Method for producing hydrophobic silica aerogel blanket, and silica aerogel blanket

A method for producing a silica aerogel blanket, the method comprising:

• preparing a silica sol containing a water glass solution;
• impregnating the silica sol into a substrate for a blanket;
• preparing a wet gel by gelling the silica sol while the silica sol is impregnated into the substrate for a blanket;
• surface-modifying the wet gel with an alkyldisiloxane-based compound while immersing the wet gel in an acid mixture aqueous solution containing acetic acid and an acid catalyst;
• and
• drying the surface-modified wet gel,
• wherein the acetic acid is used in an amount of 0.5 L to 10 L per 1 L of the wet gel, and the acetic acid concentration (w/w %) after the immersing the wet gel is 30% to 90%.