acetic acid

acetic acid
W. Oelen · CC BY-SA 3.0 · source
Name	Acetic acid
Formula	C2H4O2
Molar mass	60.05 g·mol−1
Density	1.049 g·cm−3 (liquid, 20 °C)
Melting point	16.6 °C
Boiling point	118.1 °C
Appearance	Colorless liquid

acetic acid Acetic acid is a simple carboxylic acid that is a key chemical in industrial chemistry and everyday life. It serves as a building block for the manufacture of polymers, solvents, and food additives and is central to several major chemical industries. Historically significant in industrialization, it remains vital to modern synthesis and materials.

Introduction

Acetic acid is the prototypical carboxylic acid whose structure and reactivity underpin organic synthesis, catalysis, and industrial chemistry. Its prominence has linked it to major industrial firms such as BASF, Dow Chemical Company, ExxonMobil, and DuPont, while academic research groups at institutions like Massachusetts Institute of Technology, University of Cambridge, and ETH Zurich have elucidated its mechanistic behavior. Governments and regulatory bodies including the United States Environmental Protection Agency and the European Chemicals Agency manage its production, transport, and use due to scale and hazard considerations.

Physical and Chemical Properties

As a liquid with a sharp, vinegar-like odor, acetic acid displays hydrogen bonding and association that affect its boiling and melting points; these properties have been characterized in studies at laboratories such as National Institute of Standards and Technology and Max Planck Society institutes. It is miscible with many organic solvents used by firms like Shell plc and Chevron and dissolves in water due to its polar carboxyl group; its acid dissociation constant (pKa) has been accurately measured by researchers at Sorbonne University and California Institute of Technology. The molecule undergoes typical carboxylic acid reactions — esterification, amidation, oxidation, and acid-catalyzed rearrangements — topics explored in textbooks from Wiley and research published through American Chemical Society journals. Phase behavior and vapor pressures have been quantified in international standards bodies, including International Union of Pure and Applied Chemistry guidelines.

Production and Synthesis

Industrial production historically included carbonylation of methanol, a process commercialized by companies like Monsanto and later optimized by BP and Ineos, using catalysts developed in collaboration with universities such as Imperial College London. Alternative routes include acetaldehyde oxidation, historically linked to firms such as Union Carbide, and biological fermentation pathways used by food producers like Heinz and research groups at Wageningen University. Emerging sustainable syntheses apply electrocatalysis and biocatalysis investigated at Lawrence Berkeley National Laboratory and Riken, and processes for recycling and upcycling feedstocks are pursued by startups incubated at Massachusetts Institute of Technology spinout ecosystems. Regulatory frameworks from agencies like Food and Drug Administration influence production for food-grade acetic acid, while international trade of bulk chemical commodities is tracked by organizations such as World Trade Organization.

Applications and Uses

Acetic acid is converted into vinyl acetate monomer, a precursor for polymers produced by companies such as Arkema and Celanese; it is used to make cellulose acetate for film and fiber by manufacturers like Eastman Chemical Company. In the food sector, industrial producers such as Kraft Foods employ acetic acid-derived vinegar for preservation, and breweries and distilleries regulated by agencies like Alcohol and Tobacco Tax and Trade Bureau utilize related fermentation chemistries. In pharmaceuticals, active pharmaceutical ingredient producers working with institutions like Pfizer and Roche use acetic acid in synthesis and purification steps; laboratory suppliers such as Sigma-Aldrich distribute reagent-grade material to academic groups at Harvard University and Stanford University. It also serves as a solvent and reagent in coatings and inks supplied by corporations including PPG Industries and Huntsman Corporation.

Safety and Toxicity

Concentrated acetic acid is corrosive and can cause chemical burns; occupational exposure limits and safety protocols are specified by Occupational Safety and Health Administration and enforced in industrial settings such as refineries operated by TotalEnergies. Toxicological assessments conducted by agencies like World Health Organization and research institutions including National Institutes of Health inform permissible exposure and first-aid measures. Transportation and classification of hazardous materials follow conventions administered by the United Nations Economic Commission for Europe and are implemented by carriers such as Maersk and FedEx for bulk shipments. Material safety data and emergency response planning are resources used by hospitals like Mayo Clinic and industrial hygiene teams at Johns Hopkins Hospital.

Environmental Impact

Large-scale production and release of acetic acid are monitored in environmental programs run by entities such as United Nations Environment Programme and national regulators like Environment Agency (England and Wales) to assess impacts on waterways and ecosystems. Biodegradation is rapid under aerobic conditions, a property utilized in wastewater treatment plants overseen by municipalities including New York City and Tokyo Metropolitan Government, but concentrated spills can cause local pH shifts and harm aquatic species studied by researchers at Scripps Institution of Oceanography. Life-cycle analyses conducted at research centers like Fraunhofer Society and Argonne National Laboratory compare petrochemical and bio-based production pathways for greenhouse gas emissions, informing corporate sustainability programs at companies such as Unilever and Nestlé.

Category:Carboxylic acids