CO_2气液两相缓蚀剂SM-12B及其性能评价

Preparation and Evaluation of Corrosion Inhibitor SM-12B for Liquid and Gas Phases of Carbon Dioxide

针对CO_2气液两相腐蚀的特点,通过合成双咪唑啉季铵盐和多单元吗啉环己胺缓蚀剂,再与含硫有机物及炔醇类缓蚀剂进行复配,得到抑制CO_2腐蚀的气液两相缓蚀剂SM-12B。通过失重法研究了SM-12B缓蚀剂在模拟气田采出液中的缓蚀率,用极化曲线及X射线衍射(XRD)等方法研究了SM-12B缓蚀剂的缓蚀机理。结果表明,使用400 mg/L的SM-12B缓蚀剂,在温度为90～110℃之间,其气相缓蚀率达到71.57%以上,液相缓蚀率达到80.82%以上;适用于CO_2分压低于1.0 MPa的CO_2腐蚀环境。SM-12B缓蚀剂浓度为300～1000 mg/L时,其缓蚀作用类型为以阳极为主的混合型缓蚀剂;腐蚀产物为FeCO_3。

Quaternary ammonium bio-imdazoline and polyunit morpholine cyclohexylamnonium moiety were synthesized firstly and then complexed with sulfur-containing organic compounds and acetylenic alcohol corrosion inhibitor for preparing the inhibitor SM-12B which could inhibit the corrosion of CO2 gas-liquid two phases. Weight loss tests indicated that the inhibition rate of gas corrosion was more than 71.57% and inhibition rate of liquid phase corrosion was more than 80. 82% when SM-12B was 400 mg/L and the temperature was between 90 ℃ and 110 ℃. SM-12B was suitable to corrosion environment in which carbon dioxide partial pressure was lower than 1.0 MPa. The results of polarization curves and X-ray diffraction （XRD） indicat that SM-12B is a mixed type of inhibitor which mainly inhibit anodeio reaction; and the corrosion product was FeCO3 when the concentration of corrosion inhibitior SM-12B was between 300 and 1000 mg/L.