KATADA Naonobu National University Corporation Tottori University, Faculty of engineering, Associate Professor, 工学部, 助教授 (00243379)
NIWA Miki National University Corporation Tottori University, Faculty of engineering, Professor, 工学部, 教授 (10023334)
|Budget Amount *help
¥3,900,000 (Direct Cost: ¥3,900,000)
Fiscal Year 2004: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 2003: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 2002: ¥300,000 (Direct Cost: ¥300,000)
Fiscal Year 2001: ¥2,800,000 (Direct Cost: ¥2,800,000)
Sulfur dioxide formed by the oxidation of sulfur compounds in petroleum or coal burned as fuels cause acid rain. Several methods for the removal of sulfur compounds from the fuels or exhaust gases are utilized. Oxidation and neutralization of sulfur dioxide in the presence of oxygen, water vapor and calcium oxide powder into calcium sulfate (gypsum) has been utilized for a boiler using heavy oil. However, the use of gypsum formed by this process, has been limited in recent years. Therefore, old catalytic reaction, oxidation into sulfuric acid, has again drawn attention.
Oxidation of sulfur dioxide on activated carbon catalysts(AC) were investigated in piston-flow type reactor, at constant temperature. Apparatuses were composed of feed gas systems, reactor, product gas analyzer and exhaust gas treatment systems. 10 kinds of AC, which were prepared from different raw materials and production process, were studied. YS-1 was prepared according to our previous patent, from Japanese cedar, YS
-2 and 3 from waste wood. Other AC were prepared from coconut shell, coal and petroleum pitch.
Comparison of activities was carried out at selected conditions, reaction temperature:45 ℃, total pressure:1 atm, W/F:12.5×10^<-3> g-min/ml. Conversion as catalytic activities showed wide range difference from 32 to 96%. 3 kinds of wooden AC showed particularly high activity.
Physical properties, as characteristics affected on catalyst activities, specific surface area, specific pore volume and image of SEM did not show clear co-relations to activities. Chemical properties, NH_3-TPD,IR,XPS, hydrophobic interactions also studied. As a result, catalysts which have high concentration of oxygen on AC surface and high hydrophobic properties, showed excellent activity. Novel catalyst impregnated PTFE intentionally gave remarkable improvement.
Conceptual design of flue gas desulfurization pointed out the importance of catalyst shape in order to depress pressure drop. After this, honeycomb structure of catalyst shape should play important roles. Less