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The key process parameters of solid state enzymolysis for the generation of soluble sugar (SS) and bio-hydrogen production from corn stalk were optimized by the response surface methodology (RSM) based on a three factor-five level central composite design (CCD), respectively. The result showed that the optimal solid state enzymolysis condition from corn stalk was 47.7 °C, SCED of 0.054 g/g and 10.3 days for the maximum SS yield of 526 mg/g-TVS. Correspondingly, the optimal enzymolysis conditions from corn stalk appeared at 46.3 °C, SCED of 0.049 g/g and 7.5 days for the maximum hydrogen yield of 205.5 mL/g-TVS from the hydrolyzed substrate by the next dark fermentation. In addition, the bio-hydrogen production mechanism from corn stalk was preliminary investigated by XRD and SEM analyses. The results suggested that the solid state enzymolysis of substrate played a vital role in the effective conversion of corn stalk into bio-hydrogen by dark fermentation.

A hydrogen producing strain F.P 01 was newly isolated from cow dung sludge in an anaerobic bioreactor. The strain F.P 01 was a mesophilic and facultative anaerobic bacterium, which exhibited gram-negative staining in both the exponential and stationary growth phases, and a regular long rod-shaped bacteria with the size of 0.6–0.9 μm × 1.2–2.5 μm, and also could biodegrade a variety of carbohydrates such as glucose, xylose, maltose, etc. The effects of important process parameters on hydrogen producing of F.P 01 were further investigated from hydrogen fermentation of maltose by strain F.P 01, including substrate concentration, medium pH, etc. And the results showed that hydrogen production potential and hydrogen production rate from maltose of this strain F.P 01 was180 mLH 2 /g-maltose and 4.0 mLH 2 /h, respectively. The corresponding hydrogen concentration of 58–73% was also be observed. Both butyric acid and acetic acid as main by-product was left in the reactor.

Strategies were adopted to cost-efficiently produce cellulose-hydrogen by anaerobic fermentation in this paper. First, cellulase used for hydrolyzing cellulose was prepared by solid-state fermentation (SSF) on cheap biomass from Trichoderma viride. Several cultural conditions for cellulase production on cheap biomass such as moisture content, inoculum size and culture time were studied. And the components of solid-state medium were optimized using statistical methods to further improve cellulase capability. Second, the crude cellulase was applied to cellulose-hydrogen process directly. The maximal hydrogen yield of 122 ml/g-TVS was obtained at the substrate concentration of 20 g/L and cultured time of 53 h. The value was about 45-fold than that of raw corn stalk wastes. The hydrogen content in the biogas was 44–57%(v/v) and there was no significant methane gas observed.