N,N′-双(十八烷基二甲基)-1,2-二溴化己二铵盐双子表面活性剂的合成及应用研究

Synthesis and Applied Research of N,N'-Bis (Octadecyl dimethyl)-1,2-dibromide-dihexyl Ammonium Salt

摘要:

以十八叔胺与1,6-二溴正己烷为原料合成了双子表面活性剂N,N′-双(十八烷基二甲基)-1,2-二溴化己二铵盐（C18-6-C18•2Br-）。产物经红外光谱（IR）、核磁共振氢谱（1H NMR）和元素分析等进行了分析，证明所得产物即为目标产物。通过表面张力法测定了C18-6-C18•2Br-和十八烷基三甲基氯化铵（1831）的临界胶束浓度，测试结果表明：C18-6-C18•2Br-具有较高的表面活性，其临界胶束浓度为2.13×10-5mol•L-1，CMC为39.1mN•m-1，C18-6-C18•2Br-的临界胶束浓度较1831低一个数量级。对C18-6-C18•2Br-和水杨酸钠、氯化钾组成的清洁压裂液体系进行了性能研究。结果表明：双子表面活性剂在较低浓度时可形成稳定耐高温的胶束，具有良好的耐剪切能力，在110℃、170s-1下连续剪切60min，表观黏度依然保持在60 mPa•s左右；破胶性能良好，压裂液遇到煤油和盐水后可迅速破胶，残渣几乎为零，可较大程度地减小对地层的伤害；岩心伤害实验说明该压裂液体系对地层的伤害较小。说明该压裂液是一种耐温性能良好、黏弹性较好的低伤害压裂液。

Abstract:

An ammonium Gemini surfactant (C18-6-C18•2Br-) was synthesized from N,N-Dimethyloctadecylamine and 1,6-dibromohexane. The surfactants were characterized via IR spectra, 1H NMR spectra and elemental analysis，and the results prove that they are all the objective products．The critical micelle concentration of C18-6-C18•2Br- and Octadearyl dimethyl ammonium chloride (1831) were characterized by surface tension. The results indicate that C18-6-C18•2Br- has good surface active,and its critical micelle concentration is 2.13×10-5mol•L-1, The critical micelle concentration of C18-6-C18•2Br- was lower than the critical micelle concentration of a magnitude of octadearyl dimethyl ammonium chloride (1831).Study on clean fracturing fluid using C18-6-C18•2Br-, sodium salicylate and potassium chloride was done inlaboratory. The experimental results show that Gemini surfactants can be formed stable micelles at low concentrations.in high temperature, and it has good resistance to shear capacity, at 110 ℃ in 170 s-1 shear rate, shear continuous 60 min, viscosity remains at 60 mPa•s at least; has good performance of gelout, Fracturing fluids encountered kerosene and salt water can quickly break the glue, and the residue is almost zero, with a small formation damage; Core damage experiment shows that formation damage is small of this fracturing fluid system. The fracturing fluid hsa good heat resistance and viscoelastic.