新型两性Gemini表面活性剂制备及表界面性能

Preparation and surface performance of new amphoteric Gemini surfactants

关键词:  两性Gemini表面活性剂  表界面活性  耐温抗盐性  岩心驱替实验

Key words:  sulfate-quaternary ammonium Gemini surfactant  surface activity  temperature and salt resistance  core displacement experiment

摘要:

目的 以甲酸、甲醛、长链伯胺、环氧氯丙烷、甲醇和三氯甲烷为原料制备3种两性Gemini表面活性剂[(2,2'-硫酸钠-3,3'-烷基二甲基氯化铵)-N,N-丙烷基]甲胺(C₁₂SAPA、C₁₄SAPA和C₁₆SAPA)。方法 对产物结构进行了表征,比较了不同疏水链长度的表面张力、Krafft点和热稳定性,考查了3种两性Gemini表面活性剂抗温性、降低界面张力能力和提高采收率效果。通过FTIR和¹H-NMR确认了目标产物的合成。结果 随着疏水链从C₁₂H₂₅ 增加到C₁₆H₃₃,临界胶束浓度(CMC)减小,γCMC表面张力增加。随着疏水链的增加,Krafft点增加,在9 ℃以上具有良好的溶解性。3种两性Gemini表面活性剂(C₁₂SAPA、C₁₄SAPA和C₁₆SAPA)的抗温能力分别可达153 ℃、157 ℃和150 ℃；抗盐性大小为:C₁₄SAPA＞C₁₂SAPA＞C₁₆SAPA,C₁₄SAPA抗盐性达到 5×10⁴ mg/L。降低油/水界面张力能力大小为:C₁₂SAPA＞C₁₄SAPA＞C₁₆SAPA,C₁₂SAPA和C₁₄SAPA效果更好,降低油/水界面张力能达到10-2的数量级。模拟油藏地层环境下,3种两性Gemini表面活性剂分别可提高采收率12.63%、10.91%和9.87%。结论 合成的3种两性Gemini表面活性剂具有良好的表界面活性和驱油性能,在油藏提高采收率领域具有广泛的应用潜力。 

Abstract:

Objective A new sulfate-quammonium amphoteric Gemini surfactants[(2,2'-sodium sulfate-3,3'-alkyl dimethyl ammonium chloride)-N,n-propane] methylamine with hydrophobic chains(C₁₂SAPA, C₁₄SAPA and C₁₆SAPA) were prepared with formic acid, formaldehyde, long-chain tertiary amine, epichlorohydrin, chlorosulfone and NaOH. Methods The structure of the products were characterized, then the effects of different hydrophobic chain lengths on surface tension, Krafft point and thermal stability were compared, and the temperature resistance, interfacial tension reduction and EOR effects of three amphoteric Gemini surfactants were investigated. The target products were confirmed by FTIR and ¹H-NMR. Results As the hydrophobic chain increases from C₁₂H₂₅ to C₁₆H₃₃, the critical micelle concentration (CMC) decreases, and γCMC surface tension increases. With the increase of hydrophobic chain, Krafft point increases and has good solubility above 9 ℃. The temperature resistance of three amphoteric Gemini surfactants (C₁₂SAPA,C₁₄SAPA and C₁₆SAPA) can reach 153 ℃, 157 ℃ and 150 ℃,respectively; The salt resistance experiment shows C₁₄SAPA＞C₁₂SAPA＞C₁₆SAPA, and the salt resistance of C₁₄SAPA reaches 50×10³ mg/L. The ability to reduce oil/water interfacial tension is C₁₂SAPA＞C₁₄SAPA＞C₁₆SAPA. C₁₂SAPA and C₁₄SAPA can reduce oil/water interfacial tension by 10-2 order of magnitude. Under the certain reservoir formation environment, the three amphoteric Gemini surfactants can enhance oil recovery by 12.63%, 10.91% and 9.87%, respectively. Conclusion sThe synthesized three amphoteric Gemini surfactants have good surface activity and excellent oil displacement performance, so they show wide application potential in the field of enhanced oil recovery.