10-12: Thermochemical hydrolysis of stover from white corn: a parametric study

A parametric study was performed to evaluate the thermochemical hydrolysis (TH) of stover from white corn (S-WC) with the aim to find the conditions that increase the release of xylose, but with the concomitant low formation of furans (furfural and hydroxy-methyl-furfural). White corn is widely produced in Mexico for human consumption. The study was performed using: 15% w/w milled S-WC and an autoclave or a biomass digester (for the temperature study). Thermochemical treatments above 140°C generate a dehydration of pentoses and hexoses producing a relative high concentration of furans and a drastic reduction in soluble sugars. No significant increase in the hydrolysis of xylan was obtained above 8 to 12 minutes of TH when 2% of H₂SO₄ was used at 130°C. Furthermore, furans concentration increased directly with the time of TH and using 4-8 minutes allow obtaining the lowest concentration of these compounds. Similar concentrations of soluble sugars (in average (g/L): xylose 33.4, glucose 7.9, and arabinose 4.6) where obtained with 2 to 4% H₂SO₄, with the lowest concentrations of total furans (0.4 g/L) at 2% H₂SO₄.