Plasma-Catalytic Fischer–Tropsch Synthesis at Very High Pressure

Abstract

This study explored Fischer–Tropsch synthesis (FTS) by combining a non-thermal plasma (NTP), generated by an arc discharge reactor at pressures >> 1 MPa, coupled with a mullite-coated 2 wt%-Co/5 wt%-Al2O3 catalyst. The FTS product yields and electrical energy consumption for the pure plasma (no catalyst) and plasma-catalytic FTS processes were compared under the scope of various reactor operating parameters, namely, pressure (0.5 to 10 MPa), current (250 to 450 mA) and inter-electrode gap (0.5 to 2 mm). The major products, obtained in low concentrations for both processes, were gaseous C1–C3 hydrocarbons, synthesised in the order: methane >> ethane > ethylene > propane. The hydrocarbon product yields were observed to increase, while the specific required energy generally decreased with increasing pressure, decreasing current and increasing inter-electrode gap. Plasma-catalysis improved the FTS performance, with the optimum conditions as: (i) 10 MPa at 10 s and 2 MPa at 60 s for the pressure variation study with the longer treatment time producing higher yields; (ii) 250 mA for the current variation study; (iii) 2 mm for the inter-electrode gap variation study. Plasma-catalysis at a gap of 2 mm yielded the highest concentrations of methane (15,202 ppm), ethane (352 ppm), ethylene (121 ppm) and propane (20 ppm), thereby indicating the inter-electrode gap as the most influential parameter.

Plasma-Catalytic Process of Hydrogen Production from Mixture of Methanol and Water

“…Various plasma-catalytic systems are used. A catalyst may be located in a plasma zone [1][2][3][4][5][6][7], an electrode may be the catalyst [8,9], and often the catalyst is located outside the plasma zone [1,[10][11][12][13][14][15][16][17][18]. This way of placing the catalyst prevents the destruction of the catalyst by plasma and the disturbance of the discharge.…”

“…As a result of introducing the catalyst into the plasma reactor, the conversion increases, which results in a reduction of the energy cost of the process. Processes such as gas purification [1][2][3], hydrogen production [5,7], Fischer-Tropsch synthesis [6] are carried out in plasma-catalytic reactors.…”

Electrification of gasification-based biomass-to-X processes – a critical review and in-depth assessment

“…The formation of C 1 to C 3 species increases with pressure when converting syngas via non-thermal plasma-catalysis. 305,[309][310][311]…”

An Overview on Dynamic Phase Transformation and Surface Reconstruction of Iron Catalysts for Catalytic Hydrogenation of COx for Hydrocarbons

“…Despite the advancements over the past decades, plasma-driven catalysis is mostly used in the environment remediation field (e.g., VOCs decomposition, organic pollutant degradation) or in the chemical reactions between smallmolecules (such as methanation, methanol synthesis, steam reforming and RWGS, etc. ). − Although plasma has been commonly employed as a pretreatment procedure for FTS catalyst synthesis, reports on plasma-driven FTS reactions under high pressure are limited. Characterization studies on plasma-treated Co-based FTS catalysts have revealed notable benefits from direct treatment with H 2 and CO plasma.…”