Results and Progress

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far 

WP1: In this WP we refined the system requirements for producing biofuels and reviewed the lab-scale process components and product targets, the integrated system specification, and the test protocols for the photocatalytic and electrobiocatalytic processes. 

WP2: According to deliverable D1.1 (Review of materials specifications and specification for target outputs) -Point 4 of Section 1- we previously reported, the recently observed fact (M.P. de Lara-Castells, et al. J. Mat. Chem. A 7, 2019, 7489-7500) that Cu5 clusters can induce a huge increase in the optical response of TiO2 extending it into the visible region. This fact greatly simplifies the synthesis of clusters with absorption in the visible, the search for adequate substrates to support the clusters, and the construction of the photocatalyst. In this reporting period, we aimed to optimise and scale up the previously reported electrochemical synthesis of Cu5 clusters (S. Huseyinova et al. J. Phys.Chem.C, 120, 2016, 15902-15908). For this purpose, we have already increased the active surface area of the electrodes, as shown in the figure. We also investigated the deposition procedure (because the interaction of the clusters with the containers induces large inhomogeneities in the clusters which are deposited onto the TiO2 nanoparticles, and a large proportion of the clusters are lost) and the heating treatments needed to achieve the covalent bonding of clusters onto the TiO2. 

WP3: The work performed from the beginning of the project to the end of the reporting period included density functional theory calculations of the size and shape dependence of isolated Cu5, Ag5, and Au5 atomic quantum clusters (AQCs). 

WP4: TUB built a photoreactor with defined geometry for standardised photocatalyst testing. This is facilitating the comparison of the results between the groups of TUB and USC and this is leading to a better cooperation and feedback on the catalyst preparation. USC can measure the activity of the synthesized Copper-5 clusters with standardised conditions (due to the same photoreactor setup provided by TUB) before sending the Copper-5 clusters to TUB for detailed kinetic studies. The first qualitative trials of the Cu5@TiO2 photocatalysts (prepared using the method developed in WP2) using a solar simulator, gave a hydrogen evolution ≈ 5-8 times larger than the TiO2 alone. We will continue the optimisation of the photocatalyst, and the best one will be sent in approx. 1 month to TUB for the quantitative analysis of the efficiencies. 

WP5: Six different microorganisms were selected with the best set of characteristics for the envisaged task of converting H2 and CO2 into fuels (Deliverable 5.1). These organisms are currently being analysed with respect to their physiology and genetic accessibility. In addition, the thermodynamic potential for the formation of different fuels was investigated and a metabolic model is being constructed for predicting targets for engineering. 

WP6: An initial design of the reactor was prepared to improve the mass transfer of gases (hydrogen and carbon dioxide) and the patentability of the new design was explored. Three different reactor configurations were designed and the reactors were built. The first design is currently being operated and the other two are being set up for testing. Interactions were held with the WP5 leader, Wageningen University with regards to the selection of the bacterial strains. A major effort was undertaken during this period on the feasibility study of the Bac-To-Fuel concept with MI_DICE and the Tech2Market report. 

WP7: Initial evaluations were done for the life cycle assessment of the process. A functional unit and the research question were defined. 

WP8: The consortium has created a project website that has been regularly updated and google analytics analysis has shown that it contributes successfully towards improving dialogue within the consortium and with outside stakeholders. Contents for a first and second press release have been agreed among the members of the consortium. A twitter profile has been developed for the project that is distributing contents related to the project and the related technologies and markets. Consortium members participated in several events, workshops and conferences representing Bac-To-Fuel. 

Progress beyond the state of the art, expected results until the end of the project and potential impacts and use (including socio-economic impact and the wider societal implications of the project so far). 

WP1: As we explain in detail in the report, the specifications and requirements for producing biofuels in terms of: 1) cluster production, 2) photocatalytic and electrobiocatalytic processes involved, and 3) the final efficiencies of the integrated system are well beyond the state of the art. 

WP2: According to the results obtained so far, we are close to achieving a novel production method for AQCs, which can be easily scaled up to produce ≈ 1 g/day of clusters. This is around 4 orders of magnitude larger than the current state of the art for the production of naked clusters by wet chemical methods. This will be a major breakthrough in the production of clusters, so we can foresee that in the near future, AQCs will be able to be produced and applied at an industrial scale. Therefore, their important properties can be exploited, not only in the photocatalysis field, but also in other important areas of socio-economic impact, such as therapeutics, catalysis, etc. 

WP3: WP3 has progressed beyond the state of the art with its detailed simulations of the biding energies of oxygen molecules to the target Cu5 AQC. 

WP4: The photoreactor setup delivered by TUB is expected to improve the development of the photocatalyst as it will provide detailed feedback about their performance. It is expected to enhance the activity of the photocatalysts in the water splitting process with sunlight irradiation. Depending on the amount of hydrogen generated by the photocatalyst that has been developed, the optimised catalyst loading and reaction conditions will provide the basis for the design of the hydrogen generation unit within the demonstration unit. 

WP5: In addition to using established CRISPR-Cas9 tools, WP5 will develop new tools for genome editing in selected acetogenic microorganisms (dCas9, Cpf1, multiplexing), with the aim of improving biofuel production. The engineered micro-organisms will be used in electro-biocatalytic reactors (VITO) for the conversion of H2 and CO2 into fuels. 

WP6: Beyond the conventional microbial electrosynthesis system, which relies on the in situ generation of hydrogen at the electrode surface and which is most often limiting for the bacteria, a new approach to provide hydrogen (produced photocatalytically) along with carbon dioxide will be explored in Bac-To-Fuel. This will lead to a new reactor design with an improved gas liquid supply system that targets fuels like ethanol and butanol using bacteria modified with the CRISPER-Cas9 editing system in WP5 by Wageningen University. Initial calculations of the hydrogen required for the final target were also provided to WP4. 

WP7: As stated before, initial evaluations were done for the life cycle assessment of the process. A functional unit and the research question were defined. 

WP8: A fully-fledged feasibility study with a complete market analysis, competitor scenario and a description of the final end users will be developed in association with MI_DICE. This work is carried out by WP8, but all partners are contributing to it in several ways.