Aerogel preparation method capable of recycling gel solution

The invention discloses an aerogel preparation method capable of recycling a gel solution, which comprises the following steps: step 1) uniformly mixing tetraethoxysilane, absolute ethyl alcohol and deionized water according to a mass ratio of 1:(2-2.5):(0.3-0.35), stirring the mixture for 10-20 minutes at room temperature to obtain a SiO2 gel solution A, and standing for 20 minutes; step 2) preparing a circulating gel solution B, mixing the solution A in the step 1) and the solution B according to a certain proportion, mixing and stirring the mixture for 2-6 minutes, adding a catalyst C01 after the mixing is finished, then stirring for 5-10 minutes, adding a catalyst C02, continuously stirring for 3-10 minutes, and injecting the mixed gel solution into a gel mold filled with fibrofelt forgelling to obtain fibrofelt composite wet gel C; step 3) aging the fibrofelt composite wet gel C obtained in the step 2 for 24 h at room temperature, and after aging is finished, adding a modifier with the mass being 10%-40%