Corrosion Inhibitors Having Increased Biodegradability and Reduced Toxicity
The invention relates to the use of salts of compounds of the formula (1) and amines of the formula (2) where R 1 is C 1 - to C 30 -alkyl, C 2 - to C 30 -alkenyl, C 6 - to C 30 -aryl or C 7 - to C 30 -alkylaryl, R 2 is C 1 - to C 30 -alkyl, C 2 - to C 30 -alkenyl, C 6 - to C 30 -aryl or C 7 - to C 30 -alkylaryl, or an optionally heteroatom containing organic radical having from 1 to 30 carbon atoms, and R 3 and R 4 are each independently hydrogen, C 1 - to C 30 -alkyl, C 2 - to C 30 -alkenyl, C 6 - to C 30 -aryl or C 7 - to C 30 -alkylaryl, or an optionally heteroatom containing organic radical having from 1 to 30 carbon atoms, where R 3 and R 4 can also form, with the inclusion of the nitrogen atom, a ring having from 5 to 7 ring atoms.
1 . A corrosion inhibitor comprising the salts of compounds of the formula (1)
and amines of the formula (2)
wherein
R 1 is C 1 - to C 30 -alkyl, C 2 - to C 30 -alkenyl, C 6 - to C 30 -aryl or C 7 - to C 30 -alkylaryl,
R 2 is C 1 - to C 30 -alkyl, C 2 - to C 30 -alkenyl, C 6 - to C 30 -aryl or C 7 - to C 30 -alkylaryl, or an organic radical, optionally containing heteroatoms, and has from 1 to 30 carbon atoms, and
R 3 , R 4 are each independently hydrogen, C 1 - to C 30 -alkyl, C 2 - to C 30 -alkenyl, C 6 - to C 30 -aryl or C 7 - to C 30 -alkylaryl, or an organic radical, optionally containing heteroatoms, and has from 1 to 30 carbon atoms, where R 3 and R 4 optionally form a cycle with from 5 to 7 ring atoms including the nitrogen atom.
2 . The corrosion inhibitor as claimed in claim 1 , wherein R 1 is an alkyl or alkenyl group having from 8 to 18 carbon atoms.
3 . The corrosion inhibitor as claimed in claim 1 , wherein one, two or all R 2 , R 3 and R 4 radicals are —CH 2 —CH 2 —OH.
4 . The corrosion inhibitor as claimed in claim 1 , wherein two of the R 2 , R 3 , R 4 radicals are one C 1 - to C 8 -alkyl group and one —(CH 2 CH 2 O) n —H group where n=from 2 to 10.
5 . The corrosion inhibitor as claimed in claim 1 wherein the amine of the formula (2) is a compound of the formula (3)
wherein
R 5 is hydrogen or a C 1-30 alkyl radical optionally containing heteroatoms, and
X is C, O or N.
6 . A device for extraction and transport of hydrocarbons in mineral oil extraction and processing comprising the corrosion inhibitor as claimed in claim 1 .
7 . A metal processing assistant comprising the corrosion inhibitor as claimed in claim 1 .
8 . A process for making a salt comprising the step of reacting compounds of the formula (1)
with amines of the formula (2)
wherein
R 1 is C 2 - to C 30 -alkyl, C 2 - to C 30 -alkenyl, C 6 - to C 30 -aryl or C 7 - to C 30 -alkylaryl,
R 2 is C 1 - to C 30 -alkyl, C 2 - to C 30 -alkenyl, C 6 - to C 30 -aryl or C 7 - to C 30 -alkylaryl, or an organic radical, optionally containing nitrogen atoms, and has from 1 to 30 carbon atoms, and
R 3 , R 4 are each independently hydrogen, C 1 - to C 30 -alkyl, C 2 - to C 30 -alkenyl, C 6 - to C 30 -aryl or C 7 - to C 30 -alkylaryl, or an organic radical, optionally containing heteroatoms, and has from 1 to 30 carbon atoms, wherein R 3 and R 4 optionally form a cycle with from 5 to 7 ring atoms including the nitrogen atom.