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This work presents techno-economic and greenhouse gas (GHG) analyses of an ethanol biorefinery integrating lignin conversion into eugenol and other phenolics. Catalytic hydrogenolysis assisted by isopropanol (IPA) is used to convert the lignin recovered after ionic liquid (IL) pretreatment, saccharification, and fermentation. This process was compared to a biorefinery using lignin for energy generation and simulated in SuperPro Designer. Spatial analysis was performed to determine biorefinery locations and capacities in a Mexican state with potential for lignocellulosic biomass, including corn stover, sorghum stubble, and Jatropha fruit shells. Relative to the base case, diverting 50% of lignin to phenolics decreased the ethanol cost of production significantly due to the high market value of the co-products. The minimum ethanol selling price (MESP) for this case was $2.02 gal −1 . The resulting cradle-to-gate GHG footprint of bioethanol was 21 g CO 2 -eq MJ −1 , a 78% reduction with respect to gasoline when system expansion is used for allocation. Using market value-based allocation resulted in 82% GHG reduction. Analysis of scenarios showed that a biorefinery processing 3000 t day −1 biomass and diverting 80% of lignin to phenolics can potentially yield an MESP lower than $1.5 gal −1 . To achieve this, research should target a reduction in IL input by 30% and IPA input by 40%, together with more energy-efficient separation processes. The reduction in IL and IPA can be achieved by decreasing their loading rates and increasing recycling. Sensitivity analysis showed that, 979Modeling and Analysis: Lignin valorization to eugenol and phenolic products in integrated biorefineries E Martinez-Hernandez et al.for biomass prices higher than $45 t −1 , biorefinery capacities must exceed 5000 t d −1 biomass input.

The objective of this study was to evaluate the chemical and enzymatic hydrolysis using a factorial experimental design (2 3 ) in order to obtain fermentable sugars from cellulose-based material (CBM) usually used as pet litter. In assessing chemical hydrolysis, we studied the effect of temperature, in addition to H 2 SO 4 concentration and reaction time, on the production of total sugars, reducing sugars, soluble lignin, carbohydrate profile, furfural (F), and hydroxymethyl furfural (HMF). We performed a response surface analysis and found that, at 100 ∘ C, 1% acid concentration, and 60 min reaction time, the yields of 0.0033 g reducing sugar/g biomass and 0.0852 g total sugars/g biomass were obtained. Under the above conditions, F is not generated, while HMF is generated in such a concentration that does not inhibit fermentation. We pretreated the CBM with H 2 SO 4 , NaOH, CaO, or ozonolysis, in order to evaluate the effectiveness of the enzymatic hydrolysis from the pretreated biomass, using an enzymatic cocktail. Results showed that CBM with acid was susceptible to enzymatic attack, obtaining a concentration of 0.1570 g reducing sugars/g biomass and 0.3798 g total sugars/g biomass. We concluded that acid pretreatment was the best to obtain fermentable sugars from CBM.

Energy transition toward low carbon, high sustainable and efficient generation and distribution systems will change the supply matrix of the world and create new opportunities but challenges still remain. Energy generation from biomass, or bioenergy, is one of such renewable sources and its use might be generalized in the following years. Bioenergy is a very promising strategy to provide energy not only for mobility but also for onsite places for heat and power generation. Besides, bioenergy differentiates from other renewable energies that biomass may be the source of a myriad of molecules enabling the bio-based economy and allowing the replacement in an extent of solvents, petrochemicals, and polymers produced by the petroleum industry. Biomass is generally composed of some large polymers found in nature such as cellulose, hemicellulose, proteins, starch, chitin, and lignin. The latter is a complex phenylpropanoid biopolymer conferring mechanical strength to plant cell walls and one of major spread in nature along with cellulose and chitin. Lignin has a plenty of potential uses in modern bio-based economy, from conventional paper industry uses to more challenging conversion to useful chemicals, materials, and clean biofuels. This chapter undertakes a rapid overview on lignin applications in order to describe the basis of a lignin-based economy.

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