Chemical processing using non-thermal discharge plasma
A method for activating chemical reactions using a non-thermal capillary discharge plasma (NT-CDP) unit or a non-thermal slot discharge plasma (NT-SDP) unit (collectively referred to as “NT-CDP/SDP”). The NT-CDP/SDP unit includes a first electrode disposed between two dielectric layers, wherein the first electrode and dielectric layers having at least one opening (e.g., capillary or a slot) defined therethrough. A dielectric sleeve inserted into the opening, and at least one second electrode (e.g., in the shape of a pin, ring, metal wire, or tapered metal blade) is disposed in fluid communication with an associated opening. A non-thermal plasma discharge is emitted from the opening when a voltage differential is applied between the first and second electrodes. Chemical feedstock to be treated is then exposed to the non-thermal plasma. This processing is suited for the following exemplary chemical reactions as (i) partial oxidation of hydrocarbon feedstock to produce functionalized organic compounds; (ii) chemical stabilization of a polymer fiber (e.g., PAN fiber precursor in carbon fiber production; (iii) pre-reforming of higher chain length petroleum hydrocarbons to generate a feedstock suitable for reforming; (iv) natural gas reforming in a chemically reducing atmosphere (e.g., ammonia or urea) to produce carbon monoxide and Hydrogen gas; or (v) plasma enhanced water gas shifting.
1. A method for activating chemical reactions using a non-thermal discharge unit that includes a first electrode disposed between two dielectric layers, the first electrode and dielectric layers having at least one opening defined therethrough, and at least one second electrode disposed in fluid communication with an associated opening, the method comprising the steps of:
generating a non-thermal plasma discharge from the opening by applying a voltage differential between the first and second electrodes; and
exposing a chemical feedstock to the non-thermal plasma emitted from the opening.
2. The method in accordance with claim 1 , wherein the opening is a capillary and the unit further comprises a dielectric sleeve inserted in the capillary.
3. The method in accordance with claim 2 , wherein the opening is defined radially outward through the first electrode and dielectric layers.
4. The method in accordance with claim 2 , wherein the second electrode is a metal pin or ring.
5. The method in accordance with claim 1 , wherein the opening is a slot.
6. The method in accordance with claim 5 , wherein the opening is arranged in a longitudinal direction, a spiral direction, or a direction substantially perpendicular to the longitudinal axis.
7. The method in accordance with claim 5 , wherein the second electrode is a metal wire or tapered metal blade.
8. The method in accordance with claim 1 , further comprising a voltage bus connecting the second electrodes to a voltage source.
9. The method in accordance with claim 8 , wherein the voltage bus is one of a wire mesh or a metallic sheath.
10. The method in accordance with claim 1 , wherein the chemical reaction is partial oxidation of hydrocarbon feedstock to produce functionalized organic compounds.
11. The method in accordance with claim 1 , wherein the chemical reaction is chemical stabilization of a polymer fiber.
12. The method in accordance with claim 11 , wherein the polymer fiber is a polyacrylonitrile precursor used in carbon fiber production.
13. The method in accordance with claim 1 , wherein the chemical reaction is pre-reforming of higher chain length petroleum hydrocarbons to generate a feedstock suitable for reforming.
14. The method in accordance with claim 1 , wherein the chemical reaction is natural gas reforming in a chemically reducing atmosphere to produce carbon monoxide and Hydrogen gas.
15. The method in accordance with claim 14 , wherein the chemically reducing atmosphere is ammonia or urea.
16. The method in accordance with claim 1 , wherein the chemical reaction is plasma enhanced water gas shifting.