COMPARISON OF EFFICIENCIES OF HOLLOW TUBES AND HOLLOW ZONES BIOCATALYTIC REACTORS FOR THE ENZYMATIC-HYDROLYSIS OF BENZYLPENICILLIN TO 6-AMINOPENICILLANIC ACID

The comparative efficiencies of two special biocatalytic reactors desi gned to handle gel-like immobilized biocatalysts, the hollow tubes and the hollow zones reactors, have been assessed for the performance of the hydrolysis of benzylpenicillin to 6-aminopenicillanic acid and phe nyl acetic acid by an immobilized penicillin amidase preparation. On t he basis of the efficiency factor eta 15/35, representing the ratio of activity expressed in the reactor at the end of 15 minutes in relatio n to the activity loaded in the reactor, and on the conversion achieve d at the end of a given time close to that required to attain conversi ons near those required in industrial operation the hollow tubes react or revealed to be slightly superior to the hollow zones reactor. The a pplication to the conversion data obtained in both reactors of the alp ha, beta kinetic model derived by Cardoso and Costa [1] also gave evid ence of the superior performance of the hollow tubes reactor. The infl uence of the linear velocity on the final conversion achieved for the hollow tubes reactor was investigated allowing the conclusion that fro m a velocity across the reactor of at least about 17.6 cm min(-1) the final conversion lime is independent of this parameter. The applicatio n of the alpha, beta kinetic model to the conversion data obtained in the hollow tubes reactor for different linear velocities also supporte d this conclusion. Although the kinetic behaviour of the conversion re action for linear velocities higher than 17.6 cm min(-1) varied with t he linear velocity the final conversion was not affected by this param eter.