煤基活性炭比表面积表征研究

为了建立适用于不同类型及孔结构煤基活性炭比表面积的科学计算方法,用物理吸附分析法对宁夏煤基活性炭比表面进行表征,通过研究Langmuir比表面积和BET比表面积理论模型,探讨了两种比表面积表征结果的特点和原因．结果表明,同一材料的Langmuir比表面积大于BET比表面积,本质上是由于依据Langmuir方程得到的单层吸附量大于依据BET理论所求得的单层吸附量．     

超大容量双电层电容器的研制

双电层电容器是一种功率密度高和能量密度大的新型储能元件。研究以活性炭为材料的双电层电容器的制作，对制作压力、活性物质涂载量及电解液浓度进行了研究，摸索出电容器的制作工艺。实验过程中采用循环伏安、交流阻抗和恒电流充放电方法对电极和电容器进行性能测试。结论是活性炭电极在制作压力为20MPa，活性物质涂载量为30mg／cm^2，电解液为7moL／L的KOH水溶液时性能最优。实验单体小电容器的比容量可达54．01F／g，并研制出容量高达1247．32F的超大容量电容器。     

基于碳纳米管的双电层电容器

碳纳米管由于具有良好的导电性、较高的比表面积、优良的化学稳定性。因而被认为是超级电容器的理想电极材料，本文制备了基于碳纳米管的双电层电容器，其比容量为21F/g，等效电阻为2Ω，漏电流为1.5mA，同活性炭相比，碳纳米管电极因为独特的孔隙结构而具有高的比表面积利用率和低的等效电阻，在高功率大容量电容器方面有着广阔的应用前景。     

含油污泥制备高比表面积活性炭

以含油污泥为原料,氢氧化钠为活化剂,在氮气保护下,通过室内静态热解炉制备高比表面积活性炭。研究炭化温度、活化升温方式、活化温度、活化时间和碱碳质量比m(NaOH)／m(C)对高比表面活性炭的影响。采用全自动比表面与孔隙度分析仪、钨灯丝环境扫描电子显微镜等测试设备,分别对产品的比表面积与孔径分布、组成及微观形貌进行定性或定量分析。研究结果表明,含油污泥制备高比表面积活性炭的较佳条件为:炭化温度500℃,活化升温方式(c),活化温度800℃,活化时间1h, m(NaOH)／m(C)=2。采用本方法制备的活性炭比表面积大于2000m2/g,平均孔径小于2nm,总孔容大于2cm3/g,性能优于普通活性炭,可作为能源储存介质、电极材料、高效吸附剂的基础材料,为含油污泥的资源化利用提供了一条新途径。     

负载贵金属的层柱分子筛比表面积研究

采用两种矿产钙质蒙脱土为原料制备了两种层柱分子筛（Ａｌ－ＣＬＭ和Ａｌ－ＣＬＢ）。首先考察了焙烧温度对其比表面积的影响，结果发现在３００～５００℃范围内，随着焙烧温度的提高，层柱分子筛的比表面积逐渐增大，６００℃以后比表面积迅速下降；对负载贵金属Ｐｔ或Ｐｄ后其比表面积变化情况的研究表明，不论是Ａｌ－ＣＬＭ还是Ａｌ－ＣＬＢ，负载金属后比表面积均下降，且负载Ｐｔ后比表面积下降均比负载Ｐｄ后比表面积下降得多；在Ｐｔ／Ａｌ－ＣＬＭ比表面积因浸渍液的不同而引起的比表面积变化的研究中，发现用酸性较强的浸渍液（Ｈ２ＰｔＣｌ６·６Ｈ２Ｏ）比用酸性较弱的浸渍液（Ｐｔ（ＮＨ３）４Ｃｌ２）所引起的比表面积下降得多，最后在Ｐｔ（Ｐｄ）／Ａｌ－ＣＬＭ和Ｐｔ（Ｐｄ）／Ａｌ－ＣＬＢ的苯加氢反应中发现苯转化率随着比表面积的增大而上升。     

