Res. Chem. Intermed.
, Vol. 28, No. 5, pp. 451–459 (2002)
Also available online - www.vsppub.com
Effect of ultra- ne gold particle addition to metal oxides
in ethylene oxidation
and DO-JIN LEE
Department of Chemical Engineering and Nanotechnology Center, Sunchon National University,
315 Maegok-dong, Sunchon, Chonnam 540-742, Republic of Korea
Department of Agricultural Education, Sunchon National University, 315 Maegok-dong, Sunchon,
Chonnam 540-742, Republic of Korea
Received 20 September 2001; accepted 30 November 2001
Abstract—Oxidation of ethylene was carried out over alumina-supported metal oxide catalysts
and highly dispersed gold catalysts, respectively, under atmospheric pressure. The ethylene was
completely oxidized to produce carbon dioxide and water with both metal oxide and gold catalysts.
The activity of gold catalyst prepared by deposition method was much higher than that of supported
metal oxide catalysts. Ultra- ne gold particles on Co
were more active than on Al
catalysts were more active than MoO
catalyst. The activity
of the supported metal oxide catalysts was greatly enhanced by addition of gold particles. It was
therefore considered that gold particles promote dissociative adsorption of oxygen and the adsorbed
oxygen reacts with adsorbed ethylene on support adjacent to the active site.
Most fruits produce large amounts of ethylene hormone during storage [1, 2]. For
example, mature-green tomatoes at harvest evolve ethylene at a rate of
when they are stored at 20
C. The evolved ethylene enhances the
softening of the fruits, so it must be removed in order to extend ripening periods .
Since concentration of the evolved ethylene during fruit storage is extremely low,
up to date, it is known that the ethylene gas can be removed by means of adsorption,
absorption, and catalytic oxidation, etc. Among the methods, we paid attention to
the catalytic oxidation because fruits should be stored at optimum temperature. Be-
cause the commercial catalyst system is expensive, a cheap and effective catalyst
system needs to be developed.
To whom correspondence should be addressed.