Earl L. V. Goetheer

The concept of liquid metal membranes for hydrogen separation, based on gallium or indium, was recently introduced as an alternative to conventional palladium-based membranes. The potential of this class of gas separation materials was mainly attributed to the promise of higher hydrogen diffusivity. The postulated improvements are only beneficial to the flux if diffusion through the membrane is the rate-determining step in the permeation sequence. Whilst this is a valid assumption for hydrogen transport through palladium-based membranes, the relatively low adsorption energy of hydrogen on both liquid metals suggests that other phenomena may be relevant. In the current study, a microkinetic modeling approach is used to enable simulations based on a five-step permeation mechanism. The calculation results show that for the liquid metal membranes, the flux is limited by the dissociative adsorption over a large temperature range, and that the membrane flux is expected to be orders of magnitude lower compared to the membrane flux through pure palladium membranes. Even when accounting for the lower cost of the liquid metals compared to palladium, the latter still outperforms both gallium and indium in all realistic scenarios, in part due to the practical difficulties associated with making liquid metal thin films.

This chapter presents discussion of four selected case studies for sustainable carbon capture. The first case study is a high-level techno-economic integration study for CO₂ capture in the waste to energy (WtE) sector, which may result in negative emissions, as a large part of the CO₂ is biogenic. Integration of CO₂ capture in this sector is essential when the need for district heating is low and/or heat is available at a relatively low price. The second case study describes a groundbreaking techno-economic integration study for CO₂ capture on board ships, also called ship-based carbon capture (SBCC). The study considers the operational profile of the ship and uses the available heat integration options to minimize the costs of the process. The third case study entails the techno-economic evaluation of integrating carbon dioxide capture with a biogas facility for biogas upgrading to biomethane. The integrated cycle offers carbon-neutral energy with the potential for negative emissions by storing carbon dioxide underground. The final case study is related to the carbon capture applications in the cement and iron/steel sector. This Page is compulsory Book Title – Sustainable Carbon Capture: Technologies and Applications Chapter Author(s) Jasper A. Ros, TNO, The Netherlands, [email protected] Juliana G.M-S. Monteiro, TNO, The Netherlands, [email protected] Earl L.V. Goetheer, TNO, The Netherlands, [email protected] Randi Neerup, Center for Energy Resources Engineering (CERE), Department of Chemical and Biochemical Engineering, Technical University of Denmark (DTU), Søltofts Plads 229, 2800, Kgs. Lyngby, Denmark, [email protected] Wentao Gong, Center for Energy Resources Engineering (CERE), Department of Chemical and Biochemical Engineering, Technical University of Denmark (DTU), Søltofts Plads 229, 2800, Kgs. Lyngby, Denmark, [email protected] Sai Hema Bhavya Vinjarapu, Center for Energy Resources Engineering (CERE), Department of Chemical and Biochemical Engineering, Technical University of Denmark (DTU), Søltofts Plads 229, 2800, Kgs. Lyngby, Denmark Jens Kristian Jørsboe, Center for Energy Resources Engineering (CERE), Department of Chemical and Biochemical Engineering, Technical University of Denmark (DTU), Søltofts Plads 229, 2800, Kgs. Lyngby, Denmark Sebastian Nis Bay Villadsen, Center for Energy Resources Engineering (CERE), Department of Chemical and Biochemical Engineering, Technical University of Denmark (DTU), Søltofts Plads 229, 2800, Kgs. Lyngby, Denmark Philip Loldrup Fosbøl, Center for Energy Resources Engineering (CERE), Department of Chemical and Biochemical Engineering, Technical University of Denmark (DTU), Søltofts Plads 229, 2800, Kgs. Lyngby, Denmark, [email protected] Chapter Number and Title – Chapter 11, Special Case Studies in Sustainable Carbon Capture

The electrochemical production of valeric acid from the renewable bio‐based feedstock levulinic acid has the potential to replace the oxo‐process, which uses fossil‐based feedstock 1‐butylene. The electrochemical reduction of the ketone functionality in levulinic acid using lead or mercury cathodes has already been known for over 100 years. However, large‐scale electrochemical production of valeric acid might be limited, owing to the toxicity of these materials. In this study, we identified three additional cathode materials, cadmium, indium, and zinc, which selectively and efficiently produce valeric acid. Of these materials, indium and zinc are considered more benign. More specifically, at indium there is no formation of the side product γ‐valerolactone, thus resulting in the highest selectivity towards valeric acid. For the electrochemical reduction, a reaction mechanism involving the formation of an organometallic compound is proposed. Furthermore, a possible processing strategy is outlined to enable the continuous electrochemical production of valeric acid on a large scale.