Utilization of natural compounds (chlorophyll and carotene extracts) as an octane-boosting additive in gasoline

Natural materials should be substituted for organometallic and oxygenated compounds in octane-boosting additives for gasoline because of environmental considerations. Chlorophyll and carotene extracts can be used as octane-boosting additives in gasoline. Maceration and adsorption methods are used to extract them. In this work, chlorophyll and carotene extracts were mixed with fatty acid methyl esters (FAMEs) and a solvent (xylene and gasoline) in a particular composition. The extracted pigment was characterized using ultraviolet-visible (UV−Vis) spectrophotometry. Three different additive formulations with chlorophyll/carotene extract ratios of 0 : 1, 3 : 1, and 2 : 3 were investigated. Additive performance tests included measurements of physical properties, octane number, exhaust hydrocarbon (HC) and carbon monoxide (CO) emissions. The results showed that additives with a chlorophyll/carotene extract ratio of 2 : 3, when added to premium-grade gasoline, increased the octane number by 0.3%. The increase of the octane number was further demonstrated by analysis of the HC composition of the gasoline, where the additive with a 2 : 3 ratio resulted in the greatest increase in the olefin content (22.9%), and the emission tests showed that it could reduce HC emissions by 30.9%.