This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).
0932511 Ho
Recent advances in enzymatic synthetic methods using biocatalysts have lead to environmentally friendly production methods of beta-lactam antibiotics. These methods have been limited in their industrial use due to the difficult separation of the desired antibiotic from other components of the reaction mixture. The development of a simple and easy to operate separation process for antibiotic recovery from aqueous solutions and fermentation broths would eliminate a major drawback of enzymatic antibiotic production. The research proposed will focus on the recovery of antibiotics from fermentation broths using supported liquid membranes with strip dispersion. The proposed process will recover and concentrate antibiotics in a simple manner, while providing long-term stability, which is a requirement for industrial use. This process combines extraction and back-extraction, carried out in 2 separate steps in conventional extraction processes, into a one-step membrane process. This one step process not only simplifies the separation process, but also eliminates the needs for the extractor and the back extractor. This process also overcomes the thermodynamic solubility limitation of solvent. Thus, this process will have both significant capital and energy savings. The recovery of Cephalexin will be studied extensively on a laboratory scale to determine important factors in the separation process. The understanding of the mass transfer mechanism involving interfacial complexation reactions and complex diffusion and the development of mathematical models that describe the mass transfer suitable for scale-up are also goals of this work. Once the recovery of Cephalexin is fully understood, similar processes for other antibiotics will be developed.
Supported liquid membranes with strip dispersion have never been used in comprehensive studies involving the recovery of antibiotics or biochemicals. The proposed separation scheme provides an efficient and stable separation process. Long-term stability is the key obstacle in commercialization of liquid membrane processes. This research not only is of a great scientific interest in the fundamental understanding of the transport mechanism but also may provide an improved separation scheme of significant technological importance. We believe that it represents a significant contribution to expanding the scientific knowledge and understanding in the science and technology of antibiotic separation/recovery. This work also provides the education of the students involved with such kind of research.
The resulting work will have immediate impacts on the industrial production of antibiotics. The proposed one-step process will save energy, reduce costs, eliminate toxic solvents, and operate at higher efficiencies compared to current industrial processes used for antibiotic separation. These improvements will foster the industrial use of enzymatic synthetic methods for antibiotic production. This process also has potential for the effective separation of other organic acids from fermentation broths such as lactic acid, citric acid, and propionic acid and for the recovery of other organic compounds including bio ethanol and butanol.