Electrochemical Production of Sustainable Hydrocarbon Fuels from CO₂ Co-electrolysis in Eutectic Molten Melts

Abstract

Due to the heavy reliance of people on the limited fossil fuel as energy resources, global warming has increased to severe levels due to huge CO2 emission into the atmosphere. To mitigate this situation, a green method is presented here for the conversion of CO2/H2O into sustainable hydrocarbon fuels via electrolysis in eutectic molten salts ((KCl-LiCl; 41:59 mol%), (LiOH-NaOH; 27:73 mol%), (KOH-NaOH; 50:50 mol%), (Li2CO3-Na2CO3-K2CO3; 43.5:31.5:25 mol%)) at the conditions of 1.5-2 V and 225-475 o C depending upon molten electrolyte used. Gas chromatography (GC) and GC-MS techniques were employed to analyse the content of gaseous products. The electrolysis results in hydrocarbon production with maximum 59.30, 87.70 and 99% faraday efficiency in case of molten chloride, molten hydroxide and molten carbonate electrolytes under the temperature of 375, 275 and 425 o C 2 respectively. The Gas chromatography (GC) with FID and TCD detectors and GC-MS analysis confirmed that the H2 and CH4 were the main products in case of molten chlorides and hydroxides at 2 V applied voltage while longer hydrocarbons (>C1) were obtained only in molten carbonates at 1.5 V. Through this manner, electricity is transformed into chemical energy. The heating values obtained from the produced hydrocarbon fuels are satisfactory for further application. The practice of molten salts could be a promising and encouraging technology for further fundamental investigation for sustainable hydrocarbon fuel formation with more product concentrations due to its fast-electrolytic conversion rate without the use of catalyst.

Sustainable Conversion of Carbon Dioxide into Diverse Hydrocarbon Fuels via Molten Salt Electrolysis

“…6 revealed that the products in the case of titanium cathodic materials were more specific as found in higher molecular weight, long-chain hydrocarbons and thus offer a higher enthalpy of combustion to produce energy or higher heat values. These findings correlate with the literature 9 .…”

“…..The electrolysis is considered an effective method for the production of hydrocarbon fuel from CO2 and H2O. The aqueous electrolysis at low temperatures (<100 o C) was employed by scientists 9 , whereas suitable catalyst to reduce energy consumption and increase product selectivity is necessary 10 . Besides the low solubility of CO2 in the medium, slow kinetics, low productivity due to unseparated products limits its future use 11 .…”

The impact of COVID-19 lockdown on atmospheric CO2 in Xi'an, China

“…CO 2 emissions must be curtailed to mitigate global warming and enhance sustainable development ( Lelieveld et al, 2019 ). This strategy hinges on alternative energy technologies, which include: solar and wind power ( Qazi et al, 2019 ); sustainable hydrocarbon fuel production from CO 2 ( Al-Juboori et al, 2020b ); hydrogen fuel cells ( Al-Shara et al, 2019 ); and biofuels ( Razzaq et al, 2020 ). Additionally, carbon capture and sequestration techniques such as post-combustion CO 2 capture using fast adsorbents derived from biomass ( Sher et al, 2020 ) can reduce CO 2 emissions.…”

Air Pollutant Emission Abatement of the Fossil-Fuel Power Plants by Multiple Control Strategies in Taiwan

“…In addition, CO 2 and climate change are important issues for power plants. Some new concepts have been introduced: selective configuration of exhaust gas recirculation systems to reduce CO 2 emission in the natural gas combined-cycle power plants [28], and CO 2 capture and reduction via different methods [29,30].…”