A STRUCTURED APPROACH TO DESIGN AND OPERATION OF BIOTRANSFORMATION PROCESSES

A structured approach to design and operation of biotransformation (bi oconversion) processes, based on previous case studies, has been devel oped. This requires knowledge of the key characteristics of a biotrans formation which determine the constraints on process selection. The ap proach is illustrated for five biotransformations, two enzymic and thr ee microbial. Some generic problems such as low water solubility and v olatility of reactants, reactant and product toxicity have been identi fied. The microbial oxidations of toluene and fluorobenzene to toluene cis-glycol and fluorocatechol respectively by Pseudomonas putida have been used to illustrate how these constraints may be overcome by addi tion of tetradecane as a second liquid phase, use of a membrane oxygen ator and introduction of in situ product removal.