Production of sodium formate

The present invention relates to a method for producing a solid sodium diformate preparation having a formic acid content of at least 35 wt .-%, based on the total weight of sodium diformate preparation, in which at elevated temperature from sodium formate and at least 74 wt .-% formic acid produces an aqueous solution having a molar ratio of HCOOH: 1, bringing the aqueous solution for crystallization and the: HCOONa of greater than 1.5: 1 and a molar ratio of HCOOH: H (I) a subset (A) of the mother liquor used in the preparation of the aqueous solution and (Ii) a subset (B) of the mother liquor treated with a sodium-containing base and the hereby resulting sodium-containing mixture, optionally the same after discharge of a part and optionally of the same after concentration, is also used in the preparation of the aqueous solution; and wherein the subsets (A) and (B) of the mother liquor add up to 100 wt .-%.