Upgrading of low-grade metallurgical coke by CH_4 cracking
Grant-in-Aid for international Scientific Research
|Allocation Type||Single-year Grants|
|Research Institution||Graduate School of International Cultural Studies, Tohoku University|
SHIGENO Yoshihito Tohoku University, Associate Professor, 大学院・国際文化研究科, 助教授 (70108570)
EVANS J.W University of California, Professor, 資源材料工学科, 教授
|Project Period (FY)
1994 – 1996
Completed(Fiscal Year 1996)
|Budget Amount *help
¥6,800,000 (Direct Cost : ¥6,800,000)
Fiscal Year 1996 : ¥2,400,000 (Direct Cost : ¥2,400,000)
Fiscal Year 1995 : ¥1,900,000 (Direct Cost : ¥1,900,000)
Fiscal Year 1994 : ¥2,500,000 (Direct Cost : ¥2,500,000)
|Keywords||methane / pyrolysis / coke / CVI / activated charcoal / pore / micropore / mesopore / Chemical Vapor Infiltration / マイクロポア- / サブマイクロポア- / 微細気孔 / 炭化水素熱分解 / C充填 / BJH法 / Tプロット / 黒鉛 / 移動層|
1. In order to modify the coke so as to increase the oxidation resistance, coke was infiltration by methane cracking. The pore structure change of metallurgical coke accompanying infiltration and oxidation was observed. It was proved experimentally that the mechanical strength after oxidation for the infiltrated coke was higher than for untreated coke. The result is summarized as follows :
1) Coke reactvity index (CRI) decreased from about 32 to 18 by infiltration.
2) The mechanical strength of coke after reaction (CSR) was measured for the infiltrated coke. The index of CSR increased from about 56 to 77 which corresponds to the value of the extremely high grade coke.
3) The enhancement of CSR is caused by the deposited carbon in meso-pores, preventing from increase in the area of micropores during oxidation.
2. To ellucidate the mechanism of infiltration of micropores, an activated charcoa was used as a sample. The meso-and the micropores including submicropores were characterized by use of N2 adsorption-desorption method. The meso-and macropores were also characterized by mercury porosimety. The conclusions are summarized as follows.
1) The volume and the surface area of micropores of the infiltrated activated charcoal are reduced to about 0.1 and 0.2% of those of the original sample, respectively. Among the micropores, the submicropore is filled completely. Concerning the mesopore and the macropore, the decrease ratio is about 3% and 32% for volume and surface area, respectively.
2) When oxidized, the carbon which deposited in macropores is almost burned but that in meso-and micropores is only partly burned ; The ratio of increase in surface area of the infiltrated sample is smallest for the micropores. From these experimental results, it is deducible that the deposited carbon in micropores plays the major role for blocking CO2 intruding, thereby the resistance against oxidation is enhanced.
Research Output (11results)