负载贵金属的层柱分子筛比表面积研究

采用两种矿产钙质蒙脱土为原料制备了两种层柱分子筛。首先考察了焙烧温度对其比表面积的影响。结果发现在３００－５００℃范围内，随着焙烧或Ｐｄ后比表面变化情况的研究表明，不论是Ａｌ－ＣＬＭ还是Ａｌ－ＣＬＢ，负载金属后比表面积均下降，且负载Ｐｔ后比表面积下降均比负载Ｐ ｄ后比表面积下降得多；在Ｐｔ／Ａｌ－ＣＬＭ比表面积因当渍液的不同而引起的比表面积变化的研究中，发现用酸性较强的浸渍液比用酸性较弱的浸渍注所     

高比表面积活性炭纤维毡的制备及性能表征

以聚丙烯腈为原料，经过大量的实验研究，制备出了性能优异的高比表面积活性炭纤维毡，试验制得的活性炭纤维毡的碘吸附值达到1700mg／g左右、苯吸附量达到90％左右、比表面积约为1800m^2／g．     

石油焦制备高比表面积活性炭技术的研究

研究了以石油焦为原料、KOH化学活化法制备高比表面积活性炭工业化技术,以及工业化制备中碱炭比、活化温度、活化时间对产品指标的影响,提出了适合高比表面积活性炭工业化的新型反应器及碱液回收处理工艺,确定了生产高比表面积活性炭的最佳工艺条件：碱炭比5、活化温度830℃、活化时间1．0h．结果表明,采用确定的技术路线可实现高比表面积活性炭的工业化,采用确定的工艺条件可工业化制备BET比表面积达2900m^2/g、平均孔径2．46nm的活性炭产品。     

基于PSIM的双电层电容器仿真器的研究

文章提出了一种用电解电容和三相变换电路构成的双电层电容器仿真器模型,阐述和分析了该仿真器模型的工作原理,并在PSIM6.0环境下对仿真器模型进行了计算机仿真,仿真结果验证了所提出的仿真器模型的正确性,它能够用小容量的电解电容有效地模拟大容量的双电层电容器。     

基于PSIM的双电层电容器仿真器的研究

文章提出了一种用电解电容和三相变换电路构成的双电层电容器仿真器模型,阐述和分析了该仿真器模型的工作原理,并在PSIM6.0环境下对仿真器模型进行了计算机仿真,仿真结果验证了所提出的仿真器模型的正确性,它能够用小容量的电解电容有效地模拟大容量的双电层电容器.     

Adsorption of K+ from an aqueous phase onto an activated carbon used as an electric double-layer capacitor electrode

The adsorption capacity and absorption rate for electrolyte onto activated carbon are important parameters used to characterize activated carbon electric double-layer capacitor electrodes. In this paper the pore structure of typical commercial activated carbons, and various Mn-doped activated carbons prepared on a laboratory scale, are described. The pore structure was characterized by N2 adsorption/desorption isotherms. Isotherms for K+ adsorption onto these activated carbons from the aqueous phase were also obtained. The experimental, equilibrium K+ adsorption data were fitted to the Langmuir, Freundlich or Temkin equations. Adsorption of K+ onto the activated carbons was measured and plotted as a function of time. The adsorption kinetic data were modeled by either pseudo-first or pseudo-second order equations. The Elvoich equation, a liquid film diffusion and an intra-particle diffusion model were used to fit the kinetic data. The results indicate that the adsorption of K+ onto activated carbon is influenced by many factors including pore size distribution, specific surface area and the surface chemistry of the activated carbons. The Temkin equation best describes the equilibrium adsorption data. The pseudo-second order model exactly describes the whole adsorption process, which is controlled by both liquid film and intra-particle diffusion.     

Optimal electrochemical performances of CO2 activated carbon aerogels for supercapacitors

Activated carbon aerogels（ACAs） derived from sol-gel polycondensation of resorcinol （R） and formaldehyde （F） were pyrolyzed under Ar flow and activated in CO2 atmosphere. The morphology of ACAs was characterized by scanning electron microscopy （SEM） and the structural properties were determined by N2 adsorption at 77 K. The results show that ACAs have a typical three-dimensional nanonetwork structure composing of cross-linking of carbon nanoparticles. The specific surface area and the total pore volume remarkably increase with increasing activation time while the previous porous structure still remains. The specific capacitance of the 950-10-ACA electrode can reach up to 212.3 F/g in 6 mol/L KOH electrolyte. The results of constant-current charge-discharge testing indicate that the ACAs electrodes present fast charge- discharge rate and long cycle life （about 98% capacitance retained after 3000 charge-discharge cycles at 1.25 mA/cm2）. Lower internal resistances can be achieved for 950-10-ACA electrode in KOH electrolyte. Our investigations are very important to improve the wettability and electrochemical performance of electrode for supercapacitors.     

