Preparation and electrochemical characterization of activated carbons by chemical-physical activation

A process was proposed based on the combination of chemical and physical activation for the production of activated carbons used as the electrode material for electric double layer capacitor (EDLC). By material characterization and electrochemical methods, the influences of the activitation process on the specific surface area, pore structure and electrochemical properties of the activated carbons were investigated. The results show that specific surface area, the mesopore volume, and the specific capacitance increase with the increase of the mass ratio of KOH to char (m(KOH)/m(char)) and the activation time, respectively. When m(KOH)/m(char) is 4.0, the specific surface area and the mesopore volume reach the maximum values, i.e. 1 960 m²/g and 0.308 4 cm³/g, and the specific capacitance is 120.7 F/g synchronously. Compared with the chemical activation, the activated carbons prepared by chemical-physical activation show a larger mesopore volume, a higher ratio of mesopore and a larger specific capacitance. Foundation item: Project(2007BAE12B01) supported by the National Key Technology Research and Development Program of China     

Electrochemical performance of interfacially polymerized polyaniline nanofibres as electrode materials for non-aqueous redox supercapacitors

H⁺ doped polyaniline nanofibre (PH) was synthesized by interfacial polymerization and polyanilines doped with Li salt (PLI and PHLI) were prepared by immersing emeraldine base (EB) and H⁺ doped polyaniline in 1 mol/L LiPF₆/(EC-EMC-DMC), respectively. PH, PLI and PHLI were all characterized by scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) spectrometry. With 1 mol/L LiPF₆/(EC-EMC-DMC) as electrolyte, PH, PHLI and PLI were used as the active materials of symmetric non-aqueous redox supercapacitors. PLI shows the highest initial specific capacitance of 120 F/g (47 F/g for PH and 66 F/g for PHLI) among three samples. After 500 cycles, the specific capacitance of PLI remains 75 F/g, indicating the good cycleability.     

Hybrid supercapacitor based on polyaniline doped with lithium salt and activated carbon electrodes

Polyaniline(PANI) nanofiber was synthesized by interfacial polymerization utilizing the interface between HCl and CCl₄. The hybrid type supercapacitors (PLi/C) based on Li-doping polyaniline and activated carbon electrode were fabricated and compared with the redox type capacitors (PLi/PLi) based on two uniformly Li-doping polyaniline electrodes. The electrochemical performances of the two types of supercapacitors were characterized in non-aqueous electrolyte. PLi/C supercapacitors have a wider effective energy storage potential range and a higher upper potential. At the same time, the PLi/C supercapacitor exhibits a specific capacity of 120.93 F/g at initial discharge and retains 80% after 500 cycles. The ohmic internal resistance (R _ES) of PLi/C supercapacitor is 5.0 Ω, which is smaller than that of PLi/PLi capacitor (5.5 Ω). Moreover, it can be seen that Et₄NBF₄ organic solution is more suitable for using as organic electrolyte of PLi/C capacitor compared with organic solution containing LiPF₆. Foundation item: Project(2008AA03Z207) supported by the National High-Tech Research and Development Program of China     

中间相沥青粒径对活性炭材料及其电化学性能的影响

以煤焦油沥青为原料,在500℃下调制得到炭质微晶结构的中间相沥青.以不同粒径的中间相沥青为原料,以KOH和CO2为活化剂,采用物理-化学联合活化法制得超级电容器用高比表面积活性炭.以制备的活性炭作电极材料,以1 mol/L Et4NBF4/PC为有机电解液,考察活性炭材料的电容行为.结果表明:随着中间相沥青粒径的减小,活性炭比表面积先增大后减小;在中间相沥青粒径为150～250 μm时制备的活性炭的BET比表面积达最大值2 476 m2/g,质量比电容量最大,达到103.5 F/g.以粒径75～96 μm中间相沥青制备的活性炭表现出良好的功率特性,在1 mA充放电时,质量比电容量为87 F/g;在20 mA充放电时,质量比电容量也达到83 F/g.     

杂铜阳极泥回转窑氧化焙烧酸浸工艺研究

采用回转窑氧化焙烧—酸浸工艺回收杂铜阳极泥金属铜,研究了不同试验条件对铜浸出率的影响。结果表明:在氧化焙烧温度700℃、焙烧时间20 min、原料粒度-5 mm、空气流量0.5 L/min的条件下,铜浸出率高达97.10%,镍浸出率>90%,大部分铅、锡、锑、铋及贵金属金、银、钯残留在浸出渣中,可以作为后续提取有价金属及贵金属的原料。     

过渡金属盐掺杂聚苯胺材料及电容行为研究

采用化学聚合法制备出盐酸掺杂聚苯胺,去掺杂后分别在ZnCl2丙酮溶液和FeCl3丙酮溶液中再掺杂,制得ZnCl2掺杂聚苯胺材料(PZn)和FeCl3掺杂聚苯胺材料(PFe).用直流电导率仪,扫描电镜(SEM)和红外光谱(FT-IR)对掺杂聚苯胺进行了表征.以1mol/L H2SO4为电解液组装两电极超级电容器,研究了材...     

侧吹熔炼含铁冶炼渣玻璃化研究

为实现危险废物侧吹熔炼含铁冶炼渣的无害化处理,本文采用高温熔融玻璃化技术进行处理,通过掺杂不同质量比例的氧化硅控制碱度,在不同熔融温度、不同冶炼气氛下进行熔融,而后进行水碎。结果表明：随着碱度的下降,熔渣的玻璃态物质占比升高、半球温度明显降低、Fe³⁺/Fe²⁺比例略微下降、黏度上升;同时,当冶炼气氛氧分压下降时,熔渣的玻璃态物质占比和半球温度明显降低,Fe³⁺/Fe²⁺比例均呈下降趋势;1 380～1 420℃区间内,熔炼温度对上述性质影响不太明显;温度升高,玻璃态物质占比、半球温度和黏度略有下降;熔融温度1 400℃时,在CO和CO₂分压比例1∶1、保温时间3 h、碱度0.7的最佳工艺下,用含铁冶炼渣制备出的玻璃体中有害元素的浸出毒性及酸溶失率远低于相关表征限值要求,可以实现无害化处置。