Water Content in Waxes/Oils

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Lysander's picture
Water Content in Waxes/Oils

Hey guys
Hope everyone is well
Had a question , thought someone might know the answer

I have a sample here and basically it is eye mascara-
I'm trying to get water content on this and I'm getting inconsistent results-
There are between 52 and 54% (I have had 48% and 50% as well)
Question  1- Do you have any methods that would apply to running oil/waxes with KF?

Question  2- Do we run these warm or cold? running it warm is easier it seems
( Warm and I mean about 40 degrees C)

Question  3- Maybe I have to dissolve this sample in some sort of solvent and then run it - If that's the case; what is the back calculation procedure to find out the real sample water content?

Thanks in Advance

Lysander's picture
Hey guys

Hey guys
hope all is well with you

I believe I found the solution to my own problem
OK- Here is what can we do

You will get two vessels- One "Blank" and one "Sample"
In the "Blank" we will pour about 50 grams of 2:1 ratio of  Methanol/Chloroform-

We will get the second vessel and take 2.0 grams of your sample and add 50 grams of 2:1 ratio of Methanol/Chloroform with the stirring bar and put it on the magnetic stirring plate with plastic closed cap.

Now then;
 Get a dry syringe with needle & take out 2.5 mls of the "Blank" solution- Weigh out the sample and enter the weight on the KF keypad- Inject the solution in the KF Titration vessel and record the End Point Titration Volume. Repeat this procedure three times and get the average volumes recorded.

Take a different dry syringe with the needle and repeat the above procedure and make three injections of your sample vessel and record the end point volume.Your weight of the sample solution has to be in ball park of +/- 0.050 grams of the blank . Meaning ; Your sample and blank weights have to be very close.

Once you got the average of your three runs of blank and sample- You will proceed with the following calculation

Water % = End Point  Volume of Your Sample  Run x 5  - ( Blank Run Average x 100 x 0.05 )
                                                                                                                  Sample Weight

As far as running them warm or cold-
I still do not know the answer- I'm assuming as long as we get reproducible results and that's what it matters-