摘要
依据轨道能量理论，结合多齿配体与金属离子形成的五元或六元环鳌合物很稳定的特性，将多个具有缓蚀作用的官能团或结构连接到一个分子上，设计了一种具有缓蚀作用的硫脲基咪唑啉分子。以油酸、多乙烯多胺、硫脲为原料，合成了橙黄色硫脲基咪唑啉，并用红外光谱进行了结构表征。以合成的硫脲基咪唑啉为缓蚀剂主剂，复配表面活性剂、吡啶、甲醛、丙炔醇等，得到防H2S腐蚀的缓蚀剂XL-1。缓蚀剂XL-1具有良好的缓蚀性能，在25℃、H2S质量浓度2500 mg/L、XL-1加量0.25%时，碳钢腐蚀速率为0.013 mm/a，缓蚀率达95.3%。温度从25℃升至90℃，碳钢腐蚀速率从0.007 mm/a增至0.023 mm/a，缓蚀率从95.3%降至89.0%，抗温达90℃。随NaCl加量的增大，碳钢腐蚀速率增大，缓蚀率降低。在XL-1加量0.5%、NaCl质量分数10.0%、H2S加量2500 mg/L、腐蚀温度55℃的条件下，H2S对碳钢的腐蚀速率为0.027 mm/a，缓蚀率为87.3%。与川渝地区地层水、常用入井液或化学剂混合后，分散均匀，不分层，碳钢缓蚀率大于92%，相容性良好，适用于含硫气田的化学防腐作业。
Abstract
A five-membered or six-membered ring chelate formed by polydentate ligands and metal ions was very stable. Based on the orbital energy theory, the thioureido imidazoline molecule was designed by connecting several groups or structures which had inhibition function to a molecule. Imidazoline derivatives whose colour was orange was synthesized by polyethylene polyamine, oleic acid and thiourea. The structure was characterized by infrared spectroscopy. Anti-H2S corrosion inhibitor XL-1 was obtained by mixing synthetic thioureido?imidazoline with surfactants, pyridines, aldehydes and acetylenic alcohols. The corrosion inhibition effect of XL-1 was good. On the condition of 2500 mg/L H2S and 0.25% XL-1, the inhibition efficiency of XL-1 was 95.3% and corrosion rate of carbon steel was 0.013 mm/a at 25℃. XL-1 had good resistance of high temperature (90℃). When the temperature rose from 25℃ to 90℃, the corrosion rate of carbon steel increased from 0.007 mm/a to 0.023 mm/a, and the inhibition efficiency decreased from 95.3% to 89.0%. The corrosion rate of carbon steel increased, and the inhibition efficiency decreased with increasing dosage of NaCl. Under the condition of 0.5% XL-1, 10% mass fraction of NaCl, 2500 mg/L H2S and 55℃ corrosion temperature, the corrosion rate of H2S to carbon steel was 0.027 mm/a and the inhibition efficiency was 87.3%. When XL-1 mixed with common drilling fluids, chemical agents, and formation water in regions of Sichuan and Chongqing, there was no separation and the inhibition efficiency was above 92%, which showed a good compatibility. This corrosion inhibitor could be widely applied in all sorts of chemical anti-corrosion operations in sour gas fields.
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