Dark fermentative hydrogen production following the sequential dilute acid pretreatment and enzymatic saccharification of rice husk

Ralph Rolly Gonzales, Sang Hyoun Kim

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This study examined the effect of sequential dilute acid hydrolysis and enzyme saccharification conditions of rice husk on hydrogen (H2) fermentation. The rice husk was hydrolyzed using dilute H2SO4 and then further enzymatically hydrolyzed with various concentrations (0.1, 0.25, 0.5, 0.75, and 1.0 mg protein mL−1) of Celluclast 1.5 L®. The sequential pretreatment significantly enhanced sugar recovery, up to 174% for 1.0 mg mL−1 concentration of the enzyme. Increasing the concentration of enzyme slightly increases sugar recovery. While the production of furfural and 5-hydroxymethylfurfural occurred during dilute acid hydrolysis, it was not observed during enzymatic saccharification. At the following H2 fermentation of the hydrolyzates, H2 yield was improved up to 150% by using the dilute acid and enzymatic hydrolyzate as substrate, as compared when only dilute acid hydrolyzate was used. The highest H2 yield of 473.1 mL H2 g−1 rice husk was achieved with enzyme concentration of 0.75 mg protein mL−1.

Original languageEnglish
Pages (from-to)27577-27583
Number of pages7
JournalInternational Journal of Hydrogen Energy
Issue number45
Publication statusPublished - 2017 Jan 1


All Science Journal Classification (ASJC) codes

  • Renewable Energy, Sustainability and the Environment
  • Fuel Technology
  • Condensed Matter Physics
  • Energy Engineering and Power Technology

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