Synthesis of sodium formate and drilling fluid comprising the same

A system for synthesizing ultra-pure sodium formate, the system comprising:

• a reaction vessel comprising one or more inlets connected to an acetaldehyde feed stream, a formaldehyde feed stream, and a NaOH feed stream, the reaction vessel configured to react acetaldehyde, formaldehyde, and NaOH from the acetaldehyde feed stream, the formaldehyde feed stream, and the NaOH feed stream respectively to form a raw reaction solution comprising pentaerythritol and sodium formate;
• an evaporator downstream of the reaction vessel, the evaporator being configured to reduce the water content of the raw reaction solution and remove unreacted formaldehyde from the raw reaction solution to form a concentrated reaction solution with a formaldehyde concentration less than 0.5% by weight;
• a vacuum crystallizer downstream of the evaporator, the vacuum crystallizer being configured to reduce the temperature of the concentrated reaction solution to form pentaerythritol crystals in suspension while retaining the sodium formate in solution;
• a filtration system downstream of the vacuum crystallizer, the filtration system being configured to remove the pentaerythritol crystals in suspension to create a mother liquor comprising the sodium formate in solution;
• and
• an extraction tower downstream of the filtration system, the extraction tower being configured to separate the sodium formate from the mother liquor by exposing the mother liquor to an extraction solvent selected to absorb the sodium formate.