Patent ID: 7399882

Claim:
A process for producing terephthalic acid, said process comprising: (a) introducing a predominately gas-phase oxidant stream comprising molecular oxygen into a reaction zone of a bubble column reactor; (b) introducing a predominately liquid-phase feed stream comprising para-xylene into said reaction zone via a plurality of feed openings, wherein said reaction zone has a maximum diameter (D), wherein at least two of said feed openings are vertically spaced from one another by at least 0.5D, wherein at least a portion of said feed stream enters said reaction zone at an inlet superficial velocity of at least 5 meters per second; and (c) oxidizing at least a portion of said para-xylene in a liquid phase of a multi-phase reaction medium contained in said reaction zone to thereby produce crude terephthalic acid, wherein said reaction medium has a maximum height (H), a maximum width (W), and an H:W ratio of at least 3:1.