Fe₃O₄/导电高分子复合材料的合成与防腐防蜡性能

【作者】 刘汉斌；

【导师】 庄稼；

【作者基本信息】 西南石油大学 ， 油气田材料与应用， 2011， 硕士

【摘要】 管道腐蚀和结蜡是长期以来制约油气管道集输安全性和输送效率的两个重要因素。管道发生腐蚀破坏,轻则造成原油泄漏,重则引发爆炸等安全事故；而因管道结蜡,在集输过程中需要定期进行清蜡作业,严重影响管道输送效率的提高,能否将二者结合,制备一种兼具防腐和防蜡性能的多功能管道内涂层材料?本文作了大胆的探索,制备了Fe304/导电高分子复合材料,将其加入到醇酸树脂清漆中,得到一种复合涂层,并考察了这种复合涂层的防腐和防蜡性能,证明这种复合涂层用于管道内涂层具有可行性。具体研究工作包括：(1)以FeCl3和FeSO4为铁源,以NH3-H20和N2H4·H20为沉淀剂体系,通过共沉淀法合成了Fe304,确定最佳合成条件为Fe3+：Fe2+=1.75：1,反应温度70℃。XRD和FT-IR分析表明产物纯净,具有典型的反尖晶石结构,晶粒尺寸10nm左右,振动样品磁强计(VSM)分析表明其单位质量的饱和磁场强度为61.143emu/g。对Fe304进行了表明修饰研究,结果表明十二烷基苯磺酸钠(SDBS)具有良好的修饰效果,修饰后的Fe3O4水溶液均匀分散不分层,激光粒度仪分析表明SDBS对Fe304的粒径有显著的调控作用,结合红外和Zeta电位分析,认为这是因为SDBS与Fe304形成了O—0共价键作用。(2)在已合成Fe304的基础上制备了Fe3O4/PTH (PTH,聚噻吩)复合材料,并对其进行了Raman, FT-IR, EDS, TEM, Zeta和TG-SDTA分析,结果表明噻吩单体在Fe304表面成功聚合成聚噻吩,得到的复合材料具有明显的核壳结构,核相为Fe3O4,粒径约为14nm；壳相为PTH,厚度约为3～4nm。将Fe3O4/PTH复合材料加入到醇酸树脂清漆中得到复合涂层,加速腐蚀实验和静态防蜡实验结果表明当Fe304/PTH复合材料的质量百分量在0.8-1%时,涂层兼有良好的防腐和防蜡性能,附着力和漆膜冲击力测试结果表明Fe304/PTH复合材料的加入对涂层附着力没有影响,抗冲击强度稍有降低。(3)为提高防蜡性能,对Fe304进行了Ni掺杂研究,制备了Ni doped Fe3O4/PTH复合材料,XPS分析表明在该复合材料中Ni元素的掺杂量为0.8%,VSM分析表明该复合材料的单位质量饱和磁场强度为73.456emu/g,较未掺杂的纯Fe304提高了20.14%。将固体石蜡溶解在液体石蜡中模拟原油结蜡过程,设计了模拟结蜡试验,用旋转黏度计测定了20%固体石蜡的液体石蜡溶液的析蜡点为40℃。在析蜡点温度,将涂有涂层的试片放入其中,反复测定其增重量,结果表明清漆涂层的平均增重量为0.0891g,加入了Fe304复合涂层的平均增重量为0.0803g,加入了Ni doped Fe3O4/PTH的复合涂层的平均增重量为0.0743g,增重量即试片表面的石蜡附着量,由此判断加入了Ni dopedFe3O4/PTH的复合涂层表面石蜡附着量最小,具有最佳的防蜡效果。(4)为验证Ni doped Fe3O4/PTH复合材料防腐蚀的有效性,选择与目前已经市场化应用的防腐蚀材料聚苯胺(PANI)进行对比,制备了Ni doped Fe3O4/PANI复合材料,电化学阻抗(EIS)测试结果表明Ni doped Fe3O4/PTH复合材料的防腐蚀性能与Ni doped Fe3O4/PANI复合材料相当。更多还原

