一种甜菜碱表面活性剂对稠化酸性能的影响

The effect of betaine surfactant on the properties of gelled acid

摘要:

本文以15-溴-1-十五醇、二甲胺水、环氧氯丙烷,3-氯-2羟基丙磺酸钠为原料,通过季铵化反应得到中间体,再通过开环反应得到最终产物甜菜碱表面活性剂TAC。采用FTIR及1H NMR对其结构进行表征;通过表面张力仪、电导率仪对其进行性能测试。通过六速旋转粘度仪、流变仪、扫面电子显微镜,研究了甜菜碱表面活性剂(TAC)对稠化酸(SY)耐温性和抗剪切性能的影响。结果表明:TAC有较低的临界胶束浓度(CMC),在298.15K条件下,最低CMC为0.11mmol/L。加入质量分数为0.4%的TAC时,可显著提高稠化酸SY的耐温、耐剪切性能,溶液升温至180℃最终粘度为80.54mPa·s,继续剪切1h后最终粘度为75.48mPa·s,与不添加TAC的SY稠化酸相比表观黏度提高了77.52%。该体系可用于深井高温酸化压裂。

Abstract:

In this paper, 15-bromo-1-pentadecanol, dimethylamine water, epichlorohydrin, and sodium 3-chloro-2hydroxypropanesulfonate were used as the raw materials, and the intermediates were obtained by quaternization, and then the final product, betaine surfactant TAC, was obtained by ring-opening reaction.The structure of TAC was characterized by FTIR and 1H NMR, and its performance was tested by a surface tension meter and conductivity meter. The effect of betaine surfactant (TAC) on the temperature resistance and shear resistance of thickening acid (SY) was investigated by six-speed rotational viscometer, rheometer, and swept surface electron microscope. The results showed that TAC had a low critical micelle concentration (CMC), and the lowest CMC was 0.11 mmol/L at 298.15 K. The addition of TAC with a mass fraction of 0.4% significantly improved the temperature and shear resistance of the thickening acid SY. The final viscosity of the solution was 80.54 mPa-s when the solution was heated up to 180 ℃, and the final viscosity of the solution after continuing to shear for 1 h was 75.48 mPa-s. The apparent viscosity increased by 77.52% compared with that of SY thickening acid without TAC. This system can be used for deep-well, high-temperature acid fracturing.