电絮凝与花生壳、改性稻壳吸附耦合技术去除孔雀石绿的研究

发布时间：2018-01-19 23:56

本文关键词： 电絮凝花生壳 NaOH改性稻壳吸附孔雀石绿　出处：《吉林大学》2017年硕士论文　论文类型：学位论文

【摘要】：我国的染料废水排放量大、治理技术不完善使染料废水的危害愈加严重,染料废水的治理成为热点问题。电絮凝技术因为其设备简单、环境友好、易于自动控制近年来成为研究热点,但其存在能耗高,电极易钝化等问题。本研究在传统电絮凝的基础上分别加入花生壳、改性稻壳作为吸附剂,构造电絮凝生物吸附剂吸附耦合体系处理孔雀石绿(MG)废水,意图在较短的处理时间和较低的能耗下获得较高的去除率。本文先制备花生壳(PS)、Na OH改性稻壳吸附剂(Na OH-RH),采用扫描电镜(SEM)、傅里叶转换红外光谱(FT-IR)、比表面积测试(BET)等手段对吸附剂进行表征,表明其具有良好的吸附性。用质量滴定法分别测定p Hpzc,结果表明花生壳吸附阳离子染料的适宜p H为p H5.8,Na OH改性稻壳作吸附剂的适宜p H为p H7.4。探讨电絮凝花生壳吸附耦合体系中电流密度、花生壳投加量、溶液初始p H值、孔雀石绿溶液初始浓度等因素对去除效率的影响,得出最佳电流密度为2m A/cm2,溶液最佳初始p H值为7,花生壳最佳投加量为5g/L,最佳孔雀石绿初始浓度为50mg/L,在此条件下,5min内,去除效率可达98.2%,比传统电絮凝体系提高了22.4%,反应时间缩短了55min,比单独花生壳吸附体系去除效率提高了18.1%,反应时间缩短了35min。在上述体系的最佳电流密度和最佳孔雀石绿溶液初始浓度下,探讨电絮凝改性稻壳体系中改性固液比、改性时间、溶液初始p H值、改性稻壳投加量对去除效率的影响。得出最佳条件为:固液比1:8,改性时间30min,溶液初始p H值为8,改性稻壳投加量为3g/L,在此条件下,10min内,孔雀石绿的去除效率可达97.5%,比传统电絮凝体系提高了21.7%,反应时间缩短了50min,比单独Na OH改性稻壳吸附体系的去除率提高了17.2%,反应时间缩短了30min。计算不同体系的单位能耗和单位电极材料消耗,结果表明,电絮凝花生壳吸附耦合体系的单位能耗和单位电极材料消耗比传统电絮凝体系降低了97.4%,电絮凝Na OH改性稻壳吸附耦合体系比传统电絮凝体系降低了88.9%。对吸附剂吸附过程进行吸附等温线模型拟合,表明花生壳、Na OH改性稻壳吸附过程分别符合Langmuir吸附等温模型和Freundlich吸附等温模型,吸附动力学均符合准二级动力学模型,对电絮凝体系和耦合体系进行反应动力学模型拟合,说明两种体系的反应均较符合二级动力学模型。
[Abstract]:Because of the large discharge of dyestuff wastewater in our country and the imperfect treatment technology, the harm of dyestuff wastewater becomes more and more serious, and the treatment of dyestuff wastewater becomes a hot issue. The electroflocculation technology has simple equipment and friendly environment. In recent years, easy automatic control has become a research hotspot, but it has many problems such as high energy consumption, easy passivation of electrode and so on. In this study, peanut shell was added on the basis of traditional electroflocculation, and modified rice husk was used as adsorbent. In order to get a higher removal rate of malachite green MG wastewater by using an electroflocculating biological adsorbent coupling system, a peanut hulls (PSS) was prepared in this paper. In this paper, the treatment of malachite green MG wastewater was carried out in order to obtain a higher removal rate under shorter treatment time and lower energy consumption. NaOH modified rice husk adsorbent, NaOH-RHH, was used by scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR). The adsorbents were characterized by specific surface area test (BET) and the results showed that the adsorbents had good adsorbability. The p Hpzc was determined by mass titration. The results showed that the suitable pH for the adsorption of cationic dyes from peanut shell was pH 5.8. The suitable pH of NaOH modified rice husk as adsorbent was pH 7.4. The electric current density, peanut shell dosage and initial pH value of solution were studied in the electroflocculation peanut shell adsorption coupling system. The effect of the initial concentration of malachite green solution on the removal efficiency was studied. The optimum current density was 2 m / cm 2, the initial pH value was 7, and the optimum dosage of peanut shell was 5 g / L. The optimum initial concentration of malachite green is 50 mg / L, under this condition, the removal efficiency of malachite green can reach 98.22% within 5 minutes, which is 22.4% higher than that of traditional electroflocculation system. The reaction time was shortened by 55 min, and the removal efficiency was increased by 18.1% compared with the adsorption system of peanut shell alone. Under the optimum current density and the optimum initial concentration of malachite green solution, the ratio of solid to liquid and the time of modification in the electroflocculation modified rice husk system were discussed. The effect of initial pH value of the solution and the amount of modified rice husk on the removal efficiency was obtained. The optimum conditions were as follows: the ratio of solid to liquid was 1: 8, the modification time was 30 min, and the initial pH value of the solution was 8. The dosage of modified rice husk is 3 g / L, under this condition, the removal efficiency of malachite green can reach 97.5, which is 21.7% higher than that of traditional electroflocculation system. The reaction time was shortened by 50 mins, and the removal rate of rice husk modified by NaOH was increased by 17.2% compared with that of the single NaOH modified rice husk adsorption system. The reaction time was shortened by 30 mins. The unit energy consumption and the unit electrode material consumption of different systems were calculated. The unit energy consumption and unit electrode material consumption of the electroflocculation peanut shell adsorption coupling system was 97.4% lower than that of the traditional electroflocculation system. Compared with the traditional electroflocculation system, the adsorption coupling system of NaOH modified rice husk decreased 88.9.The adsorption process of adsorbent was fitted by isotherm model, which showed that peanut shell. The adsorption process of rice husk modified by NaOH accords with Langmuir adsorption isotherm model and Freundlich adsorption isotherm model, and adsorption kinetics accords with quasi second-order kinetic model. The reaction kinetics model of electroflocculation system and coupling system is fitted, which shows that the reaction of the two systems is in good agreement with the second-order kinetic model.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X788

【相似文献】