METHOD OF PROCESSING A HOT TECHNICAL PENTAERYTHRITE-FORMIATE MOTHER LIQUOR Russian patent published in 2020 - IPC C07C27/26 C07C29/78 C07C51/43 C07C31/24 C07C53/06 

FIELD: technological processes.

SUBSTANCE: present invention relates to a method of processing a hot technical pentaerythrite-formiate mother liquor, comprising introducing into the mother liquor reagents, cooling a mixture of the mother liquor and the reagent while stirring, holding the suspension at a certain temperature, separating the residue from the mother liquor, recycling the formed precipitate and the liquid phase. Reagents used are part of the precipitate of pentaerythrite and water, wherein at first a precipitate of pentaerythrite is formed in an amount of not less than 5 % by cooling the hot mother liquor to 95 °C, then water is added to initial hot mother liquor in amount of 25–40 % to weight of initial mother liquor, then mother liquor is cooled to temperatures of 50–30 °C at rate of 0.3–1.0 deg/min, holding suspension at final crystallisation temperature is carried out while stirring for at least 60 minutes, precipitating precipitate of pentaerythrite while cooling mother liquor to 50–30 °C is separated from solution by centrifugation or filtration with precipitation washing with water, precipitate of pentaerythrite is washed with water with temperature of not more than 20 °C in amount of 10–20 % of the weight of the precipitate and is fed into the pentaerythrite production cycle, and the liquid phase is fed for evaporation to obtain sodium formate, the washing solution formed after washing the precipitate is sent to dilute the initial mother liquor.

EFFECT: disclosed method enables to eliminate contamination of pentaerythrite and sodium formate with salts of sodium chloride or nitrate to obtain acceptable yield and purity of semi-products, which enables to use them in production of sodium formate and pentaerythrite.

1 cl, 1 tbl, 9 ex