Monday, April 30, 2012
Napoleon Ballroom C-D, 3rd fl (Sheraton New Orleans)
The quality of biodiesel can vary depending on the molecular structures of esters constituents or due to contaminants from the raw material, of manufacturing process or formed during storage of biodiesel. This paper proposes a method for detecting the level for degradation in samples of biodiesel using the enzyme lipase as bioelement of biosensor systems that allows more direct monitoring of quality using of the simple, quick and specific method . Beyond that, it is able to provide rapid results, ease of data processing, analysis provide a low cost and, in most cases, a portable instrument. To perform work was used the commercial enzyme from Candida rugosa, to evaluate the efficiency of lipase activity applied to samples of biodiesel, as well as in samples of vegetable oils used in its production, together with an electrode of pH for non-aqueous solutions, used as transducer. The commercial lipase enzyme from Candida rugosa was tested in the form free and immobilized. The system (enzyme/electrode) showed optimum response within 15min at pH 8,75 and 37ºC. The current (mV) was in proportion to concentration of ester in the range 350 – 17500 mM acid free. A good correlation (R2 = 0,9912) was found and showed a good performance for potentiometric detection of triglycerides in oils and biodiesel. An potentiometric method was then developed for determination of degradation in samples of biodiesel employing lipase Enzymatic Biosensor for Biodiesel`s Quality Monitoring. Acknowledgements: CNPq and FAPERJ for financial support