Halogenated compounds

Buyers use these chemicals as solvents for degreasing and extraction, as intermediates for plastics, pharmaceuticals and agrochemicals, as refrigerants and blowing agents, and as flame retardants. Typical specifications include assay by GC, water, acidity as HCl, non-volatile residue, stabiliser system and colour. For building blocks, ask for the isomeric purity because positional isomers are common impurities.

Regulation is heavy. Ozone depleting substances are controlled under the Montreal Protocol, many fluorinated gases are being phased down, several chlorinated solvents face use restrictions, and persistent compounds such as PFAS and some brominated flame retardants are restricted or banned. Halogenated hydrocarbons fall under HS heading 2903, while halogenated phenols, acids and amines follow the heading of their main function.