Synthesis And Application Of Aqueous Corrosion Inhibitors

Corrosion is prevalent occurring,owing to natural conditions(like wet air,acid rain),acid pickling,oil field acidizing,and using inhibitors is one of the most efficient methods to prevent corrosion.Imidazoline derivative as a low toxic,efficient and high temperature resistance inhibitor,is a research hot spot at present.In this article a seris of imidazoline is synthesized with different fatty acid,then modified by quaternary ammoniation,and the products are characterized by IR and UV.The influencing factors are studied in corrosion inhibition,such as hydrophobic group,unsaturated bond,quaternary ammoniation.The corrosion conditions are also studied,such as concentration,temperature,acidity,corrosion time,which have an important effect on corrosion inhibition.The results show,linolenic acid imidazoline quaternary ammonium can greatly inhibit corrosion on metal surface and have a effective high temperature resistance. According to Langmuir adsorption isotherm,negative value is calculated for the energy of adsorption indicating the spontaneity of the sdsorption process.The corrosion mechanism is discussed.A series of 1,2-ethane bis(dimethyl alkyl(C_nH_2n+1)ammonium bromide) is synthesized, namely n-2-n·2Br,and characterized by MS and IR.The factors which influence reaction are carried on the discussion.The surface tension of the Gemini surfactantγ_cmc,critical micelle concentration cmc value and inhibiton effect are determined.The result shows good inhibition effect by fitting the experimental data with Langmuir adsorption isotherm,and the inhibition effect reaches maximum at an optimal concentration near CMC(critical micelle concentration). The corrosion mechanism is also discussed.The synergistic inhibition effect for the two types of compounds synthesized with organic and inorganic inhibitors is investigated.It shows obvious synergistic effect,and the inhibition effect is better than industrial inhibitor CT1-3B.The weight loss measurement,scanning electron microscope and laser scanning microscope are applied to corrosion inhibition evaluation,it is found that the inhibitors have a excellent inhibition performance on metal.