Abstract
Abstract Earlier research by Kamath et al1 has indicated that the ability of certain water-soluble petroleum sulfonates for successfully recovering tertiary oil from water-flooded Berea sandstone cores can be traced to the presence in them of certain specific but yet-unidentified minor components. This paper summarizes the results of a closely integrated interdisciplinary research consisting of physicochemical and EOR-activity studies directed toward isolating the active components from a commercial petroleum sulfonate (Witco's Pyronate-40) and identifying their chemical structure. Following a pre-extraction with n-hexane and isopropyl alcohol, samples of Pyronate-40 in the acid, sodium salt and methyl ester forms were fractionated chromatographically on a silica gel (Florisil) column using gradient elution, initially with 100% acetonitrile and incrementally adding methanol to a final composition of 100% methanol. The EOR-activities of the chromatographic fractions were determined by means of core flood tests using Berea Sandstone core, 1-1/2" diameter × 8" long, and a small slug of the sodium sulfonates in 2% brine at pH ∼10.10 mg samples of the most EOR-active fractions gave an oil recovery of 0.8-1.6 ml which correspond to 4.4 to 2.2 lb respectively of the sulfonate for producing one barrel of tertiary oil. The EOR-active fractions were subjected to further resolutions by means of Flash chromatography using octadecylsilanized (ODS) silica gel column followed by reversed phase High Performance Liquid Chromatography (HPLC). GC/Mass Spectral examination of the EOR-active fraction (which corresponded to 2% of the starting sample of Pyronate-40) has indicated the presence of a number of components amongst which the identifiable ones corresponded structurally to the synthetic alkylaryl sulfonates such as, 5-(4-ethylbenzene-3-sulfonic acid)-dodecane. A critical discussion is presented on the chromatogrpahic resolution of such a complex mixture to a point where structural identification of EOR-active fraction could be meaningfully undertaken.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
