Pilot-scale fermentation of aqueous-ammonia-soaked switchgrass

Applied Biochemistry and Biotechnology
Asli IsciRobert P Anex

Abstract

Aqueous-ammonia-steeped switchgrass was subject to simultaneous saccharification and fermentation (SSF) in two pilot-scale bioreactors (50- and 350-L working volume). Switchgrass was pretreated by soaking in ammonium hydroxide (30%) with solid to liquid ratio of 5 L ammonium hydroxide per kilogram dry switchgrass for 5 days in 75-L steeping vessels without agitation at ambient temperatures (15 to 33 degrees C). SSF of the pretreated biomass was carried out using Saccharomyces cerevisiae (D(5)A) at approximately 2% glucan and 77 filter paper units per gram cellulose enzyme loading (Spezyme CP). The 50-L fermentation was carried out aseptically, whereas the 350-L fermentation was semiaseptic. The percentage of maximum theoretical ethanol yields achieved was 73% in the 50-L reactor and 52-74% in the 350-L reactor due to the difference in asepsis. The 350-L fermentation was contaminated by acid-producing bacteria (lactic and acetic acid concentrations approaching 10 g/L), and this resulted in lower ethanol production. Despite this problem, the pilot-scale SSF of aqueous-ammonia-pretreated switchgrass has shown promising results similar to laboratory-scale experiments. This work demonstrates challenges in pilot-scale fermentations w...Continue Reading

References

May 4, 2000·Journal of Agricultural and Food Chemistry·A Demirci, A L Pometto
Apr 25, 2001·Applied Biochemistry and Biotechnology·M KurakakeT Komaki
Jun 3, 2005·Applied Biochemistry and Biotechnology·Tae Hyun Kim, Y Y Lee
Jun 3, 2005·Applied Biochemistry and Biotechnology·Hasan AlizadehBruce E Dale
Oct 21, 2006·Biotechnology and Bioengineering·Young S DoAlan A DiSpirito
Apr 17, 2008·Applied Biochemistry and Biotechnology·Asli IsciRobert P Anex
Jan 1, 1983·Biotechnology and Bioengineering·B MaiorellaC R Wilke

❮ Previous
Next ❯

Citations

Apr 22, 2010·Applied Biochemistry and Biotechnology·Scott W Pryor, Nurun Nahar
Apr 27, 2010·Applied Biochemistry and Biotechnology·Chinnadurai Karunanithy, Kasiviswanathan Muthukumarappan
Nov 18, 2015·Applied Microbiology and Biotechnology·Rossana LiguoriVincenza Faraco

❮ Previous
Next ❯

Related Concepts

Related Feeds

Biofuels (ASM)

Biofuels are produced through contemporary processes from biomass rather than geological processes involved in fossil fuel formation. Examples include biodiesel, green diesel, biogas, etc. Discover the latest research on biofuels in this feed.