So what in heaven’s name are we going to do about all this glycerol?
Also known as glycerin, glycerol is a major co-product of biodiesel. For every 10 pounds of biodiesel produced, about one pound of glycerol is created. With a little quick math, we can figure out just how deep we’re in with this glycerol glut. 450 million gallons of biodiesel were produced in 2007, which left us with 45 million gallons of glycerin. Considering that the National Biodiesel Board is expecting 60 new plants with a production capacity of 1.2 billion gallons of biodiesel to come online by 2010, we find ourselves inching toward 100 million+ gallons of glycerin annually.
Obviously, as we push toward a national mindset of sustainable development, we shouldn’t revert to our usual mentality and expect the problem to just go away. Problems with waste rarely do disappear, and they generally show up in some unwelcome locale, such as our drinking water, as we’ve discovered in the past. Currently, the disposal of surplus glycerol is performed by incineration, but we can never be too sure of the environmental health effects of such industrial scale operations, no matter how contained they may purport to be. At the very least, wouldn’t it be nice to find a way to make better use of this byproduct?
Actually, that’s not too far out of the realm of possibility. What’s great about glycerol is that we actually have an opportunity to take something useless, and physically convert it into something valuable – something for which there is a known demand. In other words, if someone gives you a cup of raw glycerol, don’t get too flustered about sending them any thank-you notes. It’s only after you’ve taken that substance and put it through any number of catalytic processes that you’ve got a real moneymaker, since glycerol can be converted into a number of useful, profitable chemicals.
For example, it can be transformed into propylene glycol, a common ingredient in a variety of resins, lubricants, cosmetics, paints, detergents, and antifreeze that, until now, has been produced from propylene oxide, a petroleum-based intermediate. It seems a no-brainer then that, instead of incinerating our extra glycerol, biodiesel producers should be finding value for it somewhere in their supply chain or selling it to help satisfy the current global annual demand for 4.5 billion pounds of glycerol.
It turns, out that this idea is catching on pretty well in the biodiesel industry. Last spring, Ashland Inc. and Cargill announced a joint venture into the world of biobased chemicals and chose as their first project producing high-grade propylene glycol from that persistent glycerol co-product. Furthermore, a consortium called “The Glycerol Challenge” was launched to find different ways to convert glycerol into specialty chemicals. The group’s members, including the University of Cardiff, Cardiff, U.K., and Vertellus Specialties in Indianapolis, Indiana, announced their intentions to expand its scope as soon as possible, seeking to add biodiesel and chemical manufacturers, as well as catalyst and engineering companies to their alliance.
In addition, researchers are continuously working to improve the practice of transforming leftover glycerol into commercial chemicals. Researchers at Rice University, for example, have developed a special strand of the E. coli bacterium that can efficiently ferment glycerol to produce succinate, a high-demand feedstock that is used in everything from solvents and plastics, to airplane deicers, drugs and food additives. Pursuing the ecological ideal of cradle-to-grave continuity in the production process, chemical industry giant Dow has been working with monopropylene glycol derived from renewable resources, and has been publicizing its entry into the world of “sustainable chemistries.”
In light of all the work being done with glycerol, it seems that this ubiquitous co-product has great potential for commercial success. Hopefully, we’ll continue with some intensive R&D and find a decent, productive, even lucrative use for our overabundance of this material. We are a nation of innovators, and we’re far too thrifty to let such a prime resource literally go to waste.
Abby Schwimmer can be reached by email at abby@biobasednews.com