A general research program, focusing on activated carbon fiber cloths （ACFC） and felt for environmental protection was performed. The objectives were multiple： （i） a better understanding of the adsorption mecha- ...A general research program, focusing on activated carbon fiber cloths （ACFC） and felt for environmental protection was performed. The objectives were multiple： （i） a better understanding of the adsorption mecha- nisms of these kinds of materials; （ii） the specification and optimization of new processes using these adsorbents; （iii） the modeling of the adsorption of organic pollutants using both the usual and original approaches; （iv） applications of ACFC in industrial processes. The general question was： how can activated carbon fiber cloths and felts be used in air treatment processes for the protection of environment. In order to provide an answer, different approaches were adopted. The materials （ACFC） were characterized in terms of macro structure and internal porosity. Specific studies were performed to get the air flow pattern through the fabrics. Head loss data were generated and modeled as a fi.mction of air velocity. The performances of ACF to remove volatile organic compounds （VOCs） were approached with the adsorption isotherms and breakthrough curves in various operating conditions. Regenera- tion by Joule effect shows a homogenous heating of adsorber modules with rolled or pleated layers. Examples of industrial developments were presented showing an interesting technology for the removal of VOCs, such as dichloromethane, benzene, isopropyl alcohol and toluene, alone or in a complex mixture.展开更多
In order to investigate the effects of pre-oxidation conditions on adsorption performance of activated carbon fibers （ ACFs ）, electrospun polyacrylonitrile （ PAN ） fiber webs were adopted as precursors for prepar...In order to investigate the effects of pre-oxidation conditions on adsorption performance of activated carbon fibers （ ACFs ）, electrospun polyacrylonitrile （ PAN ） fiber webs were adopted as precursors for preparing ACFs. Firstly, the webs were stabilized under different pre-oxidation conditions; secondly, the pre-oxidative fibers were chemically activated by high temperature treatment in nitrogen. Pre-oxidation temperature, heating rate, and treatment time are the main factors on affecting the adsorption performance of the ACFs. Scanning electron microscope （ SEM）, differential scanning calorimeter （DSC）, and Fourier transform infrared spectroscopy （FTIR） were used to characterize the structure and property of the pre-oxldatlve fibers, and the dynamic benzene adsorption capacity of benzene of ACFs was measured. The results indicate that the moderate pre-oxidation condition is necessary to prepare the ACFs with better adsorption capacity, and the optimal oxidation conditions are to increase from room temperature to 230 ~C with a heating rate of 0.75 ~C ~ min -1 held at the peak temperature for 30min.展开更多
Regenerated activated carbon(RAC)samples were prepared by carbon activation using waste activated carbon from solid waste resources as the carbon source precursor coupled with adding alkaline additives,and then were f...Regenerated activated carbon(RAC)samples were prepared by carbon activation using waste activated carbon from solid waste resources as the carbon source precursor coupled with adding alkaline additives,and then were further modified by potassium ferrate to finally prepare high-performance carbon for VOCs adsorption.At the same time,the samples before and after modification were systematically studied through characterization techniques such as SEM,Raman spectrometry,FT-IR,XPS,and dynamic/static adsorption.The results showed that the specific surface area and pore volume of the RAC after modification by the strong oxidant potassium ferrate increased by 1.4 times;the degree of defects was enhanced and the content of oxygen-containing functional groups on the surface increased significantly.Among them,the sample modified with potassium ferrate for 24 h had the best dynamic toluene adsorption performance(375.5 mg/g),and the dynamic adsorption capacity was twice that of the original sample(192.8 mg/g).The static adsorption test found that the maximum adsorption capacity of RAC-6%K_(2)FeO_(4)+H_(2)SO_(4)-24h was 796 mg/g,which indicated that the potassium ferrate modification treatment could significantly increase the VOCs adsorption performance of RAC.In addition,through consecutive toluene adsorption-desorption cycle tests,it was found that the RAC-6%K_(2)FeO_(4)+H_(2)SO_(4)-24h sample still retained 91%of adsorption activity after the fifth regeneration cycle.This indicates that RAC-6%K_(2)FeO_(4)+H_(2)SO_(4)-24h has good cycle stability and great application value for the efficient purification of industrial waste VOCs gas.展开更多
