Formic acid (HCO2H), also called methanoic acid, is the simplest carboxylic acid. Formic acid was first isolated by the distillation of ant bodies and was named after the Latin formica, meaning “ant.” Its proper IUPAC name is now methanoic acid. Industrially, formic acid is produced by treatment of carbon monoxide with an alcohol such as methanol (methyl alcohol) in the presence of a catalyst.
Formic acid is found both naturally occurring and frequently synthesized in laboratories. It is most naturally found in the stings and bites of many insects, including bees and ants, as a chemical defense mechanism.
Formic acid reacts exothmerically with all bases, both organic (for example, the amines) and inorganic. Reacts with active metals to form gaseous hydrogen and a metal salt. Reacts with cyanide salts to generate gaseous hydrogen cyanide. Reacts with diazo compounds, dithiocarbamates, isocyanates, mercaptans, nitrides, and sulfides to generate flammable or toxic gases. Reacts with sulfites, nitrites, thiosulfates (to give H2S and SO3), dithionites (SO2), to generate flammable and/or toxic gases and heat. Reacts with carbonates and bicarbonates to generate carbon dioxide but still heat. Can be oxidized by strong oxidizing agents and reduced by strong reducing agents. These reactions generate heat. May initiate polymerization reactions or catalyze other chemical reactions. A mixture with furfuryl alcohol exploded [Chem. Eng. News 18:72(1940)].
FORMIC ACID is a colorless liquid with a pungent odor. It is a stable corrosive, combustible, and hygroscopic chemical substance. It is incompatible with H2SO4, strong caustics, furfuryl alcohol, hydrogen peroxide, strong oxidisers, and bases and reacts with strong explosion on contact with oxidising agents.
Due to the −CHO group, Formic acid imparts some of the character of an aldehyde. It can form salt and ester; can react with amine to form amide and to form ester by addition reaction with unsaturated hydrocarbon addition. It can reduce the silver ammonia solution to produce a silver mirror, and make the potassium permanganate solution fade, which can be used for the qualitative identification of formic acid.
As a carboxylic acid, formic acid shares most of the same chemical properties in reacting with alkalis to form water soluble formate. But formic acid is not a typical carboxylic acid as it can react with alkenes to form formate esters.
Air & Water Reactions
Fumes in air. Soluble in water with release of heat.
Formic acid,HCOOH, also known as methanoic acid, is a colorless, pungent, toxic,corrosive liquid that is soluble in water, ether,and alcohol.It is the most highly ionized of the common organic acids and therefore the most corrosive, It reacts readily with many oxidizing and reducing compounds and is somewhat unstable as the concentration approaches 100%, decomposing to carbon monoxide and water.
Formic acid is used as a chemical intermediate and solvent, in dyeing and electroplating processes, and in fumigants. In a reaction with glycerol at 220°C (430 OF), it is a source of allyl alcohol Formic acid has also been employed in brewing(to assist fermentation), as a food preservative, and in the preparation of metallic formates and esters.
Anhydrous formic acid can be obtained by direct fractional distillation under reduced pressure, the receiver being cooled in ice-water. The use of P2O5 or CaCl2 as dehydrating agents is unsatisfactory. Reagent grade 88% formic acid can be satisfactorily dried by refluxing with phthalic anhydride for 6hours and then distilling it. Alternatively, if it is left in contact with freshly prepared anhydrous CuSO4 for several days about one half of the water is removed from 88% formic acid; distillation then removes the remainder. Boric anhydride (prepared by melting boric acid in an oven at a high temperature, cooling in a desiccator, and powdering) is a suitable dehydrating agent for 98% formic acid; after prolonged stirring with the anhydride the formic acid is distilled under vacuum. Formic acid can be further purified by fractional crystallisation using partial freezing. [Beilstein 2 IV 3.]
Special Hazards of Combustion Products: Toxic vapor generated in fires
Liquid causes skin and eye burns. Vapors are irritating and painful to breath. Vapor exposure may cause nausea and vomiting.
ChEBI: The simplest carboxylic acid, containing a single carbon. Occurs naturally in various sources including the venom of bee and ant stings, and is a useful organic synthetic reagent. Principally used as a preservative and antibacterial agent in livestock feed
Induces severe metabolic acidosis and ocular injury in human subjects.
- Since 1896, formic aid is made in European countries by the action of sulfuric acid upon sodium formate, which is produced from carbon monoxide and sodium hydroxide.
- In 1980, the United States Science and Design Corporation developed a carbonylation of methanol to produce formic acid with an annual output of 20,000 tons. The reaction formula is:
- The mixture of liquid ammonia and methanol is used to absorb carbon monoxide at 70 ° C and 32.5 MPa to form formamide, which is then hydrolyzed in an aqueous acid solution.
- Use oxalic acid and glycerol as raw materials being co-heated at 110 ° C to generate oxalic acid monoglyceride. Heat it to decarboxylate and form Monoglycerides formate, then hydrolyze it to obtain formic acid.
- After the formic acid aqueous solution is obtained, a dehydrating agent (for anhydrous magnesium sulfate, anhydrous copper sulfate, etc.), extractive distillation (extracting agent may be trimethylamine, picoline, etc.) may be used for dehydration and purification, and anhydrous formic aic can be obtained.