MANUFACTURE OF NITROGEN OXIDE DECOMPOSING CATALYST

摘要

PURPOSE:To obtain a highly active catalyst by dispersing zeolite in an aqueous copper compound solution and subsequently adding a solution of alkaline earth metal hydroxide thereto to adjust the pH of the resulting dispersion to introduce copper into zeolite within a short time. CONSTITUTION:Y-type or mordenite type zeolite is dispersed in an aqueous solution of a copper compound such as copper sulfate. Next, a solution of alkaline earth metal hydroxide such as magnesium hydroxide or calcium hydroxide is added to the resulting dispersion to adjust the pH of the dispersion to 6.0 or more. Thereafter, zeolite is recovered. By this method, a predetermined amount of a metal can be easily introduced into zeolite within a short time and no ammonia is generated even in pretreatment and nitrogen monoxide is efficiently removed with high activity.