Advanced multi-functional asbestos free thermal insulating material and the process for preparation thereof

A process for preparing a multi-functional asbestos free thermal insulating tiles, the process comprising:

• a. dry grinding of 45.45-49.50% of marble waste powder;
• 45.45-49.50% of rice husk and 1 to 9.1% of calcium hexametaphosphate in a ball mill or planetary mill for a period of 8 to 10 hours to obtain a grinded powder;
• b. mixing the grinded powder to an aqueous solution of 50-80% potassium hydroxide to obtain a reaction mixture;
• c. irradiating the reaction mixture obtained in step (b) in a microwave with a power of 200-350 watts for a duration of 10-15 minutes to obtain a precipitate;
• d. filtering the precipitate obtained in step (c) and drying it at 1000 C-1100 C to obtain a solid powder of homogenized nano thermal insulating precursor;
• e. mixing 62.9-76.75% of the homogenized nano thermal insulating precursor with 13.05-18.25% geopolymeric matrix comprising 68.62-68.96% fly ash, 8.82-10.34% potassium hydroxide and 3.45-4.90% potassium silicate and 17.25-17.64% of water to obtain a mixture;
• f. mixing 10.20-18.85% crushed silica fiberglass to the mixture obtained in step (e) to form a material;
• and
• g. compacting the material in the form of tiles of 10 cm×10 cm×8 mm to 10 cm×10 cm×10 mm at a compaction pressure of 100-200 kg/cm2 and heating the tiles in an electric furnace at a temperature range of 1100−1200° C. for a period of 2 to 3 hours.