Campus food waste become campus soap

When students who produce sustainable energy generate a “waste product,” they don’t wash their hands of it. They wash their hands with it.

Members of the soap group of the Illinois Biodiesel Initiative (IBI), are experimenting with recipes to create functional and marketable soap from glycerin, a by-product of the reaction that produces biodiesel. The IBI is a registered student organization at the University of Illinois. Members are working to improve upon a sample of liquid dish soap that they gave to the Ikenberry Dining Hall earlier this year, as well as developing new soaps to sell to other outlets on campus.

The Initiative works under the guidance of Joe Pickowitz, environmental engineer at the Illinois Sustainable Technology Center (ISTC), a division of the Prairie Research Institute at the University of Illinois.

IBI is an independent division of the campus’s Engineers without Borders group. Its main project is to collect waste vegetable oil from campus dining halls every week and convert it into biodiesel. The Initiative then sells the biodiesel back to the university through the campus’s facilities and services department to use in its vehicles.
Founded in 2006, IBI has made soap production a crucial part of its goal as a sustainable student group since fall 2011. Because only about 80 percent of the biodiesel reaction’s yield is fuel, the soap group is in charge of utilizing the remaining glycerin.

In January, the soap group gave 45 gallons of liquid soap to the dining hall, which Pickowitz calls “the test bed for the whole project.” There, it was used as a prewash in the dish rooms—only a few hundred feet from where the soap’s parent oil may have been used to fry a batch of chicken wings.

The soap helped clean the dishes, but it left behind a residue on the dishes and in the dishwashing machine, said chemical engineering sophomore and Soap Production Officer Stephanie Roupas. The group is addressing this concern by testing and reformulating batches of liquid soap and said they hope to have a new batch ready for the dining hall before summer break. The soap group is preparing other samples for university housing as part of a proposal to replace the hand soap in dormitory bathrooms with a product that is sustainably manufactured right on campus.

Along with liquid soap, the group has been testing different recipes for solid soap. The form of the final soap product depends on which strong basic compound is used as a catalyst in the biodiesel reaction. While potassium hydroxide produces liquid soap, sodium hydroxide produces solid soap.

In the solids preparation lab at ISTC, Soap Research Lead Olivia Webb, who is a freshman in agricultural and biological engineering, demonstrates one problem with the solid soap. A recent batch has the consistency of Play-Doh, and it is difficult to remove samples from the pan.

“See, it’s not supposed to do that—where it’s sticking like that,” she says. “This is still useable as soap. It’s just not as marketable.”

Still working toward a perfect batch of soap, the group overcomes defects like this by carefully experimenting with new ingredients, different cooking times, and varying ingredient ratios.

Marketability may be difficult for the raw version of the soap, Webb says, because it’s brown and smells a bit like a fry cook after a day’s work. In an effort to make their product more appealing, Webb says they will re-batch the pan of bar soap to make it harder, so they are able to sell it on campus. They are also adding a scent to the sample that they will present to university housing to make it more attractive. Because most commercial dyes and scents are not sustainable, students have begun to color the soap with environmentally friendly products, such as algae, and are looking into using natural, essential oils rather than fragrances.

While they are developing their soap to be a more marketable product, Webb says they are not planning to sell it anywhere beyond campus this early in the game, as they strive for both environmental and economic sustainability.

“It would be a lot easier to start in the university so we have something to say [to consumers], ‘Our soap actually works,’” she remarks. “And it’s also easier to sell to people in the university because your shipping and packaging costs are low.”