Surfactant Properties of Alkylbenzyldimethylammonium Chloride Oilfield Corrosion Inhibitors

摘要

We have investigated the surfactant properties, including aggregation, partitioning between oil and aqueous phases and adsorption to different surfaces of a homologous series of alkylbenzyldimethylammonium chloride (CnBDMAC) corrosion inhibitors with alkyl chain lengths from 10 to 16 carbons for different concentrations of brine and temperatures. Air-water surface tension measurements have been used to determine the critical micelle concentrations (CMC) and the isotherms for adsorption at the air-water surface. The phase behavior in mixtures with different oils and the surfactant distribution to oil together with measurements of how oil affects the corrosion rate inhibition are discussed. The effects of surfactant chain length, brine concentration and temperature on the equilibrium adsorption isotherms measured for CnBDMAC adsorbing from aqueous solution to different solids, including mild steel, iron carbonate and sand, are described. Results showing how corrosion rate inhibition is related to the extent of adsorption are discussed.