磁性多壁碳納米管吸附去除水中Cu（Ⅱ）和亞甲基藍的研究
發(fā)布時間：2018-07-29 10:48
【摘要】：在實際環(huán)境中有機物-重金屬復合污染非常普遍,是構(gòu)成環(huán)境污染重要的來源。而工業(yè)生產(chǎn)廢水組成復雜多變,重金屬銅和有機物亞甲基藍同時存在的可能性很大。目前常用的處理廢水的方法都有不同的局限性,而吸附法是一種重要的物理化學方法,在處理廢水中有機物和無機物污染廢水中有著廣泛的應用。隨著碳納米管及納米材料研究的深入其廣闊的應用前景也不斷地展現(xiàn)出來,研究者們研究了其對水中有機物和無機物的吸附,展現(xiàn)其比表面積大、粒徑小、吸附容量大的優(yōu)點。但吸附過后很難分離,排入水體不僅造成資源浪費而且廣泛存在于環(huán)境中的碳納米管的環(huán)境風險也應當被關(guān)注。近幾年來,磁分離作為物理處理技術(shù)在水處理中獲得了許多成功應用,顯示出其高效、快速、經(jīng)濟等許多優(yōu)點。本課題將磁分離技術(shù)應用于多壁碳納米管的吸附,采用化學共沉淀的方法制備了磁性多壁碳納米管(MMWCNT),測定了吸附劑的磁穩(wěn)定性,用掃描電鏡(SEM)、BET比表面積(SSA)、Zeta電位儀、X射線光電子能譜(XPS)對磁性多壁碳納米管復合物進行了表征。研究了亞甲基藍和銅在MMWCNT上的單一和競爭吸附�？疾炝艘辉w系中吸附動力學、吸附熱力學及pH值對吸附性能的影響。進一步探究了吸附劑在河水水樣中的效果,吸附劑回收率及循環(huán)利用的能力以及二元體系中亞甲基藍和銅之間的競爭吸附現(xiàn)象。結(jié)果表明,鐵氧化物納米顆粒成功地覆蓋在多壁碳納米管表面,形成的MMWCNT易于磁性分離；MMWCNT的比表面積為139.86 m2/g；等電點為5.3。一元體系中,在4h時內(nèi)對亞甲基藍和銅的吸附達到平衡,吸附過程符合準二級動力學模型,等溫吸附數(shù)據(jù)符合Langmuir模型,最大吸附量分別為46.03mg/g和27.74mg/g;pH值是影響吸附效果的重要因素；而且MMWCNT在環(huán)境水樣中的吸附效果明顯提高；MMWCNT具有較高的回收率,五次解吸循環(huán)實驗后,MMWCNT對MB的平衡吸附量從45.5 mg/g降到34.2 mg/g,對于Cu(II)的平衡吸附量仍有17.6 mg/g,表明吸附性能仍然良好,MMWCNT有望運用于實際水處理中。競爭吸附過程中亞甲基藍優(yōu)先吸附,對Cu(II)的吸附有一定的抑制作用,當亞甲基藍吸附平衡后,隨著吸附劑量的增加銅的吸附效率從11.03%增到73%。
[Abstract]:Organic-heavy metal compound pollution is very common in the real environment, and it is an important source of environmental pollution. However, the composition of industrial wastewater is complex and changeable, and it is very likely that heavy metal copper and organic methylene blue exist at the same time. At present, the common methods of wastewater treatment have different limitations, and adsorption is an important physical and chemical method, which is widely used in the treatment of organic and inorganic pollutants in wastewater. With the further study of carbon nanotubes and nano-materials, their broad application prospects have been continuously demonstrated. Researchers have studied the adsorption of organic and inorganic compounds in water, showing the advantages of large specific surface area, small particle size and large adsorption capacity. However, it is difficult to separate after adsorption, and the environmental risk of carbon nanotubes (CNTs) which exist widely in the environment should also be paid attention to. In recent years, as a physical treatment technology, magnetic separation has been successfully applied in water treatment, showing its many advantages, such as high efficiency, fast and economical. In this paper, the magnetic separation technology was applied to the adsorption of multi-walled carbon nanotubes, and the magnetic stability of the adsorbent was determined by chemical coprecipitation method. The magnetic multiwalled carbon nanotubes (MCNTs) composites were characterized by scanning electron microscope (SEM) (SEM) BET specific surface area (SSA) / Zeta potentiometer and X-ray photoelectron spectroscopy (XPS). The single and competitive adsorption of methylene blue and copper on MMWCNT was studied. The effects of adsorption kinetics, adsorption thermodynamics and pH value on adsorption properties were investigated. The effect of adsorbent in river water, the recovery rate and recycling ability of adsorbent and the competitive adsorption between methylene blue and copper in binary system were investigated. The results show that the iron oxide nanoparticles are successfully covered on the surface of multi-walled carbon nanotubes, and the specific surface area and isoelectric point of MMWCNT are 139.86 m2 / g and 5.3, respectively. The adsorption of methylene blue and copper reached equilibrium within 4 hours, the adsorption process was in accordance with the quasi-second-order kinetic model, and the isothermal adsorption data was in accordance with Langmuir model. The maximum adsorption capacity of 46.03mg/g and pH value of 27.74 mg / g 路g / g were the important factors affecting the adsorption effect. Moreover, the adsorption efficiency of MMWCNT in environmental water samples was significantly improved, and the recovery rate of MMWCNT was higher. After five desorption cycles, the equilibrium adsorption capacity of MMWCNT to MB decreased from 45.5 mg/g to 34.2 mg / g, and the equilibrium adsorption capacity to Cu (II) was still 17.6 mg / g, indicating that the adsorption performance of MMWCNT is still good. Methylene blue preferentially adsorbed methylene blue and inhibited the adsorption of Cu (II). When methylene blue adsorbed equilibrium the adsorption efficiency of copper increased from 11.03% to 73% with the increase of adsorption dose.
