• LyeDiscount
• Conclusion

Through the use of the ¹³CNMR, the extracted oils were able to be characterized and compared against each other. The ¹³CNMR spectra of the oil from a soap which had the minor oil added at trace had no meaningful difference between the oil from a soap where the minor oil was added before trace. The fact that there is no difference between the extracted oils suggests that it does not matter whether or not the oil is added before trace or at trace because saponification occurs during the cooking phase rather than the mixing phase. The important range for deciding the composition of the fatty acid in the extracted oil was the 125ppm to 135ppm range.<xref linkend="F6"/> shows the spectrum of 90% Palm Oil and 10% Castor Oil. That range corresponds to the double bonds present in the oil. For Castor Oil, for which ricenoleic acid is the major fatty acid, there are two peaks in the region at 125ppm and 133ppm. In Palm Oil, which has two double bonds, there are peaks which can be found at 127ppm, 129ppm, and 130ppm. Each of the spectra acquired from the extracted oils showed a larger 127-130ppm range and two much smaller peaks at 125ppm and 133ppm respectively which suggests that, in the case of both palm/castor and palm/grapeseed oil soaps, most of the oil extracted is palm oil.<xref linkend="T1"/> Shows an NMR spectrum for 90% palm / 10% castor oil.

<figure id="F6"><title>90% Palm Oil 10% Castor Oil CNMR Spectrum</title> <mediaobject><imageobject><imagedata fileref="90palmoil10castoroilCNMR.jpg" format="JPG" scale="20"/></imageobject></mediaobject> </figure>

In order to determine the amount of ricenoleic acid in a sample, ¹³CNMR was run on series of known mixtures to determine the ratio between the peak at 125ppm(double bond in ricenoleic acid) and 14ppm(the terminal methyl group present in all fatty matter). First a peak ratio for 99% ricenoleic acid, ordered from Aldritch, was obtained. After the peak ratio was obtained for 99% ricenoleic acid, a series of known samples were prepared, 100% palm oil, 100% castor oil, 75% palm oil 25% castor oil, 50% palm oil 50% castor oil, and 25% palm oil 75% castor oil. The peak ratios were plotted using Excel and the calibration curve had an R2 value of .9938. <xref linkend="F4"/> Shows the calibration plot of percent ricenoleic acid vs. percent castor oil. The data suggests that it is appropriate to be able to compare the peak at 125ppm vs. the peak at 14ppm and multiply it by the constant obtained in the 99% ricenoleic acid sample, 120.83, to determine the total ricenoleic acid content of a sample. This was done for each of the extractions and it was found to be that there was an average of 2-4% ricenoleic acid leftover after the extractions. The extractions which yielded higher % ricenoleic acid can be attributed the increased soapy matter in the sample. The extraction was not as good and therefore more of the extraction was soap than the others.

<figure id="F4"><title><superscript>13</superscript>C-NMR Spectral Analysis Data for Castor Oil</title> <mediaobject><imageobject><imagedata fileref="castoroilpercent.pdf" format="PDF" scale="50"/></imageobject></mediaobject> </figure>

<table id="T1"><title>% Ricenoleic Acid From Each Extraction</title>

</table>

Another section of the ¹³CNMR spectrum was analyzed to determine the content of the glyceride molecules present. The range from 170ppm to 180ppm gives properties of the glyceride molecules and the relative area of the peaks can be used to determine the amount of each glyceride present. The peak at 174ppm represents the carboxylic acid group from a monoglyceride, the peaks in the 173ppm represents the carboxylic acid group from a diglyceride and the peaks in the 172 range represents the carboxylic acid group from a triglyceride. The peak at 178ppm is the free fatty acid. From the spectra acquired from the extractions, most of the glycerides are mono- and di-glycerides. As expected, the spectrum of the pure fatty acid(ricenoleic acid) shows only one peak at 178ppm.<xref linkend="R6"/>

<bibliomixed id="R6">Hamilton, R.J., <citetitle>Lipid Analysis in Oils and Fats</citetitle>, 1998. 93-117</bibliomixed>

In order to determine the amount of linoleic acid in a sample, ¹³CNMR was run on series of known mixtures to determine the ratio between the peak at 129ppm(double bond in linoleic acid) and 14ppm(the terminal methyl group present in all fatty matter). First a peak ratio for 99% linoleic acid, ordered from Aldritch, was obtained. After the peak ratio was obtained for 99% linoleic acid, a series of known samples were prepared, 100% palm oil, 100% grapeseed oil, 75% palm oil 25% grapseed oil, 50% palm oil 50% grapeseed oil, and 25% palm oil 75% grapeseed oil. The peak ratios were plotted using Excel and the calibration curve had an R2 value of .9758. The data suggests that it is appropriate to be able to compare the peak at 129ppm vs. the peak at 14ppm and multiply it by the constant obtained in the 99% ricenoleic acid sample, 80.775, to determine the total ricenoleic acid content of a sample. This was done for each of the extractions and it was found to be that there was an average of 16-19% linoleic acid leftover after the extractions. This procedure was repeated for coconut/olive oil soap samples, where it was found to be that there was an average of 21% oleic acid leftover after the extractions.

<xref linkend="T2"/> summarizes the results from the palm/grapeseed oil soap studies.

<xref linkend="F5"/> shows the calibration curves generated from ¹³C-NMR Spectral Analysis for the three different set of oil combinations. Such calibration curves would enable soap makers to quickly determine relative fatty matter composition of finished soaps.

The results from this experiment can be very useful for soap makers who waste a lot of time and effort and soap by adding the minor oil at trace. The percent (%) yield of the soap is always higher when the minor oil is added before trace because more of the soap is poured into the mold when it reaches trace, instead solidifying on the walls of the mixing apparatus. The research could prove to save soap makers money because they would get more out of their materials and would have less waste.

<table id="T2"><title>Summary of Results (Palm/grapeseed oil soaps)</title>

</table>

<xref linkend="F5"/> shows the calibration curves generated from ¹³C-NMR Spectral Analysis for the three different set of oil combinations. Such calibration curves would enable soap makers to quickly determine relative fatty matter composition of finished soaps.

<figure id="F5"><title>Combined <superscript>13</superscript>C-NMR Spectral Analysis Data</title> <mediaobject><imageobject><imagedata fileref="combinedoilvsacidpercent.pdf" format="PDF" scale="50"/></imageobject></mediaobject> </figure>