America is the top producer of corn in the world, and approximately 90 million acres of land here are used to grow this grain. Most of the corn in the U.S. is used for animal feed and unfortunately, a lot of the corn plant is not nutrient-dense and goes to waste. This month, engineers at the University of Riverside found a way to incorporate the waste from corn production and use it to filter and treat water.
This leftover biomass from corn production is called corn stover can be used as emergency livestock feed, left in the fields to replenish soil, or converted to biofuel. A lab at UC Riverside focuses on upcycling waste products like biomass back into the economy and decided to focus on additional applications for corn stover. The UC Riverside lab found that corn stover could be turned into activated carob, also known as activated charcoal, by charring it. Activated carbon is commonly used to filter and treat water because it contains millions of microscopic pores that can absorb water and filter out toxins.
The lab experimented with multiple ways of processing the corn stover into activated charcoal, and through hydrothermal carbonization, the biochar had a high surface area and large pores capable of filtering high amounts of pollutants. To test the upcycled corn stover, the lab added vanillin, a water pollutant produced by the vanilla industry, to water, and filtered it through the corn stover activated carbon. It was found that activated carbon was able to absorb 98 percent of vanillin from the water.
Upcycling food waste is all the rage right now, and last year Whole Foods predicted upcycled food to be a major trend in 2021. Some food waste is used to make new food products, while other food waste (like corn stover) is used to make commercial products. Agraloop uses sugar cane bark, pineapple leaves, and hemp stalks to create natural fibers for textile production. Researchers at the University of Toronto Scarborough discovered that they could turn waste oil sourced from McDonald’s fryers into a high-resolution, biodegradable 3D printing resin.
Approximately 366 million metric tons of corn is grown in the U.S. each year, and this results in a lot of leftover corn stover. UC Riverside lab’s discovery is a viable and useful option for unproductive biomass, but the lab did not say if it has plans for a commercial application of this discovery.