The invention belongs to the technical field of
silicon dioxide preparation, and provides
silicon dioxide wet gel with narrow
particle size distribution and a preparation method and application thereof, and the preparation method comprises the following steps: S1, preparing a
sodium silicate solution and a
sulfuric acid solution; s2, adding a
sodium sulfate solution, heating, dropwise adding a
sulfuric acid solution until the pH value is 1.2-2.6, dropwise adding acid and alkali at the same time, and keeping the reaction pH value to be 1.2-2.6; s3, adding
sodium dodecyl
benzene sulfonate when the
sodium silicate solution is added to 6m < 3 >; s4, adding
polyethylene glycol when the
sodium silicate solution is added to 12 m < 3 >; s5, when the
sodium silicate solution is added to 27m < 3 >, stopping dropwise adding the sodium
silicate solution and the
sulfuric acid solution; and S6, carrying out
wet grinding, washing and packaging treatment to obtain the
silicon dioxide wet gel. The prepared
silicon dioxide wet gel particles are uniform in
particle size distribution and small in particle size, the
toothpaste prepared from the
silicon dioxide wet gel particles is moderate in gravel feeling, appropriate in consistency, fine and smooth in
toothpaste body and smooth in taste, and the
performance quality of
toothpaste products is improved.