TiO2-loaded activated carbon fibers （ACF） were prepared by a hydrothermal method. The samples were characterized by scanning electron microscopy （SEM）, X-ray diffraction （XRD）, Fourier transform infrared （FTIR...TiO2-loaded activated carbon fibers （ACF） were prepared by a hydrothermal method. The samples were characterized by scanning electron microscopy （SEM）, X-ray diffraction （XRD）, Fourier transform infrared （FTIR） spectrometry and UV-vis diffuse reflectance spectra （DRS）. SEM images showed that the TiO2 nanoparticles were deposited on the surface of ACF, and the particle size and loading amount of TiO2 were varied by changing the initial concentration of tetrabutyl titanate （TBOT）. The results of an ash experiment showed that the loading amounts of TiO2 were 18.4%, 43.3%, 52.5%, 75.1%, and 91.1% for initial concentrations of TBOT of 0.07,014, 0.21,0.28, and 0.35 tool/L, respectively, Physical interactions played an important role in the formation of TiO2/ACF composite fibers that absorb UV and visible light. Compared with those of ACF, improved adsorption and photocatalytic activity toward Rhodamine B （RhB） were observed for TiO2/ACF composite fiber. The Rhodamine B could be removed efficiently by TiO2/ACF composite fibers, and the TiO2 loading amount had a significant effect on the photocatalytic activity of TiO2/ACF composite fibers.展开更多
Fractal pore-size distribution K(x) is given based on J(x) function proposed by Jaronic. Activated carbon fibers (ACF) with different surface areas are characterized by using two functions mentioned above. The present...Fractal pore-size distribution K(x) is given based on J(x) function proposed by Jaronic. Activated carbon fibers (ACF) with different surface areas are characterized by using two functions mentioned above. The present work studies the fractal pore-size distribution of ACF and adsorption isotherms of nonpolar benzene vapor on ACF, and thereby reveals the correlation between them.展开更多
对室内甲醛的来源和污染现状进行了初步分析,指出甲醛严重危害人类健康。分别用HNO_3、NH_3—NH_4Cl、H_2O_2对活性炭纤维进行表面改性,动态吸附试验发现用H_2O_2改性后对甲醛的吸附效果最佳,并用日立(HITACHI)X-650型扫描电子显微镜(SE...对室内甲醛的来源和污染现状进行了初步分析,指出甲醛严重危害人类健康。分别用HNO_3、NH_3—NH_4Cl、H_2O_2对活性炭纤维进行表面改性,动态吸附试验发现用H_2O_2改性后对甲醛的吸附效果最佳,并用日立(HITACHI)X-650型扫描电子显微镜(SEM,Scanning Electron Microscope)进行了显微结构分析。结果表明活性炭纤维特别是改性活性炭纤维治理含甲醛的空气具有良好的应用前景。展开更多
文摘A general research program, focusing on activated carbon fiber cloths （ACFC） and felt for environmental protection was performed. The objectives were multiple： （i） a better understanding of the adsorption mecha- nisms of these kinds of materials; （ii） the specification and optimization of new processes using these adsorbents; （iii） the modeling of the adsorption of organic pollutants using both the usual and original approaches; （iv） applications of ACFC in industrial processes. The general question was： how can activated carbon fiber cloths and felts be used in air treatment processes for the protection of environment. In order to provide an answer, different approaches were adopted. The materials （ACFC） were characterized in terms of macro structure and internal porosity. Specific studies were performed to get the air flow pattern through the fabrics. Head loss data were generated and modeled as a fi.mction of air velocity. The performances of ACF to remove volatile organic compounds （VOCs） were approached with the adsorption isotherms and breakthrough curves in various operating conditions. Regenera- tion by Joule effect shows a homogenous heating of adsorber modules with rolled or pleated layers. Examples of industrial developments were presented showing an interesting technology for the removal of VOCs, such as dichloromethane, benzene, isopropyl alcohol and toluene, alone or in a complex mixture.
文摘In order to investigate the effects of pre-oxidation conditions on adsorption performance of activated carbon fibers （ ACFs ）, electrospun polyacrylonitrile （ PAN ） fiber webs were adopted as precursors for preparing ACFs. Firstly, the webs were stabilized under different pre-oxidation conditions; secondly, the pre-oxidative fibers were chemically activated by high temperature treatment in nitrogen. Pre-oxidation temperature, heating rate, and treatment time are the main factors on affecting the adsorption performance of the ACFs. Scanning electron microscope （ SEM）, differential scanning calorimeter （DSC）, and Fourier transform infrared spectroscopy （FTIR） were used to characterize the structure and property of the pre-oxldatlve fibers, and the dynamic benzene adsorption capacity of benzene of ACFs was measured. The results indicate that the moderate pre-oxidation condition is necessary to prepare the ACFs with better adsorption capacity, and the optimal oxidation conditions are to increase from room temperature to 230 ~C with a heating rate of 0.75 ~C ~ min -1 held at the peak temperature for 30min.
