用于油田含聚污水处理的铋基光催化材料研究

发布时间：2018-01-30 01:22

本文关键词： 油田污水部分水解聚丙烯酰胺光催化铋基氧化物　出处：《西南石油大学》2015年硕士论文　论文类型：学位论文

【摘要】：随着聚合物(主要为部分水解聚丙烯酰胺)驱油的广泛应用,在大大增加石油采出率的同时随之带来了关于含聚油田污水的处理问题。部分水解聚丙烯酰胺(HPAM)会带来污水自然沉降困难、絮凝剂作用变差、器械的磨损和破坏、以及水源的污染等问题。因此,处理这些含聚油田污水成为保护环境和维持采油工业的重要课题,其中光催化处理油田污水以其清洁、彻底的优点受到了广泛瞩目。本文以光催化降解部分水解聚丙烯酰胺的铋基光催化剂为研究重点,采用水热法和溶胶-凝胶法制备铋基光催化剂,采用X射线衍射图谱(XRD)、X射线光电子能谱(XPS)、扫描电子显微镜(SEM)、能量色散X射线谱(EDXS)等分析手段对样品进行表征,利用淀粉-碘化隔法、化学需氧量测试(COD)、总有机碳(TOC)分析仪测试对部分水解聚丙烯酰胺的浓度进行分析。主要研究了W/Mo掺杂对BiVO4光催化性能的影响,以及其降解部分水解聚丙烯酰胺的性能研究；薄片状和花状Bi2WO6降解模拟油田污水的性能比较,以及聚丙烯酰胺浓度、pH、以NaHCO3、Na2CO3、NaCl、Ca2+、Mg2+、Al3+的存在对薄片状Bi2WO6光催化降解部分水解聚丙烯酰胺的影响；漂珠负载Bi2WO6/BiVO4异质结的制备及光催化降解模拟油田污水。主要研究结果如下： 1.发现了W/V摩尔比为0.5%W和1.5%Mo共掺杂的BiVO4共掺杂能使得光电测试瞬态光电流增大为1.7×10-7A/cm2,几乎是纯相BiVO4的6倍(0.3×10-7A/cm2)。在300W氙灯全光谱照射下对500mg/L,分子量为300万的聚丙烯酰胺的降解率3h内能达到43%,显著高于未掺杂的18%,COD去除率能达到65%,通过测试矿化度能达到40%。配置含油量为1000mg/L, HPAM量为500mg/L的模拟油田污水。全光谱下照射3h,0.5%W和1.5%Mo共掺杂的BiVO4能使其COD去除率达到的40%。其降解机理主要是·OH的氧化作用。 2.薄片状Bi2WO6全光谱下3h对模拟油田污水的COD去除率为55%,降解效果优于花状Bi2WO6(52%)。聚丙烯酰胺的降解随着浓度升高而降低；聚丙烯酰胺在碱性条件下降解率较差；NaHCO3和Na2CO3也会影响薄片状Bi2WO6对聚丙烯酰胺的降解,使其降解减弱。NaCl的存在会造成聚丙烯酰胺降解率的降低,由50%降低为45%。金属离子的存在会显著影响聚丙烯酰胺浓度的变化,其影响大小的排序为Na+Ca2+Mg2+Al3+,其中Al3+对光催化降解聚丙烯酰胺的影响显著。 3.利用溶胶凝胶法制备漂珠负载的Bi2WO6/BiVO4,并通过调节W/V的摩尔质量比控制复合量。发现30%Bi2WO6与BiVO4复合后,在可见光下能使亚甲基蓝MB(10mg/L)在3h内降解率达到100%,相对于未复合的BiVO4性能具有显著提高。其对配置含油量为1000mg/L,HPAM量为500mg/L的模拟油田污水也具有较好的降解效果,可见光下3h其COD去除率为58%。以漂珠作为载体,除了提高光催化活性以外,还可提高其重复利用率。
[Abstract]:With the widespread application of polymer (mainly partially hydrolyzed polyacrylamide) flooding. At the same time, it brings about the problem of treating the sewage containing polymer oil field. The partial hydrolysis of polyacrylamide (HPAM) will bring about the difficulty of natural settling of sewage and the function of flocculant becomes worse. Therefore, it is an important issue to protect the environment and maintain the oil recovery industry to deal with these oil field sewage, in which photocatalytic treatment of oilfield sewage for its cleanliness. The advantages of thoroughness have been widely noticed. In this paper, bismuth-based photocatalysts for the degradation of partially hydrolyzed polyacrylamide were studied. Bismuth based photocatalysts were prepared by hydrothermal method and sol-gel method. X-ray diffraction patterns (XRD) were used to prepare bismuth based photocatalysts. The samples were characterized by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDXS). The concentration of partially hydrolyzed polyacrylamide was analyzed by chemical oxygen demand (COD) and total organic carbon (TOC) analyzer. The effects of W / Mo doping on the photocatalytic performance of BiVO4 and the degradation of partially hydrolyzed polyacrylamide were studied. The properties of flake and flower-like Bi2WO6 in degradation of