【學位授予單位】：湖南大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：X788
[Abstract]:Organic-heavy metal compound pollution is very common in the real environment, and it is an important source of environmental pollution. However, the composition of industrial wastewater is complex and changeable, and it is very likely that heavy metal copper and organic methylene blue exist at the same time. At present, the common methods of wastewater treatment have different limitations, and adsorption is an important physical and chemical method, which is widely used in the treatment of organic and inorganic pollutants in wastewater. With the further study of carbon nanotubes and nano-materials, their broad application prospects have been continuously demonstrated. Researchers have studied the adsorption of organic and inorganic compounds in water, showing the advantages of large specific surface area, small particle size and large adsorption capacity. However, it is difficult to separate after adsorption, and the environmental risk of carbon nanotubes (CNTs) which exist widely in the environment should also be paid attention to. In recent years, as a physical treatment technology, magnetic separation has been successfully applied in water treatment, showing its many advantages, such as high efficiency, fast and economical. In this paper, the magnetic separation technology was applied to the adsorption of multi-walled carbon nanotubes, and the magnetic stability of the adsorbent was determined by chemical coprecipitation method. The magnetic multiwalled carbon nanotubes (MCNTs) composites were characterized by scanning electron microscope (SEM) (SEM) BET specific surface area (SSA) / Zeta potentiometer and X-ray photoelectron spectroscopy (XPS). The single and competitive adsorption of methylene blue and copper on MMWCNT was studied. The effects of adsorption kinetics, adsorption thermodynamics and pH value on adsorption properties were investigated. The effect of adsorbent in river water, the recovery rate and recycling ability of adsorbent and the competitive adsorption between methylene blue and copper in binary system were investigated. The results show that the iron oxide nanoparticles are successfully covered on the surface of multi-walled carbon nanotubes, and the specific surface area and isoelectric point of MMWCNT are 139.86 m2 / g and 5.3, respectively. The adsorption of methylene blue and copper reached equilibrium within 4 hours, the adsorption process was in accordance with the quasi-second-order kinetic model, and the isothermal adsorption data was in accordance with Langmuir model. The maximum adsorption capacity of 46.03mg/g and pH value of 27.74 mg / g 路g / g were the important factors affecting the adsorption effect. Moreover, the adsorption efficiency of MMWCNT in environmental water samples was significantly improved, and the recovery rate of MMWCNT was higher. After five desorption cycles, the equilibrium adsorption capacity of MMWCNT to MB decreased from 45.5 mg/g to 34.2 mg / g, and the equilibrium adsorption capacity to Cu (II) was still 17.6 mg / g, indicating that the adsorption performance of MMWCNT is still good. Methylene blue preferentially adsorbed methylene blue and inhibited the adsorption of Cu (II). When methylene blue adsorbed equilibrium the adsorption efficiency of copper increased from 11.03% to 73% with the increase of adsorption dose.
【學位授予單位】：湖南大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：X788
【參考文獻】
相關(guān)期刊論文 前10條
1 莫冰玉;唐玉斌;陳芳艷;溫濤;;磁性活性炭的制備及其對水中甲基橙的吸附[J];環(huán)境工程學報;2015年04期
2 趙慶松;王艷旗;代彥;黃艷鳳;李穎;張紀梅;;新型微/納米材料在染料污染吸附去除上的應用[J];天津工業(yè)大學學報;2013年05期
3 張秀蓉;龔繼來;曾光明;鄧久華;;磁性氧化石墨烯制備及去除水中剛果紅的研究[J];中國環(huán)境科學;2013年08期
4 張佳;任秉雄;王鵬;王崇臣;;山茶籽粉吸附亞甲基藍的性能研究[J];環(huán)境化學;2013年08期
5 劉亞納;湯紅妍;朱書法;周鳴;苗娟;;花生殼活性炭對亞甲基藍的吸附特性[J];環(huán)境工程學報;2013年08期
6 徐龍君;劉科;張福凱;;磁性活性炭處理含銅廢水[J];環(huán)境工程學報;2012年09期
7 周鋒;萬欣;傅迎慶;;氧化石墨還原法制備石墨烯及其吸附性能[J];深圳大學學報(理工版);2011年05期
8 張q，
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