界面润湿性调控驱油剂的制备与性能评价

Preparation and Performance Evaluation of Oil-displacing Agent with Interfacial Wettability Control

为高效剥离吸附在岩石表面的油膜,以油酸、过氧化氢、乙酸、氢氧化钠等为主要原料,经两步反应制备了一种新型界面润湿性调控驱油剂9,10-二羟基硬脂酸钠(SDHS)。通过红外光谱、核磁共振氢谱对产物进行了结构表征,并对其吸附性能、润湿性调控性能、降低界面张力性能以及油膜剥离性能进行了评价。结果表明,SDHS在亲油处理后的云母片表面均匀吸附。SDHS可通过吸附调控亲油岩石表面润湿性至强亲水/水下疏油状态。将亲油处理的玻璃片在0.3%SDHS溶液中浸泡48 h,玻璃片表面的水滴接触角由99.2°降至27.1°,水下油滴接触角由18.1°增至142.3°。SDHS可将油水界面张力降低至1 mN/m以下,0.3%SDHS溶液降低界面张力能力最强。40℃下,经0.3%SDHS处理48 h,载玻片表面的油膜面积减小53.6%,油膜剥离能力优于传统表面活性剂如十二烷基硫酸钠。SDHS同时降低油水界面张力和调控固液界面润湿性,油膜剥离效果较好,有望进一步提高采收率。

In order to peel off the oil film adsorbed on the rock surface efficiently,a novel oil-displacing agent 9,10-dihydroxyl sodium stearate(SDHS)with the capability of interfacial wettability control was synthesized by a two-step method using oleic acid,hydrogen peroxide,acetic acid and sodium hydroxide.The final product was characterized by Fourier transform infrared spectroscopy(FT-IR)and proton nuclear magnetic resonance(1H NMR),and their adsorption property,wettability control property,interfacial tension reduction property,and oil film peeling performance were evaluated.The results showed that SDHS was evenly absorbed onto the surface of lipophilic-treated mica sheet.When lipophilic-treated glass sheet was immersed in 0.3%SDHS solution for 48 hours,the water contact angle in air reduced from 99.2°to 27.1°,while the underwater oil contact angle increased from 18.1°to 142.3°,indicating that SDHS could regulate the surface wettability of oil-wet rock to a strong hydrophilic and under water oil-repellent state by adsorption.SDHS could reduce the oil-water interfacial tension below 1 mN/m,and 0.3%SDHS solution exhibited the best performance in reducing the interfacial tension.At 40℃,0.3%SDHS solution could reduce the area of oil film by 53.6%after soaking glass slide within 48 hours,whose oil film peeling performance was better than that of traditional surfactant such as sodium dodecyl sulfate(SDS).SDHS could simultaneously reduce the oil-water interfacial tension and regulate the wettability of solid-liquid interface,and exhibited excellent oil film peeling performance,which could be applied for further improving the oil recovery.