RU99117915A - METHOD FOR PRODUCING ACETIC ACID - Google Patents

Claims (8)

1. The method of liquid-phase oxidation of butane to produce acetic acid as a result of the interaction of oxygen with butane in the presence of a cobalt catalyst in a liquid reaction mixture in an oxidizing reaction zone, characterized in that the process is carried out in the reaction zone at a temperature in the range from 120 to 180 ° C. constant maintenance in the entire reaction zone of an oxygen concentration equivalent to a partial oxygen pressure of more than 2 bar and a concentration of cobalt oxidation catalyst in a liquid reaction mixture in terms of cobalt from at least 0.12 wt. % to the limit of its solubility in this liquid reaction mixture.  2. The method according to p. 1, carried out at a temperature in the range of 136-150 ° C.  3. The method according to claim 1 or 2, in which the oxygen concentration is equivalent to a partial oxygen pressure of more than 4 bar.  4. The method according to any one of the preceding paragraphs, which is carried out under a total gauge pressure of 35 bar. 5. A method of producing acetic acid, including:
(a) the interaction of oxygen and butane at a temperature in the range of 120-180 ° C in the recycle first liquid reaction mixture in the first reaction zone to produce acetic acid, wherein this first liquid reaction mixture contains a cobalt oxidation catalyst, butane, dissolved oxygen, acetic acid and water and does not contain an interface between a gas and a liquid with an upper gas phase, while at the same time constantly maintaining an oxygen concentration in the entire first reaction zone, equivalent to an acid partial pressure ode above 2 bar, and a concentration of cobalt oxidation catalyst in the first reaction mixture liquid based on cobalt of at least 0.12 wt.% to its solubility limit in the first liquid reaction mixture,
(b) withdrawing from the first reaction zone at least a portion of the first liquid reaction mixture together with entrained oxygen and supplying it to the column-type bubble reaction zone in which the second liquid reaction mixture containing the cobalt oxidation catalyst, butane, dissolved oxygen, acetic acid is located and water, and the interaction of entrained and dissolved oxygen with butane in this second liquid reaction mixture in a bubble reaction zone of a column type to obtain an additional amount of acetic acid slots, and this second liquid reaction mixture is in contact with the upper gas phase containing oxygen in a concentration that is below the lower flammability limit of the oxygen in it,
(c) withdrawing from the columnar bubble reaction zone at least a portion of the second liquid reaction mixture, isolating acetic acid and optionally other by-products contained therein, and returning the cobalt oxidation catalyst to the first reaction zone from the withdrawn mixture, and
(d) withdrawing from the bubble reaction zone of the column type the upper gas phase, recovering from it unreacted butane reagent and returning it to the first reaction zone.  6. The use of the reactor in the production of acetic acid according to any one of the preceding paragraphs, and this reactor includes two reaction zones, of which the first reaction zone is used to place a recirculating first liquid reaction mixture without an interface between a gas and a liquid with an upper gas phase, and the second reaction the zone serves to accommodate a second liquid reaction mixture with an interface between the gas and the liquid with the upper gas phase, and in the first reaction zone, it is possible to install a gas and / or liquid device and a baffle device for use in dispersing throughout this first reaction zone gas and / or liquid introduced through such an inlet device.  7. The use according to claim 6, in which the dispersion of gas and / or liquid is carried out in a radial direction relative to the axis of the gas-liquid flow exiting the inlet device.  8. The use of claim 6 or 7, wherein the diaphragm nozzle serves as an inlet to the reactor.