School of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu, Sichuan 610500, China E-mail:
Research Institute of Petroleum Engineering Technology, Sinopec Jiangsu Oilfield Branch, Yangzhou, Jiangsu 225009, China.
Water Sci Technol. 2019 May;79(9):1648-1656. doi: 10.2166/wst.2019.154.
There are residual polymers in the oily wastewater produced from polymer flooding (OWPF); keeping the residual polymer in the water during the flocculation is meaningful and challenging. In this paper, a selective flocculant (denoted as PDC10) which can remove the oil while keeping partially hydrolyzed polyacrylamide (HPAM) in water was prepared by copolymerization of decyl two methyl vinylbenzyl ammonium chloride (C10MVBA) and dimethyl aminopropyl methacryamide (DMAPMA). By using oil removal and HPAM retention as evaluation indexes, the synthesis condition of PDC10 was optimized. The optimum PDC10 exhibited oil removal of 98.0% and HPAM retention of 80.5%. Its HPAM retention is much higher than that of a regular cationic flocculant. Measurements of zeta potential, interfacial tension, interfacial dilational modulus and a dual polarization interferometry (DPI) test were carried out for investigating the flocculation mechanism of PDC10. The mechanism of PDC10 was that it can bridge and flocculate oil droplets by electrostatic interaction and hydrophobic interaction. It also preferred to distribute at the interface, and its interaction with HPAM in bulk water was weak, which confirms its selective flocculation properties.
聚合物驱采出污水（OWPF）中含有残留聚合物；在絮凝过程中保持水中残留聚合物具有重要意义，同时也极具挑战性。本文通过共聚反应合成了一种选择性絮凝剂（PDC10），可以在去除油的同时将部分水解聚丙烯酰胺（HPAM）保留在水中。该絮凝剂以十二烷基二甲基乙烯基苄基氯化铵（C10MVBA）和二甲氨基丙基甲基丙烯酰胺（DMAPMA）为共聚单体。以除油率和 HPAM 保留率为评价指标，优化了 PDC10 的合成条件。最佳 PDC10 的除油率为 98.0%，HPAM 保留率为 80.5%。其 HPAM 保留率明显高于常规阳离子絮凝剂。通过测量动电位、界面张力、界面扩张模量和双偏振干涉（DPI）测试，研究了 PDC10 的絮凝机理。PDC10 的絮凝机理是通过静电相互作用和疏水相互作用桥联和絮凝油滴。它也倾向于分布在界面上，与水中的 HPAM 相互作用较弱，这证实了其选择性絮凝特性。
