Chen Zhiping, Wang Xiujun, Zhang Jian, Zhang Wenju, Duan Ming, Xiong Yan, Fang Shenwen
School of Chemistry and Chemical Engineering, Southwest Petroleum University 8 Xindu Avenue, Xindu District Chengdu Sichuan 610500 China
State Key Laboratory of Offshore Oil Exploitation Beijing China.
RSC Adv. 2024 Mar 8;14(12):8124-8134. doi: 10.1039/d4ra00188e. eCollection 2024 Mar 6.
Cationic polyacrylates exhibit both reverse demulsification and flotation performance, which can avoid incompatibility between the reverse demulsifier and flotation agent during treatment of produced water from offshore oilfields. In our previous work, the effect of the structure of the cationic unit on the reverse demulsification and flotation performance of cationic polyacrylates was studied. However, the structure-activity relationship of cationic polyacrylates has not been systematically studied. In this study, the relationships between the structure (acrylate type, tertiary amine type, mass ratio of acrylate to tertiary amine, and degree of cationicity), interfacial properties (surface tension, interfacial tension, zeta potential, interfacial elastic modulus, interaction force between oil droplets, and film drainage time of an oil-covered bubble), and reverse demulsification and flotation performance of cationic polyacrylates were investigated. A reduction in the elastic modulus of the oil-water interface was the key factor for good reverse demulsification performance, whereas a decrease in the film drainage time of an oil-covered bubble was the key factor for good flotation performance. Ethyl acrylate (EA) was superior to methyl acrylate (MA), and dimethylaminopropyl methacrylamide (DPM) was superior to dimethylaminoethyl methacrylate (DEM). Increases in the mass ratio of ethyl acrylate to dimethylaminopropyl methacrylamide and the degree of cationicity were beneficial for reducing the elastic modulus of the oil-water interface and the film drainage time of an oil-covered bubble. This is the first time that the structure-property-performance relationship of cationic polyacrylates has been systematically studied. A cationic polyacrylate that exhibited both good reverse demulsification performance and good flotation performance is recommended.
阳离子聚丙烯酸酯具有破乳和浮选性能，在处理海上油田采出水时可避免破乳剂与浮选剂之间的不相容性。在我们之前的工作中，研究了阳离子单元结构对阳离子聚丙烯酸酯破乳和浮选性能的影响。然而，阳离子聚丙烯酸酯的构效关系尚未得到系统研究。本研究考察了阳离子聚丙烯酸酯的结构（丙烯酸酯类型、叔胺类型、丙烯酸酯与叔胺的质量比以及阳离子度）、界面性质（表面张力、界面张力、ζ电位、界面弹性模量、油滴间相互作用力以及油包气泡的液膜排水时间）与破乳和浮选性能之间的关系。油水界面弹性模量的降低是良好破乳性能的关键因素，而油包气泡液膜排水时间的缩短是良好浮选性能的关键因素。丙烯酸乙酯（EA）优于丙烯酸甲酯（MA），甲基丙烯酰氧丙基二甲基胺（DPM）优于甲基丙烯酸二甲氨基乙酯（DEM）。丙烯酸乙酯与甲基丙烯酰氧丙基二甲基胺质量比和阳离子度的增加有利于降低油水界面弹性模量和油包气泡的液膜排水时间。这是首次对阳离子聚丙烯酸酯的结构-性质-性能关系进行系统研究。推荐了一种兼具良好破乳性能和良好浮选性能的阳离子聚丙烯酸酯。
