current activities

A new CCU technology

We develop a CCU technology which combines enzymes specified to convert CO2 to methanol with an optimized porous support. The technology does not require H2 gas and can be implemented at any CO2 emitting industry (such as coal fire plants) creating value of an unused residue and lowering green-house emissions.

Enzyme catalysis

Enzyme catalysis supported onto a porous support has a number of advantages to other techniques for CO2 capture and storage and bio-methanol production:
  1. Effective and pure process -The enzymes are 100% specific to each reactant, i.e. no molecules are adsorbed on the enzyme other than CO2. As compared to inorganic catalysis methods an inorganic surface is not specific but can adsorb molecules with identical reactive groups but with a different ”backbone” or basic structure. This may lead to impure products and lower efficiency.

  2. No need of hydrogen gas (hydrogen atoms are obtained from water in the process)- Most fossile-free methods for methanol production require hydrogen gas. If hydrogen is synthesized by electrolysis of water, this is a further step which requires energy and increases complexity and cost of the synthesis. Hydrogen gas can also be obtained from synthesis (syn)gas, but this puts restraints on that the syngas has been produced by a fossile free process.

  3.  Enzyme effective units used instead of full bacterium – Bacterial conversion of carbon dioxide to produce methanol using methylotrophic organisms has gained some interest in the latest years but is less efficient in terms of size and action, as only one of the thousands of enzymes in a bacterium is efficient towards carbon dioxide conversion. It should be noted that this process runs totally backwards, compared to the normal process in the methylotrophs, and does thus require a great energy input to the bacteria. Product inhibition of methylotrophs due to high methanol production, maintenance of physiological activity, catalytic activity and viability of microbes in addition to the toxicity of feedstock is another major challenge towards industrial implementation of the technology In addition to issues pertaining to the growth medium and the ultimate fate of deceased archaea cells, the low solubility of H2 in water and the slow transport of H2 and CO2 into water are key limitations of methanol synthesis from full bacterium.

  4. Enhanced stability compared to regular enzyme catalysis without inorganic support – The enzyme stability can be greatly improved compared to that of enzymes in solution when mounted onto a porous support. The mobilized enzymes can potentially be exchanged automatically, reducing the need of new porous support.

  5. No large land requirement needed – Renewable Bio-methanol production from biomass is a promising route to low carbon synthesis of methanol, although land requirements are large. Our synthesis method offers good cost control and is not limited by the availability of biomass (enzyme production is scalable without large land requirements).

  6. No elevated pressure, temperature, dangerous chemicals or precious metals used – Our process is performed at ambient conditions, using a water based substrate solution and no precious metal catalysts. Precious metals are expensive, difficult to recover and discourage industrial exploration.

  7. Day reactor for energy storage – The reactor can be used for daily energy storage in case of methanol overproduction. It can then run in opposite direction (methanol-CO2) to obtain electricity from the oxidation process in a day reactor.

A circular process

We implement local bioprocessing of enzymes, carefully select materials and optimize the process to minimize carbon footprint of the entire development process. We utilize advanced computational modelling to minimize experiments and chemical waste in collaboration with Luleå University of Technology, IIT Ropar, Punjab and Harish-Chandra Research Institute (HRI) Allahabad, India.

Spatial Configuration of the pore inside chain A of Alcohol oxidase from Phanerochaete chrysosporium (PcAOX) (PDB ID: 6h3g) (accredited to Vahid Fadei Naeini, Luleå University of Technology)

Bioprocessing of enzymes

We implement local bioprocessing of enzymes, carefully select materials and optimize the process to minimize carbon footprint of the entire development process. We utilize advanced computational modelling to minimize experiments and chemical waste in collaboration with Luleå University of Technology, IIT Ropar, Punjab and Harish-Chandra Research Institute (HRI) Allahabad, India.

Schematic illustrating adapted from Bernadette Byrne et al.1 showing the key steps in expression of an integral membrane protein in the methylotrophic yeast, P. pastoris. E. coli is typically used for construct generation and amplification (a). Following confirmation of the correct sequence (b), the expression vector containing the gene of interest together with appropriate tags and protease cleavage sites is transformed into electrocompetent P. pastoris cells (c). The DNA is linearised before transformation and so integrates into the host vector. In our laboratory all our research involved the SMD1163 protease deficient strain. Depending on the expression vector and cell line combination used initial selection of the colonies can be done using antibiotics (e.g.zeocin) or (d) auxotrophy of the strains. Colonies initially selected using cell auxotrophy can then be further selected based on vector copy number using increasing concentrations of the antibiotic G418 or zeocin (e). Although this indicates copy number it is not necessarily indicative of the expression level of the target protein. Small scale expression trials can be carried out in 10–50 mL culture volume (f). Expression levels of the target protein can be assessed using (g) functional analysis, Western blot analysis or direct fluorescence measurements where GFP is used as a tag. Once the best expressing clone is identified this can be used for large scale expression either in shaker flasks or bioreactors (h).

1Bernadette Byrne, Pichia pastoris as an expression host for membrane protein structural biology; Current Opinion in Structural Biology 2015, 32:9–17.