碳基凝胶聚合物电解质双电层电容器的研究

为了克服液体电解液电容器的漏液和安全问题,以活性炭作电极材料,丙烯腈作聚合物单体,分别以碳酸丙烯酯 碳酸乙烯酯、碳酸二甲酯 碳酸乙烯酯和碳酸甲乙酯 碳酸乙烯酯的混合液作增塑剂,高氯酸锂为支持电解质盐,采用内聚合法制备了PAN基凝胶聚合物电解质双电层电容器(GPE-EDLCs).采用交流阻抗法测量了凝胶聚合物电解质(GPE)的离子电导率.采用交流阻抗、循环伏安、恒流充放电等测试方法研究了GPE-EDLCs的性能,并与有机电解液双电层电容器(LOE-EDLCs)进行了比较.结果表明,PAN基GPE的电导率在室温下为6.51～8.94 mS·cm-1,PAN基GPE-EDLCs的工作电压为2.5 V,电容器的比容量为43.9～47.4F/g(i=0.5 mA/cm2),能量密度为128.8～148.1 J/g,与LOE-EDLCs性质相近.     

Influence of nitrogen hetero-substitution on the electrochemical performance of coal-based activated carbons measured in non-aqueous electrolyte

Nitrogen-containing carbons were prepared by modification of activated carbons. The modified carbons were used as electrode materials with improved electrochemical performance. Precursor anthracite was activated by KOH (KOH: anthracite= 1:1), modified by melamine or urea and then treated at 1173 K to obtain the modified carbons. The porous structure, the chemical composition and the electrochemical characteristics of the carbons were investigated by nitrogen sorption, XPS and electrochemical methods respectively. Electrochemical experiments were performed in an organic electrolytic solution of 1 M (C2H5)4NBF4/PC.The samples modified by the different methods showed differences in chemical composition that introduced varying degrees of electrochemical performance enhancement. The presence of nitrogen enhanced the electron donor properties and the surface wettability of the activated carbons: this ensured a sufficient utilization of the exposed surface for charge storage.     

Influence of polyethylene glycol on pore structure and electric double-layer capacitance of carbon xerogel

Mesoporous polyethylene glycol-resorcinol and formaldehyde(PEG-RF) carbon xerogels were prepared by a new polymer blend method in which PEG-RF mixed organic xerogels were synthesized by blending thermally unstable polyethylene glycol with organic monomers, resorcinol and formaldehyde and then subjected to pyrolization at 1 000℃. The influences of mass ratio of PEG to the theoretical yield of RF xerogel, m(PEG)/m(RF) and the relative molecular mass of PEG on the pore structure and electric double layer capacitance(EDLC) performance of PEG-RF carbon xerogels were investigated. The results show that PEG under different conditions leads to the difference of phase separation structure of the polymer blend and thus the change of pore structure of PEG-RF carbon xerogels. Specific surface area and capacity of PEG-RF carbon xerogels in 300/60 H2SO4 solution can reach 755 m^2/g and 150 F/g, respectively. Their surface can be fully utilized to form electric double layer. However, the pore structure differences of PEG-RF carbon xerogels result in their different EDLC performances. The distributed capacitance effect increases with decreasing the pore size of PEG-RF carbon xerogels.     

重铬酸钾溶液预处理及活化对炭纤维比表面积的影响

炭纤维在活化前比表面积小于2m^2／g，通过适当的活化方法可以不同程度提高炭纤维的比表面积．以PAN基炭纤维为原料，用K2Cr2O7溶液进行预处理，再用水蒸汽进行活化．通过考察预处理时间、K2Cr207溶液的浓度、活化时间，得到在10％K2Cr2O7溶液预处理0．5h、再水蒸汽活化2h的条件下，炭纤维的比表面积可达1023m^2／g．