Processes for oxidizing hydrocarbyl moieties to carboxylic acids and anhydrides

摘要

Continuous processes are provided for the partial oxidation in the vapor phase over a heterogeneous catalyst in a reaction zone of hydrocarbyl reactant to produce carboxylic acids or anhydrides wherein at least a portion of unreacted hydrocarbyl reactant is returned via a cyclic loop to the reaction zone. The partial oxidation generates carbon oxides which are used as ballast gas in the cyclic loop. The carboxylic acids or anhydrides are removed from the cyclic loop by condensation. Purification of the products can be by stripping lights and then dehydrating the carboxylic acid or anhydride product removed from the cyclic loop.