Method for producing sodium formate

Abstract

The invention relates to a method for producing sodium formate, and comprises the following technique processes: 1. taking n-butanal, formaldehyde solution and caustic soda liquid as raw materials, carrying out low temperature condensation to obtain a condensation solution, and acidating with formic acid followed by pre-treatment; 2. concentrating the condensation solution; 3. extracting the condensation solution in an extracting tower with an alcohol organic solvent containing 5-9 carbon atoms, leading the organic phase after extracting into the bottom part of a bath tower, amplifying the inner diameter dimension of the top part of the bath tower accounting for 5-30% of the height range of the bath tower by 10-50%, carrying out countercurrent washing on the organic phase by using de-ionized water or aqueous solution saturated by trimethylolpropane, the aqueous phase after washing into the upper part of the extracting tower to countercurrent contact with an extract and an oil phase entering afterwards; 5. transferring the extracted aqueous phase into an evaporating kettle to concentrate the sodium formate solution; 5. after relieving vacuum, transferring the concentrated sodium formate solution into a crystallizing kettle, and cooling to below 37 DEG C; 6. centrifuging; and 7. drying. The method of the invention can guarantee the quality of the main product trimethylolpropane and enhance the yield and quality of sodium formate.

Description

(1) Technical field [0001] The present invention relates to a kind of method of producing sodium formate, especially the method for by-product sodium formate when producing polyol. It belongs to the technical field of organic chemical products. (2) Background technology [0002] Sodium formate is one of the main raw materials for the production of formic acid and oxalic acid, and is also a raw material for the production of hydrosulfite. In leather processing, textile dyeing and electroplating industries, it is used as raw hide treatment agent, leveling agent and accelerator respectively. It can also be used for the matting of rayon. Since it decomposes into hydrogen and sodium bicarbonate at low temperatures, it is also a hydrogen storage substance. [0003] Sodium formate can be produced industrially by using liquid caustic soda and coke as raw materials, and producing sodium formate through processes such as gas generation, dust removal, causticization, alkali blending...

AI Technical Summary

Problems solved by technology

However, one of the biggest problems of this method is that since the extracted organic phase is not washed with water, not only will some sodium formate still be mixed in the organic phase, but also the sodium formate in the aqueous phase will be lost, and the yield of sodium formate will decrease.

The facts of the polyol production industry have proved that even if the organic phase contains only a small amount of sodium formate, it will promote the decomposition of polyols when heated in the subsequent separation process of polyols, affecting the product quality of polyols.