To obtain a catalyst capable of reducing and removing NOx from waste gas after dusulfurization of stack gas at a stable rate of denitration over a long time in the presence of ammonia by carrying a vanadium compd., a bromine compd., a copper compd., a compd. of lanthanum, etc., and a compd. of molybdenum, etc., on a carbonaceous material.
A vanadium compd., a bromine compd., a copper compd., a molybdenum or tungsten compd. and a lanthanum or cerium compd. are carried on a carbonaceus material to obtain the objective catalyst having high catalyst activity of densitration at a low temp. of about 100°C, producing little nitrous oxide as a by-product and capable of stably maintaining reduction denitrating performance over a long time even at a high space velocity. When this catalyst is used for treating waste combustion gas at a low temp. freed of SOx from an apparatus for wet-desulfurizing stack gas, residual NOx can be continuously removed with a compact apparatus in an easy and smooth manner.
UMEHARA YOICHI
SONEHARA HISANORI
KANAI RYUICHI
TOKARI OSAMU
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