by Monochloroacetic acid, also known as chloroacetic acid or MCAA, is an organic compound with the chemical formula ClCH2COOH. It is a colorless crystalline solid that is highly soluble in water and many organic solvents. MCAA was first prepared in 1859 by the German chemist Hermann Kolbe through the reaction of chloroacetyl chloride with water. Commercially, it is produced by treating chloroacetic anhydride with water.
Uses and Applications of MCAA
MCAA finds a variety of industrial applications due to its reactivity and functional group substitutions. Some of its major uses are:
Herbicide Production
– Monochloroacetic Acid serves as an important starting material in the production of several pre-emergent and post-emergent herbicides. Herbicides containing MCAA include 2,4-D, MCPA, mecoprop and dichlorprop. They act by inhibiting plant cell growth and are widely used globally.
Production of Carboxymethyl Cellulose
– When treated with alkali, cellulose reacts with MCAA to form carboxymethyl cellulose (CMC). CMC finds applications as a thickener, emulsifier and stabilizer in foods, cosmetics, pharmaceuticals and other industries. It is valued for its water solubility and viscosity-enhancing properties.
Glycine Production
– MCAA is reacted with ammonia gas to produce glycine in the Lonza ammonolysis process. Glycine is an important amino acid with applications as a food additive, pharmaceutical excipient and solvent.
otras – Other uses of MCAA include production of drugs like phenylbutazone, detergent builders, dyestuffs, resins and personal care products. Due to its reactivity, it also acts as an important C1 building block in organic synthesis.
Health and Environmental Hazards
While versatile, Monochloroacetic Acid poses significant threats to human and environmental health due to its high toxicity. Some of the major hazards are:
– Corrosiveness – MCAA is a strong acid that can cause severe burns upon contact with skin, eyes and respiratory tract on inhalation of mists or vapors. Prolonged exposure can lead to blindness or even death.
– Carcinogenicity – The International Agency for Research on Cancer has classified MCAA as a possible human carcinogen based on animal studies. Chronic occupational exposure increases cancer risks.
– Aquatic Toxicity – MCAA is toxic to aquatic organisms like fish and daphnia at low concentrations. It can cause long term adverse effects in the aquatic environment due to persistence.
– Soil Contamination – Spillages of MCAA containing wastes can contaminate soils and inhibit plant growth due to phytotoxicity. This affects ecological balance.
– Methemoglobinemia – Ingestion of MCAA may lead to methemoglobinemia, a condition where abnormal levels of methemoglobin are produced interfering with oxygen delivery.
Regulations and Safe Handling
In view of the health hazards, many countries and organizations have strict regulations governing the production, transportation, storage and disposal of MCAA. Some of the key compliance guidelines are:
– Workplace Exposure Limits – OSHA in the USA and ACGIH have fixed an 8-hour time weighted average permissible exposure limit of 0.5 ppm for MCAA.
– Packaging and Transportation – MCAA must be packaged in UN certified strong acid resistant packaging and transported as hazardous chemical under proper labeling as per IMDG code.
– Spill Response – Facilities must have emergency response and spill cleanup plans in place. Spills should be contained using absorbents and neutralized before disposal.
– Waste Disposal – Waste streams containing MCAA require alkaline neutralization to a non-hazardous pH before disposal as chemical waste as per local environmental regulations.
– PPE – Appropriate PPE like head-to-toe acid resistant suit, gloves, goggles and gas mask should be worn during any handling operations.
With adequate safety precautions and regulatory conformance, MCAA can be safely utilized in manufacturing processes harnessing its reactivity. But due its toxicity profile, alternatives are desirable wherever possible. Continuous research strives to develop replacement green chemicals.
*Note:
1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it
