During the first reporting period, the experimental work has been carried out using mainly laboratory scale reaction systems in terms of the feedstock pre-treatment and enzymatic hydrolysis to cellulosic sugars, the fermentation of cellulosic sugars to MVL over engineered microbes and the thermo-catalytic conversion of MVL to isoprene and 3MPD over inexpensive heterogeneous catalysts. The main focus has been to develop and optimize the process conditions, reactor configurations and microbes/heterogeneous catalysts for the aforementioned process steps. At the same period, based on the experimental results, first conceptual designs of the proposed process with techno-economic and environmental evaluation have been achieved. The work that has been performed during M1-M18 allowed the selection of the optimum conditions for the demonstration of the process at larger scale that will be performed in the second half of the project.
The feedstock evaluation study led to the selection of five different low quality residual lignocellulosic biomasses with high potential and the efficient pre-treatment and production of 10 kg of pre-treated material from wheat straw, birch chips and spruce sawdust. Enzymatic hydrolysis experiments were performed on 100 lt scale with the selected biomasses and produced a total quantity of 8.5 kg of cellulosic sugars.
An improved strain with MVL-producing genes on a plasmid that uses nadC instead of kanR as a marker, for plasmid maintenance and for production of MVL was successfully engineered. Different hydrolysates produced from the selected biomasses were evaluated to determine the optimized conditions and feedstock for MVL production. Fermentation was scaled-up to 2 lt, producing 50 g/lt of MVL starting from birch hydrolysate.
The efficient thermochemical conversion of sugar-derived mevalonolactone to 3-methyl-1,5-pentanediol over inexpensive Cu-based catalysts with > 80 % yield was demonstrated on lab-scale. For the MVL to isoprene route, more than six new catalysts were tested, achieving a maximum yield of ~ 60% (based on theoretical maximum). These values are close to the targets set in the proposal and it is considered feasible to achieve them after optimization of the process conditions and reactor configuration that will be performed in the second half of the project.
The first design of the process for the production of 3-methyl 1,5-pentanediol from second generation sugars was completed and the risks linked with the financing needs, the supply chain, the establishment of a first production unit were identified.
Regarding dissemination, the 1st technical workshop was successfully organized on May 15, 2019, in Delft, Netherlands. In December 2018 the first Annual Newsletter of the project was published. The BioCatPolymers project and its innovative technology were presented at four well renowned conferences and a workshop.
