Synthesis and Characterization of Green Surfactants from Selected Underutilized Local Plant Seeds: A Sustainable Alternative for Oilfield Applications

Abstract

This research looks into the potential of green surfactants made from underutilized local plant seeds. Delonix regia, Jatropha curcas, and Hura crepitans plants are recognised for their high oil content, with seeds containing as much as 150-200 (mg KOH/g fat) saponification. These plants are a prospective resource for surfactant manufacturing since they are sustainable, environmentally friendly, and economically viable, particularly in areas where they are widely farmed. The study focusses on the synthesis of green surfactants using the esterification, transesterification, and sulfonation processes. Gas chromatography mass spectroscopy (GMCM) and Fourier transform infrared spectroscopy (FTIR) were utilised to validate the synthesis method and compare the results to highly sought-after commercial surfactants. GCMS analyses revealed the presence of medium to long chain fatty acid methyl esters, while DR-MES revealed the presence of Octanoic acid, methyl ester; Decanoic acid, methyl ester; Dodecanoic acid, methyl ester; Hexadecanoic acid, methyl ester; Eicosanoic acid, methyl ester; Heneicosanoic acid, methyl ester; Docasanoic acid, methyl ester; Tricosanoic acid, methyl ester. JC-MES contains methyl esters of octanoic acid, nonanoic acid, and hexadecanoic acid. 9-Octadecynoic acid, methyl ester; Eicosanoic acid, methyl ester; Docosanoic acid, methyl ester; HC-MES reveals the presence of Dodecanoic acid, methyl ester; Hexadecanoic acid, methyl ester; Octadecadienoic acid, methyl ester; Nonadecenoic acid, methyl ester; Octadecatrienoic acid, methyl ester; Eicosanoic acid, methyl ester; Docosanoic acid, methyl ester. Along with verified functional groups, the presence of these fatty acid methyl esters with medium chain carbon compounds (C10–C18) is a clear sign of the presence of surface-active components that have a great ability to lower surface tension, form micelles, and enhance the surfactants’ overall biodegradability.