Abstract: The invention provides systems and processes for concentrating acetic acid and acetic anhydride streams. The systems allow operation of equipment used for such concentrations in two or more modes of operation. At least one mode is intended to produce a concentrated or purified acetic acid stream. At least one other mode is intended to produce a concentrated or purified acetic anhydride stream.

Abstract: The invention provides systems and processes for concentrating acetic acid and acetic anhydride streams. The systems allow operation of equipment used for such concentrations in two or more modes of operation. At least one mode is intended to produce a concentrated or purified acetic acid stream. At least one other mode is intended to produce a concentrated or purified acetic anhydride stream.

Abstract: Processes for producing aromatic dicarboxylic acids are disclosed, the processes including a step of combining in a reaction medium a dialkyl aromatic, a solvent comprising water and a saturated organic acid having from 2-4 carbon atoms, and an oxygen-containing gas, at a temperature from about 125° C. to about 155° C., in the presence of a catalyst composition comprising cobalt, manganese, zirconium, and bromine, wherein the weight ratio of cobalt to manganese in the reaction mixture is from about 10 to about 400. The processes provide improved conversion, while reducing the formation of carbon oxides and other by-products.

Abstract: In a liquid phase carbonylation process for the production of acetic anhydride by reacting a feed stream which includes methyl acetate, methanol and carbon monoxide using a Group VIII metal-containing catalyst, and preferably a rhodium containing material, a liquid reaction product is continuously withdrawn from the carbonylation zone and fed to an evaporation/separation zone for separating volatile constituents of the reaction from the non-volatile constituents which, includes a portion of the Group VIII metal catalyst from the carbonylation reactor. The Group VIII metal catalyst is contacted with a gas stream which includes hydrogen for a period of from about 0.001 seconds to about 200 seconds as it is being returned to the carbonylation zone.