新型衣康酸三元共聚物对碳酸钙的阻垢性能及抑制机理的分子动力学模拟  

Molecular Dynamics Simulation of Scale Inhibition Performance and Inhibition Mechanism of New Itaconic Acid Terpolymer on CaCO 3

作　　者：余嵘 田智岗 雷欢 成柯瑶 付少华 YU Rong;TIAN Zhigang;LEI Huan;CHENG Keyao;FU Shaohua(College of Urban Planning and Municipal Engineering,Xi′an Polytechnic University,Xi′an 710048,China)

机构地区：[1]西安工程大学城市规划与市政工程学院,陕西西安710048

出　　处：《石油学报（石油加工）》2023年第6期1390-1402,共13页Acta Petrolei Sinica(Petroleum Processing Section)

基　　金：陕西省重点研发计划项目(2021NY-188)基金资助。

摘　　要：以衣康酸(IA)、甲基丙烯磺酸钠(SMAS)、乙酸乙烯酯(VAc)为单体制备了新型衣康酸共聚物阻垢剂IA-SMAS-VAc,与常规阻垢剂聚丙烯酸(PAA)进行阻垢性能比较。为探究阻垢剂与结垢晶体表面的作用机理,借助分子动力学模拟方法,对IA-SMAS-VAc与PAA在水溶条件下影响碳酸钙方解石晶体生长的微观性能差异进行对比。结果表明:在实验溶液pH值为8、反应温度为80℃、反应时间为10 h的条件下,共聚物IA-SMAS-VAc的阻垢效率最大为95.15%,阻垢效果优于PAA;2种阻垢剂IA-SMAS-VAc和PAA均与方解石(110)和(104)晶面紧密贴合,且|E int|(110)>|E int|(104),2种阻垢剂对方解石晶体的生长以抑制(110)晶面为主。径向分布函数g(r)Ca—O体现出阻垢剂中氧原子与方解石晶体中Ca^(2+)形成离子键的强弱,共聚物IA-SMAS-VAc与方解石(110)和(104)晶面上g(r)Ca—O(110)>g(r)Ca—O(104),并且g(r)Ca—O(IA-SMAS-VAc)>g(r)Ca—O(PAA),说明IA-SMAS-VAc与方解石晶体间形成的Ca—O键更牢固,从而在微观层面证实共聚物阻垢剂IA-SMAS-VAc的阻垢性能优异。A new itaconic acid copolymer scale inhibitor IA-SMAS-VAc was prepared with itaconic acid(IA),sodium methacrylate sulfonate(SMAS)and vinyl acetate(VAc)as monomers,and its scale inhibition performance was compared with that of the conventional scale inhibitor polyacrylic acid(PAA).In order to explore the action mechanism of scale inhibitor and scaling crystal surface,the difference in micro performance between IA-SMAS-VAc and PAA on the growth of CaCO_(3)calcite crystal in water solution was compared by means of molecular dynamics simulation.The results show that the maximum scale inhibition efficiency of the copolymer IA-SMAS-VAc is 95.15%at pH=8,reaction temperature of 80℃and reaction time of 10 h,and the scale inhibition effect is better than that of PAA;the two scale inhibitors IA-SMAS-VAc and PAA are closely bound to the crystal planes of calcite(110)and(104),|E int|(110)>|E int|(104),and the two scale inhibitors mainly inhibit the growth of calcite crystal plane(110).The radial distribution function g(r)Ca—O shows the strength of the ionic bond between the oxygen atom in the scale inhibitor and Ca^(2+)in the calcite crystal,and the results show that g(r)Ca—O(110)>g(r)Ca—O(104)and g(r)Ca—O(IA-SMAS-VAc)>g(r)Ca—O(PAA)on the crystal planes of copolymer IA-SMAS-VAc,calcite(110)and(104),indicating that the Ca—O bond formed between IA-SMAS-VAc and calcite crystal is stronger.This proves that the copolymer scale inhibitor IA-SMAS-VAc has excellent scale inhibition performance at the microscopic level.

关 键 词：衣康酸 共聚物阻垢剂 碳酸钙 方解石晶体 分子动力学模拟 径向分布函数 相互作用能 

分 类 号：TQ085[化学工程]