US4GREENCHEM aims to design a biorefinery concept for the complete valorization of lignocellulosic biomass that is energy- and cost- efficient and based solely on green technologies. The concept combines mechanical pretreatment of the substrate with the aid of ultrasound to overcome its recalcitrance and disrupt inhibitors with mild CO2 hemicellulose degradation and with the enzymatic recovery of sugars and technologies for the valorization of the byproducts released in the process. Aim of the Project- Develop ultrasound (US) pretreatment that effectively disrupts the lignocellulosic matrix.- Further degrade lignocellulose with CO2 technologies to maximize release of sugars as main targetproducts of the process.- Develop purification and conversion strategies for lignin-based products, in order to maximize the material valorization of the biomass components.- Valorize the solid residues of the product for energy.- Optimize the yield and reduce by 50% the cost of enzymatic hydrolysis of cellulose fibers.- Test for fermentability of the sugar fraction- Propose effective integration and upscaling to strategies pilot scale through the experienced industrial partners involved in the project.- Perform a thorough analysis of the outcomes of the proposed combination of technologies to evaluate the potential economic and environmental impacts and compare the proposed concept to existing technologies on the market and being currently developed.