Dielectric Barrier Coaxial Reactor
Product Detail
The dielectric barrier coaxial reactor is a tubular cold-plasma reactor: two concentric electrodes separated by a dielectric barrier, with the process gas flowing through the annular discharge gap between them. The coaxial geometry produces a uniform dielectric barrier discharge along the full length of the tube, which makes it ideal for continuous, flow-through gas-phase plasma chemistry. ACS Material custom-designs and fabricates single-dielectric, double-dielectric, and heatable coaxial reactors tailored to each customer's gas, throughput, and reaction — we design, we test, and we deliver.
How a coaxial DBD reactor works
A coaxial reactor places a rod or tube electrode at the center of an outer cylindrical electrode, with a dielectric barrier (quartz, alumina ceramic, or glass) covering one or both electrodes. The process gas flows through the ring-shaped gap between them. When a CTP-series supply drives the voltage across the gap past its breakdown threshold, a dielectric barrier discharge fills the annulus — and because the dielectric limits how much charge can cross, the gas breaks into many short-lived micro-discharge filaments that stay cold rather than collapsing into a hot arc.
Two features set the coaxial geometry apart from a flat parallel-plate cell such as the DBD-50:
- Flow-through processing — gas passes continuously along the tube, so the reactor treats a moving stream rather than a fixed sample. Throughput scales simply with tube length and gas flow.
- Uniform, enclosed discharge — the discharge wraps around the full circumference of the inner electrode, giving even treatment, and the closed tube contains the working gas under a chosen atmosphere or pressure.
- Packed-bed ready — the annular gap can be filled with catalyst pellets so the plasma and catalyst act together, the basis of plasma-catalysis.
Configurations we build
Every coaxial reactor is made to order. The three most common configurations are:
| Configuration | Dielectric barrier | Best suited to |
|---|---|---|
| Single-dielectric coaxial | One electrode insulated | General gas-phase DBD chemistry; the most cost-effective option |
| Double-dielectric coaxial | Both electrodes insulated | Corrosive or reactive gases and long, stable runs with no metal–plasma contact |
| Heatable coaxial | Single or double, with integrated heating | Plasma-catalysis and reactions that need elevated temperature |
- Tube diameter and length, electrode and dielectric materials, gas ports, flange and mounting style, viewport, packed-bed support, and heating are all specified to your application.
- All coaxial reactors are passive: each is driven by a separately purchased CTP-series plasma power supply.
Applications
Flow-through cold plasma in a coaxial reactor drives gas-phase chemistry and surface activation at near-ambient temperature, which suits it to:
- Ozone generation from oxygen or air — the classic coaxial DBD application.
- Exhaust-gas and VOC abatement — breaking down volatile organics and odors in a flowing stream.
- CO2 conversion and dry (CO2) reforming of methane — plasma-driven activation of stable molecules.
- Plasma catalysis — a catalyst-packed annular bed where plasma and catalyst work together, often with the heatable configuration.
- Gas-phase synthesis and functionalization of molecules and flowing materials.
- Sterilization and decontamination of gas streams.
Custom design & compatible power supplies
Tell us your gas, flow rate, target reaction, and temperature, and our team designs, simulates, fabricates, and tests a coaxial reactor to match — from a single research tube to a scaled, modular assembly. The reactor pairs with the CTP-2000K plasma power supply family (CTP-2000K, /P, /A, KM, KL), sold separately.
The dielectric barrier coaxial reactor is made to order, so it is quoted per project rather than priced off the shelf. Request a quote or contact us with your application, and pair the reactor with a CTP-series power supply to drive the discharge.
Frequently asked questions
How is a coaxial reactor different from the DBD-50 parallel-plate reactor?
The DBD-50 treats a fixed sample between two flat plates; a coaxial reactor treats a gas flowing through the ring-shaped gap between concentric electrodes. Coaxial geometry is built for continuous, flow-through gas-phase processing, while the DBD-50 suits gas–solid surface work on flat samples and powders.
What is the difference between single- and double-dielectric reactors?
A single-dielectric reactor insulates one electrode; a double-dielectric reactor insulates both. Double-dielectric designs keep the plasma off both metal electrodes, which improves stability for long runs and handles corrosive or reactive gases better.
What does the heatable option add?
Integrated heating lets the reactor run at elevated temperature, which is useful for plasma-catalysis and thermally activated gas-phase reactions where heat and plasma work together.
Can the reactor be packed with a catalyst?
Yes. The annular gap can hold catalyst pellets so the discharge forms within the packed bed — the basis of plasma-catalysis for reactions such as CO2 conversion and reforming.
Which power supply do I need?
Coaxial reactors are passive and are driven by a CTP-series plasma power supply (CTP-2000K, /P, /A, KM, or KL), sold separately. We will recommend a match for your reactor and gas.
How do I order a custom reactor?
Send us your gas, flow rate, target reaction, and temperature. We design, simulate, fabricate, and test the reactor to your specification and quote it per project. Request a quote or contact us to start.
Related products & resources
- Learn the fundamentals: What Is Plasma? Cold Plasma, DBD Reactors, Applications & Power Supplies and Dielectric Barrier Discharge (DBD): Reactors, Physics & Power — our complete guides to cold-plasma generation, DBD reactor physics, and choosing a power supply.
- Parallel-plate reactor: the DBD-50 dielectric barrier discharge reactor for gas–solid surface treatment of flat samples and powders.
- Sealed reaction vessels: DBD reaction kettles for gas, gas–liquid, and liquid-phase chemistry.
- Power supplies: the CTP-2000K plasma power supply and the full CTP power-supply family.
- Browse the line: the complete DBD reactor series (reactors, coaxial reactors, and reaction kettles).
This page describes ACS Material custom dielectric barrier coaxial reactors. Reactors are passive and must be driven by a separately purchased CTP-series plasma power supply; they cannot generate plasma on their own. Photographs and diagrams are for reference only; actual configuration, materials, and performance are specified per project and depend on the paired power supply, working gas, flow, and pressure. Because these reactors are custom-built, they are quoted per project and sold as nonrefundable, made-to-order items; each carries a one-year warranty with free remote maintenance support (shipping excluded). Disclaimer: ACS Material LLC believes the information on this page is accurate and current but makes no warranties, express or implied, regarding suitability for any purpose or the accuracy of the information, and will not be responsible for damages resulting from its use.