The ButaNexT project aims to demonstrate the techno-economic feasibility of the conversion of two sustainable lignocellulosic feedstocks (wheat straw and miscanthus) available at EU level, into biobutanol through the integration of different technology developments. The project has ended recently and the main achievements of the consortium have been the following: (1) design, construction and operation of a micronizing pilot prototype for controlled biomass particle size production up to 0.5 mm with a more reduced energy consumption and able to be scalable to industrial size; (2) development of a flexible and easy to adapt two-step fractionation process based on the combination of the micronizing prototype with a continuous thermochemical pretreatment; (3) development of tailored enzyme cocktails (MetZyme® SUNO™) that address harsh process-specific conditions and facilitate improved hydrolysis of pretreated biomass to monosaccharides; (4) development of a Clostridial strain able to ferment cellulosic sugars effectively (target butanol yield > 0.25 g/g pure sugar) and having 20% higher butanol tolerance than baseline strain; (5) development of a patent-pending “In situ product recovery process” based on improved pervaporation fluxes obtained during fermentation that allows continuous operation; (6) validation of the technical performance of the individual stages cited above in a pilot facility using wheat straw as feedstock from handling to product recovery in a 100 L bioreactor; (7) testing of properties and performance of butanol as a blend component in both diesel and gasoline fuels and (8) calculation of GHG emissions of biobutanol in a number of different scenarios based on the use of wheat straw and miscanthus as feedstocks and for the provision of heat, electricity and waste water treatment.

Proceedings of the 26th European Biomass Conference and Exhibition, 14-17 May 2018, Copenhagen, Denmark, pp. 984-990