METHOD FOR OXIDATIVE HALOGENATION AND METHOD OF PRODUCING HALOGENATED C PRODUCT

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FIELD : chemistry. SUBSTANCE : method for oxidative halogenation involves bringing C1 reacting hydrocarbon selected from methane, halogenated C1 hydrocarbon or mixture thereof, into contact with a halogen source and an oxygen source in a reactor in the presence of a catalyst. Molar ratio of the C1 reacting hydrocarbon to the halogen source in the raw material for the reactor is greater than 23/1; or molar ratio of the C1 reacting hydrocarbon to the oxygen source in the raw material for the reactor is greater than 46/1; or in both raw materials for the reactor, the molar ratio of the C1 reacting hydrocarbon to the halogen source is greater than 23/1 and the molar ratio of the C1 reacting hydrocarbon to the oxygen source is greater than 46/1. Contact takes place under conditions of the method which are sufficient for obtaining a halogenated C1 product, having at least one extra halogen substitute compared to the reacting hydrocarbon. Conditions of the method include temperature higher than approximately 375°C and lower than approximately 700°C and pressure higher than approximately 14 psia (97 kPa) and lower than approximately 150 psia (1034 kPa); the catalyst contains a halide of a rare-earth element or an oxyhalide of a rare-earth element and the atomic ratio of the rare-earth element to iron and copper is greater than 10/1, provided that when cerium is present in the catalyst, at least one other rare-earth element is also present in the catalyst, where cerium is present in the catalyst in amount less than approximately 10 atomic % of the total amount of the rare-earth components. The invention also relates to a method of producing a halogenated C1 product, involving : (a) feeding a stream of a halogen source into a reactor containing a catalyst, where the catalyst contains a halide of a rare-earth element or an oxyhalide of a rare-earth element, and the atomic ratio of the rare-earth element to iron and copper is greater than 10/1, provided that when cerium is present in the catalyst, at least one other rare-earth element is also present in the catalyst, where cerium is present in the catalyst in amount less than approximately 10 atomic % of the total amount of the rare-earth components; (b) cutting the flow of the halogen source to the reactor; (c) adding a mixture into the reactor, where the mixture contains a C1 reacting hydrocarbon selected from a group comprising methane, a halogenated C1 hydrocarbon or mixture thereof, and an oxygen source, such that the concentration of the halogen source in the said stream is less than 0.5 vol. % and molar ratio of the C1 reacting hydrocarbon to the halogen source is greater than 23/1, under conditions of the method sufficient for obtaining a halogenated C1 product, having at least one extra halogen substitute compared to the reacting hydrocarbon, where conditions of the method include temperature higher than approximately 375°C and lower than approximately 700°C and pressure higher than approximately 14 psia (97 kPa) and lower than approximately 150 psia (1034 kPa); (d) cutting the flow of the mixture containing the C1 reacting hydrocarbon and the oxygen source to the reactor and (e) repeating steps (a) to (d) in a varying way. EFFECT : high efficiency, complete conversion of a halogen source and an oxygen source, avoiding catalyst deactivation. 3 tbl, 4 ex