以玻璃炭球为原料,采用在干燥空气流中500℃高温热处理3 h(第一步活化处理),而后在415℃低温处理不同时间(第二步活化处理)的两步活化法制取了一系列活性炭球.依据77 K N2吸/脱附等温线,应用BET、αs-plot和BJH法测定了所得活性炭球的孔结构.结果表明:第一步活化处理后,在炭球表面生成少量大孔(中孔甚至大孔),这些大孔是第二步活化时活化气体(空气)的扩散入口,使得第二步活化处理时微孔的生成量增加.由此可以认为这种二步活化法是获得高收率的较高比面积和微孔容积活性炭的一种有效途径.
A series of activated carbons was prepared using a two-step activation process. The starting glass-like carbon spheres were heated at 500 ℃ for 3 h ( first step activation), and then at a low temperature, below 415 ℃, for different times ( second step activation), in a flow of dry air. Their pore structures were evaluated from N2 gas adsorption/desorption isotherms at 77 K by BET, αs-plot and BJH methods. The first step of activation generated a few large pores ( mesopores and even macropores), on the surface of the spheres, which formed the entrance for the activating reagent gas( air), to increase micropores at a low temperature in the second step of activation. This two-step activation process was found to be an efficient approach to get a comparatively high surface area and a volume of micropores with a high activation yield.
参考文献
| [1] | Sanada Y;Suzuki M;Fujimoto K.Activated Carbons Fundamentals and Applications[M].Koudansha,1992 |
| [2] | Mays T J.Active carbon fibers[A].Pergamon,Amsterdam,1999:95-118. |
| [3] | Elzbieta Frackowiak;Francois Beguin .Carbon materials for the electrochemical storage of energy in capacitors[J].Carbon: An International Journal Sponsored by the American Carbon Society,2001(6):937-950. |
| [4] | Derbyshire F;Jagtoyen M;Thwaites M.Activated carbons-production and application[A].Edward Arnold,1995:227-252. |
| [5] | Inagaki M;Tascon J M D.Pore formation and control in carbon materials[A].Amsterdam:Elsevier,2006:49-105. |
| [6] | Marsh H;Yan D S;O'Grady T M et al.Formation of active carbons from cokes using potassium hydroxide[J].Carbon,1984,22:603-611. |
| [7] | Kyotani T.Porous carbons[A].Amsterdam:Elsevier,2003:109-127. |
| [8] | Zhi-Guo Shi;Yu-Qi Feng;Li Xu .Preparation of porous carbon-silica composite monoliths[J].Carbon: An International Journal Sponsored by the American Carbon Society,2003(13):2668-2670. |
| [9] | Miyake T.;Hanaya M. .Carbon-coated material with bimodal pore-size distribution[J].Journal of Materials Science,2002(5):907-910. |
| [10] | Shiraishi S;Kurihara H;Tsubota H et al.Electric double layer capacitance of highly porous carbon derived from lithium metal and polytetra-fluoroethylene[J].Electrochemical and Solid-State Letters,2001,4:A5-A8. |
| [11] | Osamu Tanaike;Hiroaki Hatori;Yoshio Yamada .Preparation and pore control of highly mesoporous carbon from defluorinated PTFE[J].Carbon: An International Journal Sponsored by the American Carbon Society,2003(9):1759-1764. |
| [12] | Hanzawa Y;Kaneko K;Yoshizawa N et al.The pore structure determination of carbon aerogels[J].ADSORPTION-JOURNAL OF THE INTERNATIONAL ADSORPTION SOCIETY,1998,4:187-195. |
| [13] | Tamon H.;Mikami M.;Okazaki M.;Ishizaka H. .POROUS STRUCTURE OF ORGANIC AND CARBON AEROGELS SYNTHESIZED BY SOL-GEL POLYCONDENSATION OF RESORCINOL WITH FORMALDEHYDE[J].Carbon: An International Journal Sponsored by the American Carbon Society,1997(6):791-796. |
| [14] | Yamamoto T;Nishimura T;Suzuki T et al.Effect of drying method on mesoprosity of resorcinol-formaldehyde drygel and carbon gel[J].Drying Tech,2001,19:1319-1333. |
| [15] | Michio Inagaki;Katsumi Kaneko;Takashi Nishizawa .Nanocarbons-recent research in Japan[J].Carbon: An International Journal Sponsored by the American Carbon Society,2004(8/9):1401-1417. |
| [16] | M. Inagaki;S. Kobayashi;F. Kojin .Pore structure of carbons coated on ceramic particles[J].Carbon: An International Journal Sponsored by the American Carbon Society,2004(15):3153-3158. |
| [17] | Morishita T;Suzuki T;Nishikara T.Preparation of porous carbons by the carboinization of the mixtures of the thermoplastic precursors with MgO[J].Tanso,2005(219):226-231. |
| [18] | Moriashita T;Suzuki T;Nishikawa T.Preparation of mesoporous carbons by carbonization of the mixtures of poly(vinyl alcohol) with magnesium salts[J].Tanso,2006(223):220-226. |
| [19] | T. Morishita;Y. Soneda;T. Tsumura .Preparation of porous carbons from thermoplastic precursors and their performance for electric double layer capacitors[J].Carbon: An International Journal Sponsored by the American Carbon Society,2006(12):2360-2367. |
| [20] | Takahiro Morishita;Kaori Ishihara;Masaya Kat .Preparation of a carbon with a 2 nm pore size and of a carbon with a bi-modal pore size distribution[J].Carbon: An International Journal Sponsored by the American Carbon Society,2007(1):209-211. |
| [21] | Morishita T;Ishihara K;Karo M.Mesoporous carbons prepared from mixtures of magnesium citrate with poly (vinyl alcohol)[J].Tanso,2007(226):19-24. |
| [22] | Inagaki M;Suwa T .Nano-structure control in carbon spheres by air oxidation-derivation of master curves[J].Molecular Crystals and Liquid Crystals,2002,386:197-203. |
| [23] | Nishikawa T;Inagaki M .Air oxidation of carbon spheres. I. Master curves of pore parameters[J].Adsorption Science & Technology,2005(10):827-837. |
| [24] | Inagaki M;Nishikawa T;Oshida K et al.Air oxidation of carbon spheres Ⅱ.Micropore development[J].Adsorption Science and Technology,2006,24:55-64. |
| [25] | Vignal V;Morawski A;Konno et al.Quantitative assessment of pores in oxidized carbon spheres using STM[J].Journal of Materials Research,1999,14:1102-1112. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%