Chinquapin Biodiesel

I must preface this post with the comment that I have only had one year of experience with biodiesel and am still very much a newbie.  However, given the stated goals of our BP A+ for Energy grant, I felt it important to include a post on sustainability and biodiesel.  There are two items I could discuss under this heading: (1) the sustainability of biodiesel as a viable alternative liquid energy source, and (2) sustainable practices when making biodiesel.  I’m going to discuss our efforts at the school to incorporate the later.

Most of what I have learned about the environmental impact of making biodiesel (and about biodiesel in general) has come from William Kemp’s great book Biodiesel: Basics and Beyond. I will admit that I was one of the many naive tinkerers who was caught up in the rhetoric of homebrew biodiesel.  Every website I visited mostly reinforced the idea that making biodiesel was a simple procedure that nearly anyone could accomplish.  If you delve deeper into various biodiesel forums, you can obtain a little better idea of potential issues and complications that aren’t advertised by those trying to sell you overpriced processor kits.  However, despite the prevalence of hyped advertising/rhetoric, the biodiesel community is largely comprised (from my experience) with a lot of helpful people that are trying to spread their knowledge and the benefits of biodiesel.

Where there are shortcuts, there will be people who take them, and biodiesel production is no exception.  Kemp addresses these shortcuts as “Myth Buster” sections in his book and does a thorough and convincing job of debunking these shortcuts.  Biodiesel has two inputs that are harmful to humans and the environment: methanol and sodium or potassium hydroxide.  I won’t go into much detail here except to say that ensuring that these harmful inputs don’t become harmful outputs somewhat complicates the biodiesel process.  Any unreacted methanol has to be recovered and any wash water that has been contaminated with the NaOH or KOH base used in the reaction has to be neutralized with an acid prior to disposal.  While there are fairly simple methods for accomplishing these tasks, most biodiesel homebrewers I’ve encountered don’t include these steps.

In stressing the harmful nature of some of the chemical inputs to the students, they were naturally curious about any harmful byproducts created in the process.  Wonderfully, biodiesel and its byproducts are amazingly benign as long as you recover any excess methanol and neutralize your wash water.  We were sure to include a discussion of these issues with the students involved in the project, and as our processing continues over the years we will continue to emphasize the importance of environmental sustainability over simplification of the process.   The specifics of how we employed methanol recovery and wash water neutralization in our process will be included in future video posts.