simulated oilfield wastewater and the pH value of polyacrylamide in NaHCO3Na2CO3- NaClCO3- NaCl-Ca2 + Mg2 were compared. The effect of the presence of Al3 on the photocatalytic degradation of partially hydrolyzed polyacrylamide (PAM) by flake Bi2WO6; Preparation and photocatalytic degradation of simulated oilfield wastewater by Bi2WO6/BiVO4 heterojunction supported on bleach beads. The main results are as follows: 1. It is found that BiVO4 co-doping with W / V molar ratio of 0.5 W and 1.5Mo can increase the transient photocurrent to 1.7 脳 10 ~ (-7) A / cm ~ 2. It is almost 6 times that of pure phase BiVO4 (0.3 脳 10 ~ (-7) A / cm ~ (-2) 路cm ~ (-2)). Under the full spectral irradiation of 300W xenon lamp, 500 mg / L. The degradation rate of polyacrylamide with molecular weight of 3 million can reach 43% within 3 h, which is significantly higher than that of unadulterated polyacrylamide, which can reach 65%. The salinity can reach 40mg / L, and the simulated oilfield wastewater with oil content of 1000mg / L and HPAM of 500mg / L is set up and irradiated for 3 hours under full spectrum. BiVO4 doped with 0.5W and 1.5W Mo can make the removal rate of COD reach 40%. The degradation mechanism is mainly the oxidation of 路OH. 2. The COD removal rate of simulated oilfield wastewater in 3 h under the full spectrum of thin slice Bi2WO6 is 55%. The degradation effect of polyacrylamide was better than that of flower-like Bi2WO _ 6N _ (52). The degradation of polyacrylamide decreased with the increase of concentration. The degradation rate of polyacrylamide was poor in alkaline condition. NaHCO3 and Na2CO3 can also affect the degradation of polyacrylamide by Bi2WO6. The degradation of polyacrylamide will be reduced by the presence of NaHCO3 and Na2CO3. The concentration of polyacrylamide was significantly affected by the presence of metal ions from 50% to 45. The order of influence was Na Ca2 Mg2 Al3. The effect of Al3 on photocatalytic degradation of polyacrylamide was significant. 3. Bi2WO6/BiVO4 supported on bleach beads was prepared by sol-gel method. By adjusting the molar ratio of W / V to control the amount of the compound, it was found that 30% Bi2WO6 was combined with BiVO4. Under visible light, the degradation rate of methylene blue MBN (10mg / L) reached 100% in 3 h. Compared with the uncompounded BiVO4, it has a better degradation effect on simulated oilfield wastewater with oil content of 1000mg / L and HPAM of 500mg / L. The removal rate of COD was 58% under visible light for 3 h. Using bleach beads as carrier could not only improve the photocatalytic activity, but also improve the reutilization rate.
【学位授予单位】：西南石油大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X741;TB34

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