Decarbonized automotive fuel: Liquefied petroleum gas biosynthesis, benefits and drawbacks

Decarbonization for climate protection through bio-LPG production and application is fast gaining attention in the automotive sector because of its numerous benefits. Despite being a promising green alternative to conventional LPG which reduces carbon footprint by 80%, notable challenges associated with the commercialization of some production processes have hindered its potential global application. While bio-refining is already established as the highest technique for commercial LPG production, the addition of microbial techniques among other routes, using either natural or engineered variants has yet to meet the volumetric demand of high-energy sectors. Environmentally, Bio-LPG is considered a means to control ice formation through CO₂ reduction active prevention of sea ice-melting, and control of glaciers and sea level rise by approximately 21.34 m. However, in automotive applications, this study highlights bio-LPG fuel synthesis processes including natural propane biosynthesis. Highlights of its benefits, for example, in fuel cells and engine oil lubricity, indicate the prospects, and the limitations, such as wall wetting, icing formation, bubble formation associated risks and lower lean misfire can be addressed by adopting controlled fuel deposition within combustion chamber or utilizing additives, introducing heating element device to de-freeze, advancing ignition timing and redesign of the combustion chamber, respectively. Up-scale or increased utilization of HD-5 vehicles is recommendable since a gallon of LPG emits 5.68 kg of carbon dioxide (CO2) compared to the 8.89 and 10.18 kg of CO₂ emitted by gasoline and diesel fuels. Bio-LPG is chemically identical and compatible with all LPG products, therefore can be used directly or as blends.