Process Research on Separate Hydrolysis and Fermentation(SHF) and Simultaneous Saccharification and Fermentation(SSF) of Ethanol Production by Lignocellulose

[ Objective] The research aimed to explore the efficiency of ethanol production under the optimal conditions of separate hydrolysis and fermentation （SHF） and simultaneous saccharification and fermentation （SSF）. [ Method ] Under the optimal conditions of hydrolysis and fermenta- tion, SHF and SSF process were designed respectively. SHF process was conducted under the optimal conditions of hydrolysis and fermentation separately, while SSF process was carried out at the optimum temperature of hydrolysis and fermentation. [ Result] In SHF process, the efficiency of ethanol production was similar during both supematant and mixture fermentation, and yeast was more active during the mixture fermentation. In SSF process, the efficiency of ethanol production was higher at 35 ℃, and the production of xylose was higher than that in hydrolysis process. [ Conclusion] Under the experimental conditions, the efficiency of ethanol production during simultaneous saccharification and fermentation was higher than that during separate hydrolysis and fermentation.

Enhanced biomass densification pretreatment using binary chemicals for efficient lignocellulosic valorization

Many effective pretreatment methods (such as dilute acid, dilute alkali, ionic liquids, etc.) have been developed for lignocellulose upgrading, but several defaults of low working mass, high sugar loss and extra cost of solid-liquid separation and water washing hinder their large-scale applica- tion in industry. Besides, the valorization of lignin-rich residue from pretreated biomass after hy- drolysis or fermentation greatly contributes to the economy and sustainability of lignocellulosic biorefinery, which is usually underestimated. This study developed a densification pretreatment with binary chemicals (densifying lignocellulosic biomass with sulfuric acid (SA) and metal salt (MS) followed by autoclave treatment ((DLCA(SA-MS)), which was conducted under mild con- dition (121 ℃) with a biomass working mass as high as 400 kg/m^(3) . The DLCA(SA-MS) biomass achieved over 95% sugar retention, 90% enzymatic sugar conversion and a high concentration of fermentable sugar (212.3 g/L) with superior fermentability. Furthermore, bio-adsorbent de- rived from DLCA(SA-MS) biomass residue was highly adsorptive and suitable for dyeing wastew- ater treatment, providing a feasible and eco-friendly method for lignin-rich residue valorization. These findings indicated that DLCA(SA-MS) pretreatment enables the full-component utilization of biomass and boosts the economic viability of lignocellulosic biorefinery.

Greener approach to the comprehensive utilization of algal biomass and oil using novel Clostridial fusants and bio-based solvents

A greener method has been tested to utilize algal biomass as a feedstock to produce bio-oil in addition to acetone,butanol,and ethanol(ABE)products.Various hydrolysis treatments were used prior to fermentation including combination of thermal,chemical,and enzymatic,which resulted in maximum sugar release of 27.78 g/L.Bio-based terpenes was used instead of common toxic chemicals together with Clostridial fustants to produce bio-alcoholic fuels.Protoplast fusion technique were used to produce the novel Clostridia fusants(C.beijernickii+C.thermocellum and C.acetobutylicum+C.thermocellocum).Fused strains were then subjected to UV radiation for strain enhancement.Final fusansts showed clear improvement in thermal stability and resistance to biobutanol toxicity.Fermentation experiments showed maximum biobutanol final production of 7.98 g/L using CbCt versus 7.39 g/L using CaCt.Oil extraction from virgin algae was tested using a green,bio-based approach using ter-penes with ultrasonication and green Bligh and Dyer method,separately.In preliminary study on algal biomass,the combinations of ultrasonication followed by the green Bligh and Dyer have resulted in oil yield of 46.27%(d-limonene)and 39.85%(p-cymene).Oil extraction from an algae sample following fermentation using the combined extraction method resulted in significantly higher oil yield of 65.04%.