Light-weight cordierite castable and preparation method thereof

The invention relates to a light-weight cordierite castable and a preparation method thereof. The technical scheme includes that the preparation method includes: using 40-70wt% of porous cordierite ceramic grains, 20-48wt% of cordierite ceramic fine powder, 2-10wt% of calcium aluminate cement, 2-4wt% of talcum fine powder, 2-4wt% of silicon oxide micro powder and 2-4wt% of active alpha alumina micro powder as raw materials, additionally adding water accounting for 8-20wt% of the raw materials and 0.02-1wt% of water reducers, uniformly stirring and molding by casting; and naturally drying molded green bodies for 24 hours and then drying the dried green bodies for 8-48 hours at the temperature of 110 DEG C. The light-weight cordierite castable prepared by the method not only has the advantages of high apparent porosity, small average pore size, high strength, low thermal conductivity, good thermal shock stability and high medium erosion resistance, but also has the advantages of convenience to construct, environmental friendliness, controllability in apparent porosity and pore size and small volume change after firing, and is applicable to backing layers or working layers of high-temperature kilns or containers at the working temperature lower than 1340 DEG C.