posted on 2019-11-26, 16:06authored byAdriano Randi
The increasing levels of CO2 in the atmosphere and its consequential impact on global warming is driving many research groups to develop ways to use CO2 as raw material. For example, to produce feedstocks, or fuels.
A wide variety of approaches to carbon dioxide utilisation have been reported employing homogeneous catalysis, heterogeneous catalysis, photocatalysis, photoreduction and electrochemical reduction.
Besides the reduction of greenhouse gases, by producing feedstocks using CO2 will greatly reduce our dependence of fossil fuels for chemical synthesis. Our previously reported electrochemical processes have proven to be successful in terms of electron transfer between substances at room temperature and atmospheric pressure.
Atmospheric-pressure plasmas interacting with organic liquids offer a new possibility for chemical synthesis that remains largely unexplored. Here I reported the results obtained with a Jet device in which chemical reactions are triggered in an organic liquid by an atmospheric-pressure plasma.
As a proof-of-concept, I considered the incorporation of CO2 into an alkyne to form a carboxylic acid. Here I explore plasma reduction. A CO2 saturated solution of trans-stilbene in Lithium Tetrafluoroborate (LiBF4), and Dimethylformamide (DMF). Argon DC plasma is used as a gaseous cathode to provide electrons for the reduction of CO2. Gas chromatography Mass Spectroscopy (GCMS) and Nuclear Magnetic Resonance (NMR) analysis indicate the formation of its corresponding carboxylic acid with good selectivity.