Chemical Separation, Purification and Identification of EOR-Active Compounds in Water Soluble Petroleum Sulfonates. Final Progress Report

摘要

There were two major objectives to this contract: (1) being the continuation of the structural characterization of EOR-active fractions from petroleum sulfonate and (2) being the investigation of factors which need not necessarily be structural but still has a bearing on tertiary oil recovery. The two objectives were distributed over four tasks. The first task was a continuation of our earlier effort involving the fractionation and chemical characterization of petroleum sulfonates. Some modifications were made to facilitate handling larger amounts of material at every fractionation step without compromising too much on resolution. As a result of these modifications we could process up to 70 g of ether-extractables from acidic aqueous solution of Pyronate-40 through the Florisil column in one batch and up to 40 g of the EOR-active fraction from the Florisil column could be fractionated through the ODS-silica column operating under the ''Flash Chromatographic'' mode. The preparative HPLC fractions were EOR-active, but the increase in EOR-activity was not commensurate with the increase expected from the enrichment of a few compounds that might be responsible for EOR-activity. The second task was to explore the results observed earlier at METC of increased EOR-activity on remethylation of petroleum sulfonates with diazomethane. Alternate methods of methylation which would eliminate the side products of diazomethane and thereby allow comparison of the esters in structure and EOR-activity with the esters from diazomethane treatment was performed under Task III. The reaction of the sulfonate, either in the acid form or as slat, with PCl sub 5 in benzene followed by reaction with methanol proved to be an alternate method to diazomethane treatment. Under Task IV a spectrophotometric assay for sulfonate in the 2% brine solution was developed and applied to the different pyronate-40 fractions for determining their sulfonate content. 15 refs., 38 figs., 16 tabs. (ERA citation 10:026765)