Reactive yellow DF-3KS synthesis method

The invention relates to a reactive yellow DF-3KS synthesis method, which comprises: beating 2-naphthylamine-3,6,8-trisulfonic acid, adding hydrochloric acid and NaNO2, and carrying out a reaction to obtain a diazonium salt; beating 3-aminophenylurea, adding sodium hydrogen carbonate and the obtained diazonium salt, and carrying out a reaction to obtain a conjugate; adding the obtained conjugate to a beaten cyanuric chloride suspension, and carrying out a reaction to obtain a first condensate; adding beta-sulfate ethyl sulfone aniline to the obtained first condensate, and carrying out a reaction; and removing inorganic salts from the obtained solution through an ion membrane, and carrying out spray drying. With the method of the present invention, the ecological environment deterioration can be reduced, the raw material cost can be reduced, and the product yield can be improved.