Iowa State researchers studying slow-release fertilizer to feed crops, improve water quality


In Iowa, Iowa State University researchers may have found a slow-release fertilizer that could feed crops while protecting water quality, but they may have found one.

“We’ve calculated biochar’s incredible ability to store carbon in a small package,” said Robert C. Brown, director of Iowa State’s Bioeconomy Institute. “One day it might be valued at $200 per ton for its ability to remove carbon from the atmosphere, but currently it’s only worth about $40 per ton – the energy value of burning it as a coal substitute.”

A research team led by Brown – who’s also an Anson Marston Distinguished Professor in Engineering and the Gary and Donna Hoover Chair in Mechanical Engineering – won a two-year, $1,469,448 grant to find valuable applications for biochar. The grant is from the Biomass Research and Development Initiative, a joint program of the U.S. Departments of Agriculture and Energy.

The grant put Santanu Bakshi, an assistant scientist at the Bioeconomy Institute, to work on yet another biochar project. He’s worked with the material for most of the decade, starting as a doctoral student at the University of Florida looking into how biochar could be used to reduce copper toxicity in the soils supporting citrus groves. In another project, Bakshi showed the effectiveness of biochar in removing arsenic from drinking water.

Bakshi discovered that biochar produced from biomass pretreated with iron sulfate, an inexpensive byproduct of steel making, can adsorb to its surface up to 12 times the phosphate as biochar from untreated biomass.