chemsample-caspie-methods

Below is the general procedure applied to each of the three Chem Kid sub groups.
 * __ Caspie Method(s) ~ __**

We first calculated the proper amount of catalyst to be used ... Whether that be 5 %, 10 %, or 20 %. Then, we translated that calculation into a proper weight of catalyst for the reaction(s). 5.0 grams of waste oil were placed into aa Erlenmeyer flask (along with the catalyst). Methanol was added to give a total volume of 10.0 mL in our reaction vessels. This mixture was then transferred into a microwavable vessel, and stirred with a pipette(s) carefully (pictures below).

Our vessels were then put into the MARS microwave for 20 minutes at 140 deg C. Looking at the pictures below indicates the steps that lead up to this. First you must tighten the vessel, then hand it to your instructor to place into a rotating disc with numbers that you and your partner will be assigned.



The pictures below show you the difference in color due to the reaction taking place within the microwave. Very cool!


 * [[image:IMG00094-20100408-1159.jpg width="240" height="180"]] ||
 * BEFORE ||


 * [[image:IMG00095-20100408-1211.jpg width="304" height="227"]] ||
 * AFTER ||

Once the vessel is out of the microwave, our vessel contents were transferred into a graduated cylinder along with 25.0 mL of cold DI water. 25mL of hexane were then added to the vessel in order to remove any remaining product. Both the contents of the graduated cylinder and hexane filled vessel were transferred into the separatory funnel, and gently shaken. The organic and aqueous layers were then allowed to settle. Below you can see the separation we observed: top layer is organic / bottom is aqueous.

Our aqueous layer was then extracted (shown above in the second picture), and tested for pH until removal yielded a pH 7 (neutral). The extraction process was repeeated until this neutral pH was obtained.

Once the desired pH of the aqueous layer was achieved, we collected our remaining organic layer and place it into a 50mL Erlenmeyer flask, and washed it with Sodium Sulfate (drying it thereafter with Calcium Chloride).

Finally, we preweighed 50.0 mL round bottom flasks and evaporated our solution via a rotary evaporator unit. The weight of the round bottom flask subtracted from the total product containing weight after evaporation gave us our amount of Biodiesel product (recovered from waste oil).



Analysis of Product(s) ~ __** After successfully completeing the preparatory phase of the lab, the next obvious step we took was to put our products through experimental analysis. Doing this would give us a good indication as to whether or not significant yields had been obtained for our desired diesel product. Therefore, each product (along with experimental yield) was put through the processes of IR, and NMR.
 * __

IR Protocol NMR Protocol

Using the information we gathered from each of these processes, we were then able to formulate some opinions and conclusions as to what occurred during the reaction processes. And, most importantly, what variables and constants were significant (or, insignificant) factors in the reaction process.

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