Method for increasing oxidation reactor production capacity
AssigneeInvista North America S.A R.L.
InventorsSamuel Duncan Housley, John A. Turner
Life of this patent
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Abstract
The present invention relates to a method for increasing the production capacity of a conventional oxidation reactor for catalytic liquid phase oxidation of paraxylene by staging the oxidation reaction into a first high pressure and high solvent ratio reaction zone followed by the conventional reactor.
Claims19
A method for increasing the production capacity of a conventional back-mixed oxidation reactor for catalytic liquid phase, air oxidation of paraxylene to terephthalic acid, said method comprising:
- (a) positioning a first reaction zone upstream of said conventional back-mixed oxidation reactor;
- (b) feeding acetic acid, oxidation catalyst, paraxylene, and a supply of oxygen to said first reaction zone to form a reaction medium in which the acetic acid:paraxylene mass ratio is in the range of from 5-30:1 and the operating pressure is at least about 2,500 kPa;
- (c) limiting the uptake of oxygen within the reaction medium in said first reaction zone to a value which is less than that required for full conversion of the paraxylene present to terephthalic acid, wherein said terephthalic acid produced in the reaction medium in the first reaction zone substantially remains in solution;
- and then
- (d) feeding the reaction medium to said conventional back-mixed oxidation reactor while simultaneously reducing the pressure of the reaction medium to a value in the range of from about 500 to less than 2,500 kPa.
A method for increasing the production capacity of a conventional back-mixed oxidation reactor for catalytic liquid phase, air oxidation of paraxylene to terephthalic acid, said method comprising:
- (a) positioning a first reaction zone upstream of said conventional back-mixed oxidation reactor;
- (b) forming a feed stream comprising acetic acid and oxidation catalyst at a pressure of at least 2,500 kPa;
- (c) oxygenating the feed stream;
- (d) continuously and simultaneously feeding (1) the oxygenated feed stream and (2) paraxylene to said first reaction zone to form a reaction medium in which the acetic acid:paraxylene mass ratio is in the range of from 5-30:1;
- (e) limiting the uptake of oxygen within the reaction medium in said first reaction zone to a value which is less than that required for full conversion of the paraxylene present to terephthalic acid, wherein said terephthalic acid produced in the reaction medium in the first reaction zone substantially remains in solution;
- (f) feeding the reaction medium to a said conventional back-mixed oxidation reactor while simultaneously reducing the pressure of the reaction medium to a value in the range of from about 500 to less than 2,500 kPa.
Dependencies are inferred from the claim text.