镍铁氧体复合材料的制备及其吸附性能研究

发布时间：2018-01-12 23:25

本文关键词：镍铁氧体复合材料的制备及其吸附性能研究　出处：《西安科技大学》2015年硕士论文　论文类型：学位论文

【摘要】：近年来,水体污染越来越严重,染料废水已成为主要的水体污染源。吸附法是最常用的一种染料废水处理技术,它效率高、成本低、操作简单,但传统的吸附剂存在再生成本高、难以回收、吸附选择性低等问题。因此,利用新型、高效、选择性高且容易回收的功能化磁性材料处理染料废水,已经越来越受到广大研究者的关注。论文分别采用水热法、原位化学氧化聚合法和化学还原法合成了活性炭(AC)/NiFe_2O_4、NiFe_2O_4/聚苯胺(PANI)、NiFe_2O_4/PANI/Ag复合材料,运用振动样品磁强计(VSM)、X射线衍射仪(XRD)、孔结构及比表面积分析、傅里叶红外光谱仪(FT-IR)等手段对镍铁氧体复合材料进行了表征和分析,并研究了其对偶氮染料的吸附性能。结果表明:离子强度对AC/NiFe_2O_4吸附甲基橙几乎没有影响,当pH=3.0,吸附剂用量为0.3g时,AC/NiFe_2O_4对甲基橙的去除率最高,可达99%以上,且吸附平衡时间仅为20min;AC/NiFe_2O_4对甲基橙的吸附符合Langmuir模型,属于单分子层吸附,由0R_L1和0.11/n0.5可知,吸附很容易进行,属于优惠型吸附;热力学行为分析表明,吸附过程是自发的、吸热的过程;AC/NiFe_2O_4对甲基橙的吸附符合假二级动力学模型,由颗粒内扩散和液膜扩散共同控制;利用0.1 mol/L NaOH溶液再生6次后的AC/NiFe_2O_4仍具有良好的磁性能和吸附甲基橙的能力,去除率达85.10%。当吸附剂用量为0.06 g,吸附温度35℃时,NiFe_2O_4/PANI对甲基橙的去除率高达96%以上,吸附时间为30 min;NiFe_2O_4/PANI对甲基橙的吸附符合Langmuir模型,属于单分子吸附,由0R_L1和01/n0.5可知,吸附很容易进行,属于优惠型吸附;热力学行为分析表明,吸附过程是自发的、吸热的过程;Ni Fe_2O_4/PANI对甲基橙的吸附过程符合假二级动力学模型,由颗粒内扩散控制;采用0.1 mol/L HCl溶液再生后的NiFe_2O_4/PANI对甲基橙的去除效果良好。NiFe_2O_4/PANI/Ag对茜素红、刚果红、甲基橙、亚甲基蓝、罗丹明B五种染料的选择性吸附结果表明,NiFe_2O_4/PANI/Ag对刚果红的吸附选择性最高。离子强度的增大促进了NiFe_2O_4/PANI/Ag对刚果红的吸附,且温度越低,吸附效果越好;NiFe_2O_4/PANI/Ag对刚果红的吸附同时符合Langmuir模型和Freundlich模型,15℃时吸附量为207.47 mg/g,由0R_L1和0.11/n0.5可知,吸附很容易进行;热力学行为分析表明,吸附过程是自发的、放热的过程,属于物理吸附;NiFe_2O_4/PANI/Ag对刚果红的吸附过程更适合用假二级动力学模型拟合,由颗粒内扩散和液膜扩散共同控制;利用0.1 mol/L HCl溶液再生后的NiFe_2O_4/PANI/Ag对刚果红仍具有一定的吸附能力。
[Abstract]:In recent years, water pollution is more and more serious, dye wastewater has become the main source of water pollution. The adsorption method is one of the most commonly used dye wastewater treatment technology, it has high efficiency, low cost, simple operation, but the existence of the traditional adsorbent regeneration of high cost, difficult recovery, low selectivity problems. Therefore, the use of new high efficiency, high selectivity, and easy recovery treatment of dye wastewater by magnetic materials, have attracted the attention of the majority of researchers were studied by using hydrothermal method, in situ chemical oxidation polymerization and chemical synthesis of activated carbon (AC) /NiFe_2O_4, NiFe_2O_4/ (PANI), polyaniline NiFe_2O_4/PANI/Ag composite materials, the use of vibration sample magnetometer (VSM), X ray diffraction (XRD), pore structure and specific surface area analysis, Fourier transform infrared spectroscopy (FT-IR) were characterized and analyzed on the composite Nie Tieyang body, and research The adsorption properties of azo dyes have been studied. The results showed that the ionic strength on the adsorption of methyl orange AC/NiFe_2O_4 has almost no effect, when pH=3.0, adsorbent dosage was 0.3g, AC/NiFe_2O_4 of methyl orange on the highest removal rate can reach more than 99%, and the adsorption equilibrium time was 20min; the adsorption of methyl orange AC/NiFe_2O_4 with the Langmuir model, which belongs to the single molecular layer adsorption by 0R_L1 and 0.11/n0.5 shows that the adsorption is easy, which belongs to the preferential adsorption behavior; thermodynamic analysis shows that the adsorption process was spontaneous and endothermic process; AC/NiFe_2O_4 adsorption of methyl orange with the pseudo two order kinetics model, jointly control the intraparticle diffusion and film diffusion; regeneration after 6 times of AC/NiFe_2O_4 have good magnetic properties and adsorption ability of using 0.1 mol/L NaOH solution, the removal rate of 85.10%. when the adsorbent dosage was 0.06 g, adsorption temperature of 35 DEG C, N IFe_2O_4/PANI of methyl orange removal rate was above 96%, the adsorption time is 30 min; the adsorption of methyl orange NiFe_2O_4/PANI with the Langmuir model belongs to the single molecular adsorption by 0R_L1 and 01/n0.5 shows that the adsorption is easy, which belongs to the preferential adsorption; thermodynamic behavior analysis showed that the adsorption process was spontaneous, endothermic process; adsorption Ni Fe_2O_4/PANI of methyl orange with the pseudo two order kinetics model, controlled by the intra particle diffusion effect; using 0.1 mol/L HCl solution regeneration after NiFe_2O_4/PANI removal of methyl orange with good.NiFe_2O_4/ PANI/Ag on Alizarin red, Congo red, methyl orange, methylene blue, selective adsorption of Luo Danming B of five kinds of dyes. The results show that the NiFe_2O_4/PANI/Ag of Congo red the highest adsorption selectivity. The increase of ionic strength to promote the adsorption of Congo red on NiFe_2O_4/PANI/Ag, and the lower the temperature, the adsorption effect is better; N The adsorption of iFe_2O_4/PANI/Ag on Congo red at the same time with the Langmuir model and Freundlich model, 15 degrees when the adsorption amount of 207.47 mg/g, by 0R_L1 and 0.11/n0.5 shows that the adsorption is easy; thermodynamic analysis shows that the adsorption process is spontaneous, exothermic process is physical adsorption; the adsorption process of NiFe_2O_4/PANI/Ag on Congo red is more suitable for false the two level dynamic model fitting, jointly control the intraparticle diffusion and film diffusion; using 0.1 mol/L HCl solution after regeneration of NiFe_2O_4/PANI/Ag still has certain adsorption capacity of Congo red.

【学位授予单位】：西安科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X788;O647.3

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