The invention discloses a method for preparing porous
ceramic from
coal gangue. The method is characterized by comprising the following steps of: carrying out acid reaction pretreatment on
coal gangue, carrying out melting pretreatment on the
coal gangue, adding
citric acid and a protective agent, carrying out mixing, stirring until the materials are molten, carrying out mixing,
drying to obtain
coal gangue powder, screening the
coal gangue powder, adding a proper amount of paraffin oil, carrying out aging, carrying out injection molding, carrying out
degreasing, carrying out low-temperature
calcination, and carrying out pressurized high-temperature
calcination to obtain porous
ceramic, wherein the protective agent is
calcium citrate
porous carbon. The method has the beneficial effects that pore forming is completed in a biscuit forming stage by utilizing capillary force formed between
raw material solid particles and two liquid phases; and
alumina of
coal gangue and a
citric acid principle are utilized,
calcium citrate
porous carbon is creatively added, high-pressure
calcination is carried out, generated molten aluminum
chloride is protected, pore forming is completed by utilizingcapillary force formed between
raw material solid particles and two liquid phases,
silicon and aluminum oxides of coal gangue are fully utilized, and the porous
ceramic with catalytic activity is generated by adopting a one-
step method.