By Rick Da Tech
You see it all over the internet, in videos and websites, people making small batches of biodiesel in a food processing blender. The practice goes back to the beginning of homebrew biodiesel and it’s time for it to stop. Food processors and blenders were designed to process food. Methanol, lye, and biodiesel are very aggressive chemicals that attack rubber and seals in different ways. In fact we find that most of the seal material that is good for biodiesel, will not hold up to methanol. The reverse is also true. There are only a few seals that will hold up to biodiesel, methanol, and lye. So what happens is the seal in the bottom of the blender pitcher or container eventually starts to leak. When it does methanol drips onto the electric motor below. The electric motors used in food processors and blenders use brushes and spark heavily. It’s inevitable that if methanol or even methanol laced biodiesel is dripped into sparky central that a fire will occur.
I’ve heard time and time again, horror stories about blenders catching on fire when making a small batch. The lucky ones intuitively understood the risk and had the blender outside in a fireproof area. The unlucky ones melted down a blender on their wife’s kitchen counter top, not a good thing.
So what is the alternative? Use either a magnetic stirrer or shake by hand. The smaller the batch, the easier it is to mix. A one liter batch made in a glass jar or HDPE container and physical shaking can be used without any problems. www.kitchen-biodiesel.com show one way of making a small batch without using a blender.
Do yourself a favor and don’t make biodiesel in a food processing blender.