磺基甜菜碱Gemini表面活性剂的合成与应用性能

Synthesis and application properties of a sulfobetaine Gemini surfactant

为了改善储层的非均质性差异,有效提高碳酸盐储层的酸化解堵效果,以长链烷基二甲基叔胺、3-氯-2-羟基丙烷磺酸钠和1,4-二溴丁烷为原料,通过两步反应合成了一系列磺基甜菜碱双子表面活性剂(2Cn-SGS,其中n为疏水链中碳原子数,n=12,14,16,18)自转向酸主剂。以2C16-SGS为例,采用FTIR对中间产物(C16-SGS)及2C16-SGS的结构进行表征。通过表面张力法测定2Cn-SGS的表面活性,结果表明,2Cn-SGS具有良好的表面活性,随着疏水链的增长,2Cn-SGS的CMC和表面张力均减小,且胶束化能力增强。可用于黏弹性表面活性剂自转向酸酸化技术,具有良好的转向分流能力,优选配方为4%2C16-SGS+20%盐酸+20%Ca^2+,而且高黏胶束遇煤油等烃类能够自动破胶降黏,易返排对地层无伤害。

In order to change the heterogeneity difference,improve the acidizing and unplugging effect of carbonate reservoir,a series of sulfobetaine Gemini surfactants (2Cn-SGS,where n is the number of carbon atoms in the hydrophobic chain,n=12,14,16,18) were synthesized by a two-step reaction using long chain alkyl dimethyl tertiary amine,3-chloro-2-hydroxypropane sulfonic acid sodium and 1,4-dibromobutane as raw materials.Taking 2C16-SGS as an example,the structures of mid product (C16-SGS) and 2C16-SGS were characterized by FTIR.Surface activity of 2Cn-SGS was analyzed by surface tension method.The results show that 2Cn-SGS have good surface activity,and the CMC and surface tensions of 2Cn-SGS decrease with the increase of hydrophobic chain,and the micellization ability is enhanced.It can be used in viscoelastic surfactant self-steering acidification technology,with good steering and shunting ability.The optimal formula is 4% 2C16-SGS+20% hydrochloric acid + 20% Ca^2+.The high viscosity gel of acidizing system is easy to break when mixing with hydrocarbons such as kerosene.It is easy to backflow and has no damage to the formation.