I broke a graduated cylinder today.

Yep, I just broke one of the great graduated cylinders that was kindly donated to us by the EHS office. It was the 250mL cylinder, so I'm especially bummed. But I have to admit, that is the only thing that has gone wrong today. And who knows, maybe we'll happen upon another 250mL graduated cylinder soon.
After performing small batches of biodiesel last week using different amount of potassium hydroxide (KOH), we determined that an additional 5g or 7g KOH was not enough for our waste vegetable oil (WVO). We get WVO from various places around the student center, and it is not great quality, which means we need more KOH. So this week, we are testing different reactions using an additional 9g and 11g KOH.
During normal biodiesel processing, we typically perform two reactions. We perform the first reaction using 80% of the total amount of potassium methoxide needed. After the biodiesel and glycerol separate, we remove the glycerol and add the other 20% of the methoxide. By removing the glycerol, we remove one of the products, so adding more methoxide will push the reaction to completion. For more information on the 80/20 biodiesel production method, click here.
An alternative to the 80/20 version, is the 80/20-90/10 version, which uses the same principles to push the reaction to completion, uses different combinations of methanol and potassium hydroxide to make methoxide. For this version, the first reaction uses methoxide with 80% the total amount of methanol, and 90% of the total amount of KOH, while the second reaction uses methoxide with 20% of the total amount of methanol, and 10% of the total amount of KOH (hence its name). For more information and examples of both, click here.
See our updated procedure here.

We will continue processing normal-sized batches next week utilizing the conclusions of these weeks experiments, which will hopefully improve the efficiency of our processor. On the left is a simple filter we developed at the beginning of the summer to filter out larger food particles in our WVO. I tested it yesterday, and it definitely did its job preventing the pump from getting clogged. However, the part was 3-D printed, and it fit over the PVC pipe very tightly, and a small nudge when hanging it back up broke it in half. Since it was a succes, we will machine another one out of aluminum this time.

So I've broken a couple of things this week, but still, everything has been going very well overall. A few things to look forward to this month: performing 27/3 tests on our biodiesel samples from these past two weeks, attempting methanol recovery on glycerol from our next batch (maybe we'll make soap!), building relations with local businesses to collect more oil, and showcasing at the Women's Technology Program on July 19th!