CPC B01J 35/57 (2024.01) [B01J 37/0207 (2013.01); B01J 37/0209 (2013.01); B01J 37/08 (2013.01); B01J 2235/10 (2024.01); B01J 2235/15 (2024.01); B01J 2235/30 (2024.01)] | 4 Claims |
1. A method for preparing a honeycomb catalyst, wherein
the honeycomb catalyst is used for catalytic oxidative degradation of Volatile Organic Compounds (VOCs), and
the honeycomb catalyst is prepared by an ultrasonic double-atomization process, comprising
step (1) placing honeycomb in nitric acid solution with mass concentration of 5%-15% for acidification for 6-18 h, cleaning and naturally drying the honeycomb after removal from the nitric acid solution, placing the honeycomb in a hydrothermal reactor, adding alcoholic solution for hydrothermal activation, wherein temperature of the hydrothermal activation is 120-180° C., and time of the hydrothermal activation is 6-18 h, naturally drying the honeycomb after performing the hydrothermal activation and removal from the hydrothermal reactor; wherein the honeycomb is attapulgite honeycomb, cordierite honeycomb, mullite, or silicon carbide honeycomb; wherein the alcoholic solution is ethanol solution with mass concentration of 25%-75%;
step (2) dissolving a soluble transition metal inorganic salt in deionized water and stirring thoroughly to obtain a precursor solution; preparing a precipitant solution; performing ultrasonic atomization of the precursor solution and the precipitant solution in an ultrasonic atomization device into droplets, and placing the honeycomb in a quartz glass reactor, wherein the droplets enter into the quartz glass reactor through a pipeline to come into contact with a surface of a honeycomb hole and rapidly react to generate a hydroxide precursor on the surface of the honeycomb hole; wherein the soluble transition metal inorganic salt is cobalt salt, manganese salt, cerium salt, nickel salt, or zinc salt; and
step (3) drying the honeycomb in a drying box after performing the ultrasonic atomization, and calcining the honeycomb in a muffle furnace to obtain a honeycomb catalyst loaded with the transition metal oxide.
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