Process intensification in gas-to-liquid reactions: plasma promoted Fischer-Tropsch synthesis for hydrocarbons at low temperatures and ambient pressure

Abstract

The Fischer-Tropsch synthesis (FTS) for the conversion of carbon monoxide and hydrogen to higher hydrocarbons was investigated over a supported Cu/Co catalyst promoted by dielectric-barrier discharges (DBDs) at relatively low temperatures and ambient pressure. The effect of plasma power, operation pressure, and H 2 /CO molar ratio on the activity and selectivity of the catalyst in a DBD reactor were studied. The fresh and used catalyst samples were characterized by scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray, and X-ray diffraction. We also used DBDs in catalyst preparation as a technique to enhance metal distribution on the catalyst support. The present study reveals that plasma can promote the FTS over a Cu/Co-based catalyst at low temperatures and ambient pressure. The formation of methane was strongly suppressed in plasma. In contrast to conventional FTS, CO conversion was higher at low operating pressure than that at higher pressure in the DBD-promoted FTS, which indicates the presence of a new reaction path for FTS.

Co-Assembled Supported Catalysts: Synthesis of Nano-Structured Supported Catalysts with Hierarchic Pores through Combined Flow and Radiation Induced Co-Assembled Nano-Reactors

“…When Co 3 O 4 reduction was carried out at 550˝C in H 2 , metallic cobalt with some CoO (without any Co 3 O 4 ) were obtained indicating that the initial Co 2 O 3 was first reduced to CoO followed by Co. Following a prolonged plasma promoted Fischer-Tropsch synthesis [47] for 150 h, Co/Si catalyst was removed and XRD pattern was obtained which indicates oxidation of Co to CoO [8]. However, the catalyst can be reduced in-situ using the same plasma-reactor system which was used in the Fischer-Tropsch synthesis [8].…”

“…The type of catalyst developed here is also suitable as a high temperature heterogeneous catalyst and has been used in gas-to-liquid conversion processes [45][46][47] including dry reforming [45], ammonia synthesis [46] and Fischer-Tropsch synthesis [47]. However, high temperature catalyst oxide reduction or high temperature catalytic processes result in the enlargement of the catalyst size.…”

“…Therefore, the catalyst oxide size after thermal treatment at high temperature will be a more realistic characteristic of the catalysts. Nevertheless, it is also possible to use these catalysts successfully for low temperature gas-to-liquid conversion processes using non-thermal plasma when the catalyst reduction is carried out in-situ at low temperatures, <250˝C [8,[45][46][47].…”

“…The cobalt catalyst was used in Fischer-Tropsch synthesis [47] and the nickel catalyst was used in ammonia synthesis [46] and dry reforming [45]. Reduction was carried out at 550˝C using H 2 at atmospheric pressure.…”

Stereoselective Syntheses of Aza, Amino and Imino Sugar Derivatives by Hydroboration of 3,6‐Dihydro‐2H‐1,2‐oxazines as Key Reaction

“…These 1,2-oxazines exhibit three characteristic reactive sites (Scheme 1): first, the N-O bond, which is susceptible to reductive ring opening processes leading to acyclic 1,3-and 1,4-amino alcohols as precursors for azetidine [2] or pyrrolidine derivatives; [3] second, the O-substituted side chain at C-3 proved to be essential in (Lewis) acid mediated interactions with the enol ether moiety furnishing a variety of heterocyclic skeletons, e.g. furans, [4] pyrans, [5] oxepanes; [6] finally, the double bond can also be exploited by reaction with external reagents for cyclopropanation [7] or bromination. [8] The stereochemical outcome of these processes is strongly influenced by the configuration of the existing stereogenic centre at C-3.…”