A method for producing acetic anhydride that includes operating a high shear device at a shear rate of greater than about 20,000 s−1, wherein the high shear device is configured with a rotor and a stator; forming in the high shear device an emulsion having a liquid catalyst dispersed in an acetic acid solution; introducing the emulsion into a reactor at conditions suitable for the production of ketene; and reacting at least some ketene with acetic acid to produce acetic anhydride.