Nitric-acid Hydrolysis of Miscanthus giganteus to Sugars Fermented to Bioethanol

Fuxin Yang, Waheed Afzal, Kun Cheng, Nian Liu, Markus Pauly, Alexis T Bell, Zhigang Liu, John M Prausnitz (Corresponding Author)

Research output: Contribution to journalArticlepeer-review

17 Citations (Scopus)
22 Downloads (Pure)


Miscanthus giganteus (M. giganteus) is a promising feedstock for the production of bioethanol or biochemicals. Using only dilute nitric acid, this work describes a two-step process for hydrolyzing hemicellulose and cellulose to fermentable sugars. Primary variables were temperature and reaction time. The solid-to-liquid mass ratio was 1:8. No enzymes were used. In the first step, M. giganteus was contacted with 0.5 wt.% nitric acid at temperatures between 120 and 160°C for 5 to 40 min. The second step used 0.5 or 0.75 wt.% nitric acid at temperatures between 180 and 210°C for less than 6 min. Under selected conditions, almost all hemicellulose and 58% cellulose were transferred to the liquid phase. Small amounts of degradation products were observed. The xylose solution obtained from the nitric-acid hydrolysis was fermented for 96 h and the glucose solution for 48 h to yield 0.41 g ethanol/g xylose and 0.46 g ethanol/g glucose. To characterize residual solids and the liquor from both steps, nuclear-magneticresonance (NMR) spectroscopy was performed for each fraction. The analytical data indicate that the liquid phase from Steps 1 and 2 contain little lignin or lignin derivatives.
Original languageEnglish
Pages (from-to)304-314
Number of pages11
JournalBiotechnology and Bioprocess Engineering
Issue number2
Publication statusPublished - Apr 2015


  • miscanthus giganteus
  • dilute-nitric-acid hydrolysis
  • two-step process
  • fermentation
  • analysis with NMR


Dive into the research topics of 'Nitric-acid Hydrolysis of Miscanthus giganteus to Sugars Fermented to Bioethanol'. Together they form a unique fingerprint.

Cite this