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Dimethyl ether (DME) is an important platform chemical and fuel that can be synthesized from CO2 and H2 directly. In particular, sorption-enhanced DME synthesis (SEDMES) is a novel process that uses the in situ removal of H2O with an adsorbent to ensure high conversion efficiency in a single unit operation. The in situ removal of steam has been shown to enhance catalyst lifetime and boost process efficiency. In addition, the hydrogen may be supplied through water electrolysis using renewable energy, making it a promising example of the (indirect) power-to-X technology. Recently, major advances have been made in SEDMES, both experimentally and in terms of modeling and cycle design. The current work presents a techno-economic evaluation of SEDMES using H2 produced by a PEM electrolyzer. A conceptual process design has been made for the conversion of CO2 and green H2 to DME, including the purification section to meet ISO fuel standards. By means of a previously developed dynamic cycle model for the SEDMES reactors, a DME yield per pass of 72.4 % and a carbon selectivity of 84.7% were achieved for the studied process design after optimization of the recycle streams. The production costs for DME by the power-to-X technology SEDMES process at 23 kt/year scale are determined at ∼€1.3 per kg. These costs are higher than the current market price but lower than the cost of conventional DME synthesis from CO2. Factors with the highest impact on the business cases are the electricity and CO2 cost price as well as the CAPEX of the electrolyzer, which is considered an important component for technology development. Furthermore, as the H2 cost constitutes the largest part of the DME production cost, SEDMES is demonstrated to be a powerful technology for efficient conversion of green H2 into DME.

The ability to effectively control and optimize surface modification of metal nanoparticles is paramount to the ability to employ metal nanoparticles as diagnostic and therapeutic agents in biology and medicine. Here we present a high-throughput two-dimensional-grid gel electrophoresis cell (2D-GEC)-based method, capable of optimizing the surface modification of as many as 96 samples of metal nanoparticles in approximately 1 h. The 2D-GEC method determines not only the average zeta-potential of the modified particles but also the homogeneity of the surface modification by measuring the distance between the front of the sample track and the area where the maximum optical density is achieved. The method was tested for optimizing pH and concentration of the modifiers (pM) for functionalizing gold nanorod thiol-containing acidic agents.

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The diffusion permeability through new hybrid materials based on a Nafion-type membrane (MF-4SC) and nanotubes of halloysite is investigated using the Nernst-Planck approach. A method of quantitative evaluation of physicochemical parameters (averaged and individual diffusion coefficients and averaged distribution coefficients of ion pairs in the membrane) of system "electrolyte solution-ion-exchange membrane-water", which was proposed earlier, is further developed. The parameters of hybrid membranes on the base of MF-4SC and nanotubes of halloysite (5% wt and 8% wt) are obtained from experimental data on diffusion permeability of NaCl solutions using theoretical calculations. New model of three-layer membrane system can be used for refining calculated results with taking into account both diffusive layers. It is shown that adding of halloysite nanotubes into the membrane volume noticeably affects exchange capacity as well as structural and transport characteristics of original perfluorinated membranes. Hybrid membranes on the base of MF-4SC and halloysite nanotubes can be used in fuel cells and catalysis.

Dimethyl ether (DME) could have a promising future as a sustainable diesel fuel replacement as it requires only relatively minor engine modifications. It can be produced from renewable H2 and captured CO2 using Power-to-X technologies. To gain support through the EU Renewable Energy Directive, the production and use of CO2-derived DME as a fuel needs to produce emission savings of at least 70% over the petrodiesel alternative. This study assesses the carbon footprint of producing DME via the sorption-enhanced DME synthesis (SEDMES) process and using it as a transport fuel, compared to producing and using fossil-based petrodiesel. The cradle-to-grave (well-to-wheel) carbon footprint of using DME as a transport fuel is found to be 77% lower than for petrodiesel, if offshore wind power is used for H2 synthesis and DME production. If renewable energy is also used for CO2 capture and waste heat is used for the DME production and purification steps, the DME carbon footprint has the potential to be over 90% lower than that of the fossil-fuel comparator.

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