基金financialy supported by the National Natural Science Foundation of China (No.21936005,52070114,21876093)the Postdoctoral Science Program of China (No.2019M660061)
文摘Regenerated activated carbon(RAC)samples were prepared by carbon activation using waste activated carbon from solid waste resources as the carbon source precursor coupled with adding alkaline additives,and then were further modified by potassium ferrate to finally prepare high-performance carbon for VOCs adsorption.At the same time,the samples before and after modification were systematically studied through characterization techniques such as SEM,Raman spectrometry,FT-IR,XPS,and dynamic/static adsorption.The results showed that the specific surface area and pore volume of the RAC after modification by the strong oxidant potassium ferrate increased by 1.4 times;the degree of defects was enhanced and the content of oxygen-containing functional groups on the surface increased significantly.Among them,the sample modified with potassium ferrate for 24 h had the best dynamic toluene adsorption performance(375.5 mg/g),and the dynamic adsorption capacity was twice that of the original sample(192.8 mg/g).The static adsorption test found that the maximum adsorption capacity of RAC-6%K_(2)FeO_(4)+H_(2)SO_(4)-24h was 796 mg/g,which indicated that the potassium ferrate modification treatment could significantly increase the VOCs adsorption performance of RAC.In addition,through consecutive toluene adsorption-desorption cycle tests,it was found that the RAC-6%K_(2)FeO_(4)+H_(2)SO_(4)-24h sample still retained 91%of adsorption activity after the fifth regeneration cycle.This indicates that RAC-6%K_(2)FeO_(4)+H_(2)SO_(4)-24h has good cycle stability and great application value for the efficient purification of industrial waste VOCs gas.
基金financial support of the National Natural Science Foundation of China(No.21103017No.51104042)the Fundamental Research Funds for the Central Universities(No.110405007)
文摘TiO2-loaded activated carbon fibers （ACF） were prepared by a hydrothermal method. The samples were characterized by scanning electron microscopy （SEM）, X-ray diffraction （XRD）, Fourier transform infrared （FTIR） spectrometry and UV-vis diffuse reflectance spectra （DRS）. SEM images showed that the TiO2 nanoparticles were deposited on the surface of ACF, and the particle size and loading amount of TiO2 were varied by changing the initial concentration of tetrabutyl titanate （TBOT）. The results of an ash experiment showed that the loading amounts of TiO2 were 18.4%, 43.3%, 52.5%, 75.1%, and 91.1% for initial concentrations of TBOT of 0.07,014, 0.21,0.28, and 0.35 tool/L, respectively, Physical interactions played an important role in the formation of TiO2/ACF composite fibers that absorb UV and visible light. Compared with those of ACF, improved adsorption and photocatalytic activity toward Rhodamine B （RhB） were observed for TiO2/ACF composite fiber. The Rhodamine B could be removed efficiently by TiO2/ACF composite fibers, and the TiO2 loading amount had a significant effect on the photocatalytic activity of TiO2/ACF composite fibers.
文摘Fractal pore-size distribution K(x) is given based on J(x) function proposed by Jaronic. Activated carbon fibers (ACF) with different surface areas are characterized by using two functions mentioned above. The present work studies the fractal pore-size distribution of ACF and adsorption isotherms of nonpolar benzene vapor on ACF, and thereby reveals the correlation between them.
文摘对室内甲醛的来源和污染现状进行了初步分析,指出甲醛严重危害人类健康。分别用HNO_3、NH_3—NH_4Cl、H_2O_2对活性炭纤维进行表面改性,动态吸附试验发现用H_2O_2改性后对甲醛的吸附效果最佳,并用日立(HITACHI)X-650型扫描电子显微镜(SEM,Scanning Electron Microscope)进行了显微结构分析。结果表明活性炭纤维特别是改性活性炭纤维治理含甲醛的空气具有良好的应用前景。
