Method for preparing aerogel

A method of preparing an aerogel, comprising:

• reacting water glass with a first material in a reaction tank to obtain a hydrogel;
• transferring the hydrogel to a solvent substitution tank and then reacting the hydrogel with a second material in the solvent substitution tank to obtain an organogel;
• and
• transferring the organogel to a dryer and then drying the organogel in the dryer to obtain aerogel powder,
• wherein the first material includes pure water, nitric acid, and hexamethyldisilazane (HMDS),
• the second material is not input into the reaction tank, and
• the second material includes n-hexane.