【Abstract】 The corrosion and paraffin deposition of the pipeline were two important factors which restricted the security and efficiency of gas and oil transportation. Corrosion damages in pipeline caused crude oil leakage even explosions and the paraffin deposition required to remove regularly, both seriously affected the transportation efficiency. Can we prepare a kind of multifunctional internal coating which had the functions of anticorrosion paraffin controlling? A bold exploration was done in this paper. A composite of Fe3O4 and conducting polymers was synthesized and added into alkyd varnish to form a composite coating. After investigated the anticorrosion and paraffin controlling performance, this composite coating was demonstrated to be feasible for internal coating of pipelines. Specific researches were list as follows:(1) Fe3O4 was synthesized by co-precipitation method, using the FeCl3 and FeSO4 as iron sources, NH3·H2O and N2H4·H2O as precipitant system. The optimal condition were obtained, mole ratio of Fe3+:Fe2+was 1.75:1, reaction temperature was 70℃. FT-IR and XRD analysis showed that the product was pure and had typical anti-spinel structure with grain size of about 10nm. Vibrating sample magnetometer (VSM) analysis showed that the saturation magnetic field intensity per unit mass was 61.143emu/g. The modification of Fe3O4 showed that sodium dodecylbenzene sulfonate (SDBS) had a good modification effect, and the modified Fe3O4 aqueous solution dispersed well and was not hierarchical. The investigation of laser particle size analyzer showed that SDBS had significant regulatory effect to the particle size of Fe3O4, combined with FT-IR and Zeta potential analysis, it could figure out that the reason was O-O covalent bond between SDBS and Fe3O4.(2) Base on the synthesized Fe3O4, the composite of Fe3O4 and PTH (polythiophene) was prepared and investigated with Raman, FT-IR, EDS, TEM, Zeta and TG-SDTA. The results showed that the thiophene was successfully polymerized on the surface of Fe3O4 and the resulting composite was in the nature of core shell structure, in which the core was Fe3O4 with particle size of 14nm and the shell was PTH with thickness of 3-4nm. The composite coating was obtained with the Fe3O4/PTH composite added into alkyd varnish. Accelerated corrosion test and static paraffin control test showed that the composite coating had good performances of anticorrosion and paraffin controlling, when the mass ratio of Fe3O4/PTH composite was 0.8-1%, and the Paint adhesion and impact test results showed that the added Fe3O4/PTH composite had no influence to the adhesion, while the impact strength decreased slightly.(3) In order to increase the paraffin control performance, the Fe3O4 was doped with Ni and formed Ni doped Fe3O4/PTH composite. XPS analysis showed that the doped content was 0.8%in the composite. VSM analysis showed that the saturation magnetic field intensity per unit mass of the composite was 73.456emu/g, increased 20.14%compared with the undoped Fe3O4. To simulate the paraffin deposition, the solid paraffin was dissolved into the liquid paraffin, and the wax precipitation point was 40℃determined by rotational viscometer when the mass ratio of solid paraffin was 20%. At the temperature of wax precipitation point, the test plate coated with composite coating was immersed into, pulled out and weighted the weight increments again and again. The results showed that the average weight increment of alkyd varnish was 89.1mg, and that of composite coating added with Fe3O4 was 80.3mg and that of composite coating added with Ni doped Fe3O4/PTH was 74.3mg, indicating the composite coating added with Ni doped Fe3O4/PTH had the best paraffin controlling performance because the weight increments were the paraffin deposited on the test plates.(4) To verify the anticorrosion effectiveness of Ni doped Fe3O4/PTH composite, the comparison was carried out to the market applicated ployaniline (PANI). So the Ni doped Fe3O4/PANI composite was prepared. The electrochemical impedance spectroscopy (EIS) showed that the anticorrosion performance of Ni doped Fe3O4/PTH was comparable to the Ni doped Fe3O4/PANI.更多还原