Production process of carbon tetrafluoride
1. Carbon tetrafluoride can be produced by reaction of carbon with fluorine, or reaction of carbon monoxide with fluorine, or reaction of silicon carbide with fluorine, or reaction of fluorite with petroleum coke in an electric furnace, or reaction of methane difluorodichloride with hydrogen fluoride, or reaction of carbon tetrachloride with silver fluoride, or reaction of carbon tetrachloride with hydrogen fluoride. The reaction between carbon tetrachloride and hydrogen fluoride is carried out in a high-temperature nickel tube filled with chromium hydroxide. After the reaction, the gas is washed and alkaline washed to remove the acid gas, and then frozen, and the water in the gas is removed with silica gel. Finally, the finished product is obtained through rectification.
2. Said in advance to take silicon carbide powder of 5 ~ 10 g and 0.1 g of elemental silicon powder, placed in the nickel plate, after making a good contact with silicon and silicon carbide, the nickel plate into the monel alloy tube in the reaction, the reaction tube ventilation with fluorine, fluorine and elemental silicon first reaction, reaction heat, fluorine start and silicon carbide on reaction, such as access to the volume of dry nitrogen to dilute fluorine and the reaction to continue, produce gas by liquid nitrogen cooling the nickel trap condensation, then slowly after gasification, it through the gas bottle containing sodium hydroxide solution to remove silicon tetrafluoride, then by silica gel and phosphorus pentoxide drying tower to get the final product.
3. Activated carbon and fluorine were prepared by fluorination reaction. In the reactant containing activated carbon, the high concentrated fluorine gas is slowly passed into it, and the reaction temperature is controlled by heating, fluorine supply rate and cooling of the reactant. After dedusting the product, the impurities such as HF, CoF2, SiF4, CO2, etc. are removed by alkaline washing, and then the crude products with a content of about 85% can be obtained by dehydration. The crude products were introduced into the low-temperature distillation kettle for batch rough distillation. By controlling the rectification temperature, O2, N2 and H2 were removed to obtain high-purity CF4.