| 摘要 |
PROBLEM TO BE SOLVED: To deodorize a combustion gas containing a slight amount of aldehydes even in a low temperature range by oxidizing the aldehydes in the combustion gas by passing the combustion gas through an oxidation catalyst, which is produced by depositing platinum on a zeolite. SOLUTION: This oxidation catalyst is produced by depositing platinum on a zeolite. The deposition amount of platinum to the weight of the zeolite is controlled to be preferably within a range from 0.1 to 2 wt.% to the weight of the zeolite. The oxidation catalyst is efficient at about 110 deg.C or higher combustion gas temperature and, for example, aldehydes as low as 10 ppm in a combustion gas at about 200 deg.C can be oxidized to 3-4 ppm or lower. A catalyst layer formed by using such a catalyst may be installed at any position shown as a letter A or B in a gas discharging pipe 17. From that point, since the catalyst is efficient at about 110 deg.C or higher, it is sufficient to install the catalyst in a middle or in the outlet of the gas discharging pipe 17 not in a leading pipe 2 before a heat exchanger 3 or a high temperature part of immediate after the heat exchanger 3. |
