| 摘要 |
PURPOSE:To allow NOx in an exhaust gas to be contact-decomposed extremely effectively under conditions in the presence of oxygen by using zeolite containing iron obtained by allowing a specific Y-type zeolite to come in contact with aqueous ferrosalt solution as a catalyst, and also using a hydrocarbon compound as a reducing agent. CONSTITUTION:When NOx is contact-decomposed in the rpesence of oxygen, a catalyst used is zeolite containing iron obtained by allowing Y-type zeolite having a molar ratio of 4.6 or higher of silica for alumina and the content of 2.4wt.% of Na2O to come in contact with an aqueous ferrosalt solution with a pH value of 3 or lower. In addition, a reducing agent used is a hydrocarbon compound. Subsequently, it is possible to decompose NOx efficiently without any adverse effects of sulphur and any significant decrease of catalytic activity. These catalyst and reducing agent are most suitably used for the practical decomposition of NOx in gas exhausted from a combustion furnace or a diesel engine. |
