| |
Summary of the Problem:
The production of BioDiesel from triglycerides (edible oils such as soybean oil) involves the production of by-product glycerol (same as glycerin), a very viscous water-soluble product that is sparingly soluble in BioDiesel, an organic liquid. Removing all the contaminating glycerol as well as other water-soluble impurities such as free fatty acids and salts of free fatty acids is either slow OR expensive AND ALWAYS reduces the overall yield of BioDiesel.
Summary of the Solution:
An alternative technology exists for extracting water-soluble components from organic liquids, but this technology has never, to our knowledge, been applied to BioDiesel. In this technology, hydrophobic porous membranes can be used to prevent bulk mixing of the two phases yet facilitate contact and mass transfer of species between the two phases. Hydrophobic BioDiesel wets the membrane pores by capillary action but remains on one side of the membrane. Water held on the other side of the membrane contacts the BioDiesel phase by physically touching the BioDiesel held in the pore, and preferentially water-soluble species such as free fatty acids migrate from the BioDiesel phase through the pore and into the water phase. The two phases are circulated tangentially to the membrane surface to enhance mass transfer.
In the case of BioDiesel purification, this membrane-mediated extraction can replace traditional “mix and shake” methods of contacting the two phases (BioDiesel and water phases). Yield loss of BioDiesel to the water phase will be less. Also, expensive high-speed rotating centrifugal contactors are replaced by membrane contactors that require only modest pumping of the phases tangential to the membrane surface.
|
| |
Significant progress can be made during the course of a summer project. The project runs in parallel with some business development activities that my partner and I are pursuing. |
| |
The successful applicant will be an engineering or physical sciences major and preferably have some bona fide experience in the laboratory. Applicants should have keen attention to detail and an interest in applying chemical engineering science to a meaningful problem with commercial potential. |
| |
The Research Project:
Membrane contactors employing hydrophobic membranes are commercially available and are used primarily in solvent extraction applications. At Tufts, we have direct experience with these contactors in a water-based/kerosine system and have already assembled a bench scale prototype purifier that could be used to process liter quantities of BioDiesel in our laboratory in the Science and Technology Building. We have not, however, conducted the proof-of-principle experiments to show this system can work as proposed in the novel BioDiesel purification scheme discussed above. Once the proof-of-principle experiments have shown the utility of the purification scheme a systematic study is required to characterize the engineering parameters that would guide successful scale-up of the process technology.
In the longer term, we desire to construct pilot scale production facilities for BioDiesel in the Science and Technology Building and attract industrial partnerships interested in commercializing the new purification technology.
|