Synthesis And Performance Of Cardanol-based Surfactant For Oil Displacement

With the application of alkali-surfactant-polymer?ASP?oil recovery technology in China oil fields,sulfonate surfactant with the largest output and the most widely used oil displacement,has a broad market prospect.Petroleum sulfonate and heavy alkyl benzene sulfonate was the main surfactant for oil displacement.However,their raw materials are non-renewable resources with low purity and relatively high price.So the development of a new type of surfactant with environmental protection,cheap raw materials,easy access and excellent comprehensive performance has always been an important subject in the field of oilfield development of China National Petroleum Corporation,and also one of the key problems to be solved in the field of oil recovery technology.As a kind of cheap and renewable biomass resource,cardanol has a wide range of sources and a low price.The structure of cardanol contains both long chain lipophilic group and active phenol hydroxyl group,which can replace petroleum phenol to design and synthesize high efficiency and low cost bio-based surfactant for oil-displacement.Based on the above research focus,a series of cashew phenol-based oil displacement surfactant was synthesized using industrial-grade natural cardanol as raw material in the paper.And the solution properties and oil displacement performance of the cardanol-based surfactants were systematically studied.The main research contents and results are as follows:?1?Series of cardanol-based surfactants were synthesized by etherification,amination and quaternization using biomass cardanol as material,and their structures were confirmed by IR and¹H-NMR.The results of condition optimization for quaternary ammoniation reaction showed that the reaction temperature is 85?,the ratio of n_{sodium 3-chloro-2-hydroxypropane sulfonate}odium 3-chloro-2-hydroxypropane sulfonate and n_{cardanol tertiary amine}ardanol tertiary amine is 3:1,the solvent is the mixture of isopropanol and water,and the ratio of V_isopropanolsopropanol and V_waterater is 2:1.Under the conditions,the yields of series cardanol-based surfactants were above 80%.?2?The surface tension of series of cardanol-based surfactants was measured by the wilhelmy method,the surface activity parameters were calculated,and the relationship between structure and surface tension was studied.The results showed that series of cardanol-based surfactants had good surface activity,and the cmc value was about 10^-4mol/L and?_cmcmc was at the range of 30-32mn/m.With increasing of the length of the alkyl chain connected the quaternary ammonium ions,the surface tension of aqueous solution decreases?G_micincreases and?G_adsds reduced.And the A_minin of the CNBS-Cn-S with SO^3-is larger than that of the CNBS-Cn-C with COO^-.?3?The oil-water interfacial tension of cardanol-based surfactants in the different systems was measured by the spinning drop method.The results showed that the interfacial tension of the single surfactant system decreased with the increase of surfactant concentration,and when the concentration of CNBS-C1-S was 4.00g/L,the interfacial tension was3.66×10^-4mN·m^-1.When the surfactant concentration was 0.23wt%,the emulsion was the most stable for the surfactant system.When the alkali concentration was 1.50wt%and the surfactant concentration was 3.00g/L,the interfacial tension was 1.15×10^-3mN·m^-1for the alkli-surfactant system,and the emulsion is most stable when the surfactant concentration is0.23wt%and the alkali concentration is 1.49wt%.When the surfactant concentration was3.00g/L,the alkali concentration was 1.50wt%,and the polymer concentration was 300mg/L,the interfacial tension reached the lowest and was 2.34×10^-3mN·m^-1for the alkli-surfactant-polymer system.When the surfactant concentration was 3.00g/L,the alkali concentration was 1.50wt%,the polymer concentration increases to 900 mg/L,the emulsion is most stable.?4?The adsorption properties of the cardanol-based surfactants on oil sands were measured by the spectrophotometric method.The results showed that the saturated adsorption capacity increased first and then unchanged with increasing of the surfactant concentration,.The salt and alkali in the system had little effect on the saturated adsorption capacity of cardanol-based surfactants in oil sands.With the increase of alcohol,the saturated adsorption capacity of cardanol-based surfactants decreased.The flooding performance was measured by flooding experiments.The results showed that the oil recovery could be improved for 14.67%for the single surfactant flooding system at the surfactants concentration of 0.30wt%.For the surfactant-alkali flooding system,when the surfactants concentration was 0.30wt%and the alkali concentration was 1.20wt%,the oil recovery was improved for 25.28%.For the surfactant-polymer flooding system,when the concentration of cardanol-based surfactants was 0.30wt%and the polyacrylamide?2500 million?concentration is 800mg/L,the oil recovery was improved for 24.22%.For the surfactant-alkali-polymer flooding system,when the concentration of cardanol-based surfactants is 0.30wt%,the alkali concentration is1.50wt%,and the polyacrylamide?2500 million?concentration is 800mg/L,the recovery rate of subsequent chemical flooding is 33.87%?...