Oxidative Functionalization of Long-Chain Liquid Alkanes by Pulsed Plasma Discharges at Atmospheric Pressure

Abstract

We introduce the oxidation of long aliphatic alkanes using non-thermal, atmospheric plasma processing as an eco-friendly route for organic synthesis. A pulsed dielectric barrier discharge in He/O2 gas mixtures was employed to functionalize n-octadecane. C18 secondary alcohols and ketones were the main products, with an optimal molar yield of ∼29.2%. Prolonged treatment resulted in the formation of dialcohols, diketones, and higher molecular weight oxygenates. Lighter hydrocarbon products and decarboxylation to CO2 were also observed at longer treatment times and higher power inputs. A maximum energy yield of 5.48 × 10–8 mol/J was achieved at short treatment times and high powers, associated with higher selectivity to primary oxygenates. Direct hydroxylation of alkyl radicals, as well as disproportionation reactions, are proposed as the main pathways to alcohols and ketones. The results hold promise for functionalizing long hydrocarbon molecules at ambient conditions using catalyst-free plasma discharges.

Polyethylene Valorization by Combined Chemical Catalysis with Bioconversion by Plastic-Enriched Microbial Consortia

“…The microbial consortia used here performed selective terminal oxidation of linear alkanes. This is in contrast to recently published methods, such as nonthermal plasma functionalization of alkanes, which does not allow for the same selectivity. Alkane hydroxylases also perform subterminal and biterminal oxidation of alkanes. − Enriching additional consortia that perform subterminal or biterminal functionalization of alkanes will allow us to tune the bioconversion step for desired end-products.…”

“…The microbial consortia used here performed selective terminal oxidation of linear alkanes. This is in contrast to recently published methods, such as nonthermal plasma functionalization of alkanes, 93 which does not allow for the same selectivity. Alkane hydroxylases also perform subterminal and biterminal oxidation of alkanes.…”

Polyethylene valorization by combined chemical catalysis with bioconversion by plastic-enriched microbial consortia

“…The microbial consortia used here performed selective terminal oxidation of linear alkanes. This is in contrast to recently published methods, such as non-thermal plasma functionalization of alkanes 87 , which does not allow for the same selectivity. Alkane hydroxylases also perform sub-terminal and bi-terminal oxidation of alkanes [51][52][53][54] .…”

Plasma Electrochemistry for Carbon–Carbon Bond Formation via Pinacol Coupling

“…10 Several new strategies have been reported for generating solvated electrons such as sonolysis, 11 photodetachment of the iodide anion, 12 ultraviolet (UV) illumination of hydrogenterminated diamond, 13,14 visible-light illumination of plasmonic metal nanoparticles, 15−17 and two-photon irradiation of photocatalysts. 18,19 However, these techniques are limited by low solvated electron production rates, 25,26 which when applied to chemical synthesis, results in low product yields. 18 In addition, some of these techniques still rely on costly or scarce materials that may be an impediment to scale up.…”