Abstract: The corrosion of metals in contact with aqueous alkanolamine solution in acid gas removal units is inhibited by adding to the alkanolamine solution a corrosion inhibiting amount of a thiacrown ether compound. The compounds are monomeric or polymeric and have from 4 to about 10 sulfur atoms on each of the crown rings. The polymeric thiacrown ether ring structures are substituted with polymerized ethylenically unsaturated monomers and have from 4 to about 10 sulfur atoms on each of the crown rings. In some embodiments of the invention, a linkage “M” connects the thiacrown ether ring structures and the polymers and M is O; S; COO; C1 to C5 substituted or unsubstituted linear or branched alkylene wherein the substituent is OH, SH, F, Br, Cl, I, COOH, amine, mono- or di- C1 to C5 alkylamino, C1 to C3 lower alkanoylamino or nitro; or M is NR6 where R6 is H or C1 to C5 alkyl.

Abstract: An aqueous stabilized composition for the treatment of surfaces such as metals, particularly aluminum, comprises a tetraalkyl silicate or a monomeric or oligomeric hydrolysis product thereof, an inorganic passenger powder below 100 nanometer diameter such as fumed or colloidal silica and a stabilizer, all dispersed in a fluid aqueous medium. The stabilizer comprises a carboxylic acid polymer, copolymer or salt thereof, preferably an acrylic acid polymer, copolymer or salt thereof, and most preferably a polyacrylic acid.