Atmospheric pressure plasmas, unlike low-pressure plasma or high-pressure plasma, do not require a reaction vessel to maintain a pressure level or gas atmospheres different from atmospheric pressure. Such plasmas are used at low current densities to activate surfaces. In addition to the classical states of matter (solid, liquid and gas), plasma is often referred to as the "fourth" state of matter, since it has a different character compared to the classical three states.
By plasma is meant a strongly ionized gas, which is very different from usual gases. In addition to the neutral particles in the plasma (atoms and molecules), there are mobile charge carriers in the form of electrons and ions. These can be charged atoms or charged molecular residues.
Advantages of atmospheric plasma from Fricke and Mallah:
- Only air is required as the process gas, no other gases are needed
- High efficiency due to integrated adaptation elements
- Process reliability due to adapted processes
- Cost-efficient - no further media required for cleaning or activation
- Environmentally friendly and energy efficient
Fields of application:
Plasma Pyrolysis of Methane
In a microwave plasma reactor natural gas is directly converted to pure carbon and hydrogen. This is also the main benefit of the dry methane reforming reaction in a microwave plasma reactor over for example conventional steam methane reforming: no carbon dioxide is formed in the process. While steam methane reforming comes with the disadvantage of carbon dioxide emissions and needs expensive carbon capture and storage technologies, this extra step can be spared with a microwave plasma reactor. Additionally, the pure carbon adds value to the process as an extra revenue, since this chemical is desired for e.g. tire manufacturing, gaskets or simply for shoe soles.
Syngas for synthesizing e.g. methanol
Currently, synthesis gas (syngas) for synthesizing methanol is generated via coal gasification. A microwave plasma reactor is rather flexible to the process gas. It does not necessarily have to be a pure gas, it can also contain a gas mixture, e.g. methane and carbon dioxide (CH4 and CO2). In a plasma reactor this gas mixture is converted to a syngas of carbon monoxide (CO) and hydrogen (H2), potentially also accompanied by the deposition of solid carbon. The syngas can afterwards be used for synthesizing e.g. methanol.
These reactions are examples. The plasma reactor can convert other process gases as well. Contact us to learn more. We are happy to develop your process with you.
Application areas for gas flow reactors
- Production of clean hydrogen as the cornerstone for a successful energy transition and energy carrier of the future
- Decarbonization of industry and society
- Production of synthetic fuels for the energy transition (e.g. power-to-X)
Microwave plasma technology is one of the most efficient processes for surface treatment of plastics, metals, glass, recycled materials or composites. It is used for cleaning, activation or coating of surfaces and is applied in the field of electrical engineering, automotive industry, textile industry and many other industries.
Together with Heuermann HF-Technik GmbH, Fricke und Mallah develops microwave plasma sources with excellent heat coupling (rapid heating). The result is a particularly high plasma density and high temperature processes up to 5000° C. More Details
Microwave generators developed in-house are used as the source. The operating frequency is 2.45 GHz, in the ISM band, and can thus be used worldwide without any further approvals. The microwave generators provide power in the single-digit kW range.
Application areas for surface treatment
Recombination on the surfaces makes the following applications conceivable:
- Treatment of carbon fibers
- Deposition of thin layers
- Activation of surfaces
- Heating of thin layers with underlying critical materials
- Smoothing of porous surfaces
- Surface treatment of foils
- Surfaces of porous filters (sintered)
- Electrode surfaces for batteries/capacitors
- Spot heating of components
- Exhaust gas cleaning
- 3D printing of metals