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Researchers at the University of Wisconsin-Madison have developed a new two-step process for converting biomass into biofuels that starts with untreated biomass. The findings were published February 11 in the Journal of the American Chemical Society. The key step in the process is the first step, where cellulose is converted into 5-hydroxymethylfurfural (HMF), which can be converted into other high value-added chemicals. There are also some research teams that can convert glucose or fructose into 5-hydroxymethylfurfural. This process will directly convert biomass into 5-hydroxymethylfurfural in a one-step process. Raines and doctoral student Joseph Binder invented a special dissolving system that can dissolve long-chain sugar molecules in plant material cellulose. It can dissolve cotton balls composed entirely of cellulose. It is simple, safe, low-cost, and non-corrosive. This dissolution system has been patented. Another difficult problem to solve in cellulose utilization is lignin. In plant cell walls, lignin acts like glue, with lignin molecules acting like a protective scaffolding to protect the cellulose. However, the chemical dissolving agents used by Raines and Binder have small molecules that can pass through lignin molecules, breaking up the cellulose and converting it into HMF. In the second step, HMF is converted into 2,5-dimethylfuran (DMF). In these two steps, the conversion rate of biomass to biofuel is 9%, that is, 9% of the cellulose in corn stover is finally converted into biofuel. “There are still some problems in converting HMF into DMF in the second step and need to continue to be improved," Raines said. He is very excited that DMF can be used as biofuel. DMF has the same calorific value as gasoline, is not prone to water, can use existing fuel transportation infrastructure, and has now begun to be used as a gasoline additive. In addition to straw, this process can also be widely used to process other cellulosic biomass such as wood chips.