The broader scientific impacts of the proposed research involve developing a technology to increase the efficiency in biofuel production. Biologically generated energy and chemical feedstock hold immense potential in using sustainable resources to meet both our energy, as well as industrial needs, while minimizing environmental impacts.
Most industrial processes currently use batch bioreactors due to ease of operation and control. There is an unmet need to develop a cost-effective continuous-flow, immobilized microbial bioreactor that has faster reaction kinetics, high efficiency and productivity. Stable continuous-flow bioreactors that have near constant cell densities do not require frequent inoculation and startup, and allows for consistent production of metabolites of interest, such as bioethanol. The most complex issue to be overcome in the pursuit of this goal, which is also the one issue that was not overcome in previous attempts, is to develop an immobilization material that maintains the viability of the immobilized microbial cells without hindering the metabolic pathways of the microbe. To this extent, the PI has developed a novel US Patent Pending immobilization process to form MAF materials in which both cell viability and metabolic pathways are preserved. MAF materials are thin polymeric fibrous scaffold containing microorganisms within the fibers and are formed via the process of electrospinning. These thin polymeric fibers have high rates of diffusion of nutrients and metabolites to allow microbial survival. Further, the fibers overlap each other in a completely random manner, giving rise to an open pore structure that is ideal for use in a flow reactor. This proposal aims to design, develop, characterize, and evaluate an IMBR in which the MAF material forms the key component. The use of MAF materials in an IMBR will be transformational. The central hypothesis is that such a system will be more efficient and have high productivity.
The principal objectives of the proposed research, in addition to the design and development of MAF materials based laboratory-scale IMBRs, are to: (i) evaluate and compare the efficiencies of the MAF material-based batch fermentors and IMBRs, (ii) determine the longevity and stability of microbes in the IMBRs, and (iii) optimize the MAF material characteristics such as porosity, fiber diameter, and IMBR flow rate, to increase efficiency of IMBRs.
The PI has recently developed the MAF materials via the process of electrospinning; a process that is widely used in the polymeric fiber industry and therefore makes it readily scalable for large-scale commercial use.