PiCK – Plasma-induced CO2 conversion

The Kopernikus satellite project PiCK is developing a novel process employing implementing regenerative electrical energy to utilize climate-damaging CO2 as a carbon source. A combination of plasma and membrane processes  will be used to break down CO2 into O2 and CO, which serves as the starting product for the synthesis of platform chemicals and chemical energy stores such as methanol. Within the framework of the project, gas-tight ceramic capillaries were produced at IGB for the first time. These capillaries are both CO2-stable and suitable for the separation of oxygen from a plasma.

© IGVP /Fraunhofer IGB
Fig. 1: Schematic representation of the PiCK project.

The aim of this development is to make CO2 usable as a chemical raw material and for the chemical storage of energy, thus contributing to the climate targets aimed at. Using a cost-efficient and resource-saving combination of plasma and membrane processes, CO2 is split into O2 and CO, which can serve as a starting product for the synthesis of platform chemicals such as methanol (Fig. 1). The membrane process is needed to prevent the recombination of CO and O2 to CO2.

© Fraunhofer IGB
Fig. 2: Light microscopic images of gas-tight LCCF capillaries.

The focus of the work at IGB is on the development of a suitable membrane, which on the one hand efficiently separates oxygen and on the other can be used in the plasma. A mixed conductive ceramic material (LawCaxCoyFezO3-δ; LCCF), which has already been described in the literature as CO2-tolerant, was selected for the manufacturing of the membranes. Using an established wet-spinning process and subsequent sintering, for the first time gas-tight LCCF capillaries (Fig. 2) were produced in a reproducible manner that are both CO2-stable (>200 h) and suitable for the separation of oxygen (O2 permeance of 1.0 ml min-1 cm-2 at 900°C).

© IGVP
Fig. 3: LCCF capillary in CO2 plasma.

The capillaries produced by Fraunhofer IGB were investigated at IGVP in a CO2 plasma (Fig. 3).

© Fraunhofer IGB
Fig. 4: Results of permeation measurement.

They show very good thermal stability and good oxygen permeability in the plasma (2.3 ml min-1 cm-2 at 1 kW; see Fig. 4). Such capillaries have not yet been described in the literature. The next step is to optimize the separation efficiency by increasing the membrane area in the plasma. This is done by increasing the number of hollow fiber membranes built into the plasma.

Project information

Project title

PiCK – Plasma-induced CO2 conversion

 

Project duration

February 2017 – February 2020

 

Project partners

  • University of Stuttgart, Institute of Interfacial Process Engineering and Plasma Technology IGVP, Dr.-Ing. Andreas Schulz (Coordination)
  • MUEGGE GmbH, Reichelsheim
  • University of Stuttgart, Institute for Materials Science

 

Funding

We would like to thank the German Federal Ministry of Education and Research (BMBF) and the project sponsor Jülich (PTJ) for funding the project "PiCK", promotional reference n° 03FSK2S3D.

Federal Ministry of Education and Research.