Sorry for another long brutal delay in posting here! I’ve been up to no good, although my recent projects have not been technically legal (thanks to some antiquated Prohibition-era bylaws) so I’m a little thin for content.
Back in December I met up with my friend Lee for an experiment in homemade biodiesel production. I never got around to posting about this so here is my photoblog of the process.
Biodiesel is a vegetable oil based diesel fuel that can typically run in an vehicle with a diesel engine. It can be mixed 50/50 with petrodiesel (B50) and run in any vehicle without modifications, or you can run it straight (B100) with simple mods. Biodiesel can be produced from a variety of waste oils and is becoming increasingly mainstream and petro-fuel gets more and more expensive.
Old ceiling fan motor that I bought at Active Surplus for $12. This will become the processor for the fuel mix.
This is all the gear used in this project. Unico vegetable oil, methanol, potassium hydroxide, ~3L glass vase, 600 mL beaker, 1L mason jar, 250 mL measuring cup, digital scale accurate to 0.01g, thermometer ranged -10C to +200C, motor processor.
Obviously you can use waste vegetable oil to make biodiesel, but this adds some complications to the process. For our first attempt I wanted to keep things simple. Store bought oil is clean and has no water content.
Two sketchy chemicals! 99.9% methanol (available at Canadian Tire) and 99% pure KOH potassium hydroxide (available online at www.canwax.com). Both are highly toxic. The former will cause optic nerve damage and make you blind. Be careful
This is our biodiesel processor rig. Cleaning it under hot water here. We need to maintain a temperature of 55C as we’re mixing the fuel; easiest way to do this is mix it in a stockpot on the stove.
Hockey pucks at the bottom of the stock pot, which shield the glass vase from heat blast from the stove burners.
Safety first! Wear a lab coat, eye protection and rubber gloves. Designate all containers that come into contact with KOH or methanol (we used a biohazard sticker) and never use them for food products again.
Measure 200 mL methanol in beaker. Transfer this to 1L mason jar.
Based on 99% purity (or so we’re told) measure out 4.91 g of KOH potassium hydroxide. In hindsight we should’ve been a series of titration tests to determine the exact mass of KOH needed. Also I’m not convinced it was 99% pure.
4.90g, close enough!
You could pay $300 for a professional lab scale… or you could pay $30 for a drug dealer scale. Try to get one accurate to 0.01g.
Add the KOH into the masor jar with the methanol. I used the cutting board here to shield myself from possible explosions, but sadly it was pretty boring.
Seal the mason jar tightly. Then shake it a bunch and let it rest 10-20 minutes. Wait until all the KOH dissolves. This creates a new solution called methoxide.
Measure out 1L of vegetable oil.
Pour vegetable oil into a pot and heat it to 55C.
Mix the 55C oil and the methoxide.
Lee is rigging up the motor to the top of the vase.
This is the biodiesel processor. We used chopsticks as the support system for the motor (it’s ghetto but it works). Hockey pucks to shield the vase from the flame. Kept the water heated at 55C to maintain temperature in the vase.
Hockey tape is perfect for securing the chopstick supports. Secure the supports together, then seal them to the vase.
Firing up the motor.
Trying to maintain 55C in the water. Obviously this is difficult but I figure it’s close enough.
Just a few minutes after we started. The mix is still very cloudy.
Still cloudy after about 20 minutes.
After 30-40 minutes the mixture started clearing.
After 1 hour it was mostly translucent.
This is the final mix after coming out of the processor. Let it sit overnight.
After waiting a while a red layer of glycerin formed at the bottom. This means it worked!
We ran some quality tests later which showed the fuel is pretty poor quality, and probably would not burn in a motor. Not surprising for a first attempt. There are several ways we could improve this process, most notably:
- Build a closed processor unit that is not exposed to open air.
- Titration tests on the oil to determine proper amount of KOH needed.
- Make sure we know exact purity of KOH.
- Better system to maintain 55C temperature in processor.
Moreover I need a vehicle or some sort of engine to actually use the fuel in. Once I have such a vehicle I will look into ways of improving this process, and will post whatever I come up with here.