在动态H_2S/CO_2体系中疏水链上的双键对咪唑啉衍生物缓蚀性能的影响

Effect of Double Bonds in Hydrophobic Chains on Corrosion Inhibition Performance of Imidazoline Derivates in Dynamic H_2S/CO_2 Environment

分别用硬脂酸、油酸、山俞酸和芥酸4种脂肪酸与二乙烯三胺合成了4种咪唑啉化合物。通过动态失重、SEM、接触角、原子力力曲线和分子动力学模拟等分析表征手段,研究了它们在动态H_2S/CO_2体系中对碳钢的缓蚀性能及其在20#碳钢表面上的吸附能力与疏水能力。结果表明,疏水链上带有双键的咪唑啉衍生物疏水效果更好,疏水链带有双键的咪唑啉衍生物其粘附力更大。用分子动力学模拟计算出4种咪唑啉衍生物在Fe(001)表面的吸附能,疏水链中带有双键的咪唑啉的吸附能都要大于疏水链中没有双键的咪唑啉的吸附能。4种缓蚀剂缓蚀性能的理论评价结果与实验结果吻合。

Four imidazoline derivates were synthesized using diethylenetriamine with stearic acid, oleic acid, n-docosanoic acid and erucic acid respectively as raw materials. Then the inhibition per- formance and adsorption capacity on the carbon steel surface and the ability of hydrophobic of the prepared derivates were studied in dynamic H2S/CO2 environment by means of dynamic weight loss test, SEM, AFM, contact angle measurement and molecular dynamics simulation. The mea- surememnt results for contact angle and AFM force showed that the hydrophobic effect is better and the adhesion force is bigger respectively for imidazoline derivatives with double bonds in their hydrophobic chains. The surface adsorption energy of the four imidazoline derivatives on the face of Fe （001） were calculated by using molecular dynamic simulation, the results indicated that the surface adsorption energy of imidazoline which has double bonds in hydrophobic chain was larger than that one without double bonds. The theoretical evaluation of corrosion inhibition performance of four imidazoline derivates accorded well with the experiment results.