| Summary: | 碩士 === 中原大學 === 化學工程研究所 === 84 === The heterogeneous reduction of N2O by carbon was studied in a
thermogravimetric analysis system, employing pseudosteady
reaction method. The reactions were carried out at temperatures
from 673 to 923 K, and at N2O partial pressures in the range of
10.1-101kPa.A relatively pure carbon derived from phenolic res-
in was used, and the heat treatment temperatures are 1223 and
1323K.The N2O-carbon reaction can be divided into two temperat-
ure regimes.The change of reaction activation energy implies
the reaction is controlled by different mechanisms in different
temperature regimes.The reaction order with respect to N2O pre-
ssure is not constant. It was found that the reaction order be-
come negative when the N2O pressure is higher . The results su-
ggest the increased formation of C(N2O)m complexes at higher N2
O pressures to hinder the reaction . As a comparison,the carbon
was gasifide in O2 at temperature between 573 and 673K and O2
pressures in the reange of 10.1-101 KPa.The activation energy
and reaction order with respect to O2 pressures are 130 KJ/mole
and 0.64, respecivly . Surface structrues of the carbons
gasified in N2O and O2 are different . Higher surface area is
developed for carbon gasifi ed in O2 than in N2O.The carbon
reactivity, based on perunit su rface area of the carbon , in
O2 remains relativly constant at various extents of burn-off
.Howeraver, the reactivity in N2O decraeases with the increase
of the burn-off level.
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