chemsample-caspie-discussion

A general discussion of the results we obtained for each trial product (if more than one were obtained), and conclusions we were able to draw about the procedure itself.
 * __ Caspie Discussion ~ __**


 * __Student A + B__**

//Product #1// You can tell from our NMR that all the reactants were broken down. This means that there was a 100% conversion using the amount of catalyst that we experimented with. The double "horn" peak on the IR spectrum (~3387 cm-1) shows that there was some amino groups in the product. This could be a result of impurities from the waste oil that we used to start with. Another sign of impurities from this waste oil showed up on the NMR around 5.3. This is the shift for unsaturated hydrocarbon, which could easily have resulted from hydrocarbon strands in the singletwaste oil. The at 3.5 showed that we did get the product of esters from the transesterification process. However, the intensity of the peak was not as high as for other groups, which means our yield was not as high as it might have been if we used corn or soybean oil to start. In the future, it would be a helpful process to somehow purify the waste oil before running the biodiesel synthesis. Since we have NMR and IR of what could possibily be in there (unsaturated hydrocarbons/amino groups) a series of new tests should be run to try and remove these items and increase our yield.

//Product #2// The second product had a very similar spec reading as the first. There was still the presence of amino groups and unsaturated hydrocarbons. However, the intensity of the products peak in the NMR was higher. This means that less catalyst is actually more effective for forming product. This is good news for future studies, because less materials can be used to create biodiesel.

__**Student C**__

//Product #1 (only product)// Looking at my product NMR I was able to tell (as Sarah / Adrian were) that all of my reactants broke down in the presence of 60 % catalyst - meaning, nearly 100 % conversion with 60 % catalyst. The IR spectra further confirmed these suspicions. This was surprising to me given that our initial expectations were that there may be some limit to the amount of catalyst used and the resulting conversion of reactants. However, apparently this was not the case - given that what was initially thought to be 20 % catalyst was actually 60 % catalyst (give or take according to measurement error). The amount of yield I obtained was also a little surprising. I expected such a high level of catalyst to either hinder the reactionary process, or at the very least interfere with product formation in higher amounts. However, I obtained nearly 80 % product yield! And, given that our groups part to the experiment seemed less significant than say the variance in temperature, it was exciting to see that presence of excess catalyst did not interfere greatly with the reaction process.

Now, looking at some of the results from the other groups involved, it seems to me that no one variable we altered played any extremely crucial role to the process. That is, our variance of catalyst did not alter our results with any significant detail. Comparing the results for example from 60 % and 45 % catalyst, there was not a significant difference in either the percent yield, or (for example) the NMR and / or IR spectra for each product. In fact, the two were quite similar. The same was true for the variable temperatures. However, I believe that our lab was able to obtain the most significant yields using waste oil, when compared to corn and soy (essentially clean, refined oils). This is exciting in the sense that this was a primary objective of the Caspie Module - to use already used oil in a recycle-like fashion to produce a product from what is otherwise useless waste!


 * __Student D + E__**

There were a total of two experiments performed. Our goal was to use only 10% catalyst, but due to a miscalculation with the molarity of the waste oil, we actually ended up using 30%. We were able to correct this by performing a second experiment using the amount we obtained from the second calculation. These different amounts of catalyst used didn't make that much of an impact on both the yield and IR & NMR charts.

Looking at the reaction above you can see how the molecule triglyceride, is able to successfully be broken down into a combination of molecules. The highest peak observed in the NMR chart was the ester that you see in brackets. This molecule is derived from the waste oil using the catalyst that was given to us, along with methanol. Although there were certain indication of impurities such as the appearance of peaks that weren't apart of the ester, and the IR chart showing an absorbance around 3500cm-1, which was then identified as an amine. If given the opportunity to do this experiment again I would filter the waste oil before putting in into the MARS microwave.

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