity content in an excellent yield and in large quantities. The method including preparing a reactor containing a reaction chamber; heating the conductive heating element in the reaction chamber; mixing a silicon precursor, a carbon precursor, and a carrier gas; injecting the mixed gas into the reaction chamber, depositing SiC on the conductive heating element and harvesting the deposited SiC crystals.

A method for manufacturing a silicon carbide powder according to the embodiment includes forming a mixture by mixing a silicon (Si) source containing silicon with a solid carbon (C) source or a C source containing an organic carbon compound; heating the mixture; cooling the mixture; and supplying hydrogen gas into the mixture.

The present application provides a method, a equipment and a system for producing a silicon-containing products by using a silicon sludge which is produced by a diamond wire cutting silicon material. The method of the present application mainly utilizes a high oxide layer on the surface of a silicon waste particle produced during diamond wire cutting. The characteristics are such that the surface oxide disproportionates with adjacent internal elemental silicon to form silicon monoxide to be removed in a vapor to achieve a physical chemical reaction with a metal, a halogen gas, a hydrogen halide gas or hydrogen to form a high value-added silicon-containing products. The process realizes the large-scale, high-efficiency, energy-saving, continuous and low-cost complete recycling of diamond-wire cutting silicon waste.

The present application provides a method, a equipment and a system for producing a silicon-containing products by using a silicon sludge which is produced by a diamond wire cutting silicon material. The method of the present application mainly utilizes a high oxide layer on the surface of a silicon waste particle produced during diamond wire cutting. The characteristics are such that the surface oxide disproportionates with adjacent internal elemental silicon to form silicon monoxide to be removed in a vapor to achieve a physical chemical reaction with a metal, a halogen gas, a hydrogen halide gas or hydrogen to form a high value-added silicon-containing products. The process realizes the large-scale, high-efficiency, energy-saving, continuous and low-cost complete recycling of diamond-wire cutting silicon waste.