Method for firing porous cristobalite at low temperature by adopting diatomite as raw material

The invention discloses a method for firing porous cristobalite at low temperature by adopting diatomite as a raw material. The method comprises the following steps of: adding diatomite powder into an additive solution, wherein the addition amount of diatomite is 1g/2-5ml according to the ratio of the mass of the diatomite/the volume of the additive solution; fully stirring, and then drying, wherein the additive solution is sodium metasilicate or alkali-metal silicate solution with the mass fraction being 7.20-17.33%; heating the dried solids to 600-800 DEG C, and calcining for 12-24 hours to obtain the porous cristobalite. The method disclosed by the invention has the beneficial effects that since the calcining temperature is low, the cristobalite product retains the morphology of the cristobalite and has abundant pore-channel structures so as to achieve unique and good heat retaining property. The prepared cristobalite has the intrinsic property of other synthesized cristobalites, also retains the morphology of the cristobalite and has abundant pore-channel structures so as to achieve good heat retaining property. The method disclosed by the invention has the advantages of low energy consumption, simple process and low cost and the product has high potential industrial value.