磁性纳米Fe3O4@SiO2超支化大分子处理油田污水机理研究

By indoor synthesis of magnetic nanometer Fe3O4@SiO2 composite hyperbranched macromolecules, the size of magnetic nanoparticles, magnetic strength, concentration, demulsification temperature and concentration of polymer, concentration of surfactant, pH value and other factors in ternary compound flooding water were studied. The effects of surface tension, surface wettability, adsorption properties and the mechanism of the residual polymer and surfactant on the Fe3O4@SiO2 composite hyperbranched macromolecules were studied. The adsorption kinetics equations of Fe3O4@SiO2 composite hyperbranched macromolecules for polymers and oil droplets were built. The effect of magnetic nanometer Fe3O4@SiO2 composite hyperbranched macromolecule on the demulsification and flocculation process of ternary composite flooding water was studied by means of Transmission Electron Microscopy and X-ray Diffraction and Molecular Simulation. The magnetic nanometer Fe3O4@SiO2 composite hyperbranched macromolecule has the strong adsorption performance to polymer, strong degreasing ability to oil and easy to use magnetic separation and other characteristics on treating the sewage water of ternary compound flooding. A new technology can be provided to treat the oilfield ternary compound flooding water efficiently.

通过室内合成磁性纳米Fe3O4@SiO2复合超支化大分子，研究磁性纳米颗粒大小、磁性强弱、添加浓度、破乳温度以及三元复合驱污水中聚合物浓度、表面活性剂浓度、pH值等因素对破乳、絮凝效果的影响；研究磁性纳米Fe3O4@SiO2复合超支化大分子的界面张力、表面润湿性、吸附性能及其与残余聚合物、表面活性剂的作用机理，建立Fe3O4@SiO2复合超支化大分子对聚合物和油滴的吸附动力学方程。利用透射电镜、X-衍射和分子模拟等手段研究磁性纳米Fe3O4@SiO2复合超支化大分子对三元复合驱污水的破乳絮凝过程；利用磁性纳米Fe3O4@SiO2复合超支化大分子对油田三元复合驱污水中聚合物的强吸附性能，强除油能力，且易利用磁力分离等特点，为高效处理油田三元复合驱污水提供一种新技术。

三元复合驱采油技术在各大油田尤其是大庆油田应用广泛，三元复合驱采油技术在提高原油采收率的同时，也产生了大量的三元复合驱污水。三元复合驱污水性质稳定，破乳困难，破乳后污水中含油率高，水体中机械杂质沉降速度慢，絮凝困难，研究开发对油田三元驱污水具有优良性能的磁性纳米颗粒复合超支化分子材料，使其具有高的表面活性、良好的吸附性和易分离等优点，提高除油率、加快絮凝速度，对三元复合驱污水净化效果具有巨大的应用与经济价值。.利用单质硅粉发生水解生成的SiO2沉积在磁性纳米Fe3O4表面，采用两步法合成了氨丙基改性的磁性Fe3O4@SiO2纳米颗粒，其表面含有丰富的氨基，可与具有不同官能团的超支化分子接枝，制备了5类15种不同结构的磁性纳米Fe3O4@SiO2复合超支化大分子（h-PAMAM1至h-PAMAM15）。考察投料比、反应温度、反应时间、添加剂及其加量对合成磁性纳米Fe3O4@SiO2复合超支化大分子产率及形状的影响，利用TEM、X-衍射等手段对其结构进行了表征。以室内合成的15种h-PAMAM为破乳剂，添加量40mg/L时，脱油率大于90%，添加量为12mg/L，HPAM去除率为93.8%，表面活性剂剩余含量为5.7ppm，添加量从10mg/L增加到40mg/L时，排液时间由12.84s缩短至5.32s。h-PAMAM对HPAM的吸附符合准二级动力学模型，表明h-PAMAM对HPAM的吸附作用以化学吸附为主。使用Materials Studio2017 R2软件进行模拟，加入h-PAMAM混合体系的总能量下降率为58.4%，多数絮体的尺寸达几百微米，絮体的磁响应性非常强，在磁场作用下，会迅速向磁场方向移动，数分钟内就可以实现彻底分离。.发表学术论文 11篇（SCI检索8篇，EI检索1篇），申请专利1项。