Synthesis And Properties Of Quaternary Ammonium Salt Gemini Surfactant Containing Nitrogen Heterocyclic Ring

The demand of energy is increasing with the rapid development of economy.Equipment and pipelines are corroded seriously.And some unnecessary trouble are brought to industrial production.At present,adding some corrosion inhibitors is the most effective way to prevent and administer this kind of corrosion.With its good germicidal efficacy,low toxicity,good water solubility,and extensive biological activities quaternary ammonium salt gradually appeares in people's vision.Nitrogen heterocyclic quaternary ammonium compounds have been widely used in industry.In addition,the degradation of ester compounds as a environmentally friendly material has gradually aroused people's attention.In this paper,hydroxyl imidazoline was first synthesized by the ladder temperature method,using xylene as water carrying agent,oleic acid and N-(2-Hydroxyethyl)ethylenediamine as raw materials.And the effects of temperature,different water carrying agent,water carrying agent content and the ratio of oleic acid and N-(2-Hydroxyethyl)ethylenediamine on imidazoline yield were studied,and the optimum conditions for the synthesis of hydroxy imidazoline were determined.The melting point of the composite was determined and its structure was characterized by IR and 1H NMR.The corresponding ester was generated with homemade imidazoline,adipoyl chloride and metronidazole as raw material,dichloromethane as solvent,three ethylamine as acid binding agent.Gemini quaternary ammonium salt containing nitrogen heterocyclic quaternary ammonium salt was synthesized with chloroacetic acid as quaternary ammonium reagent.The synthesized products were characterized by IR spectra and 1H NMR.Its dispersibility in aqueous solution,the emulsifying ability of benzene in aqueous solution,the foaming ability in water and the stability of foam,and the hydrophilic lipophilic balance(HLB)value were studied,and surface tension and critical micelle concentration of the surfactant were measured by the hanging ring method.The effect of temperature,concentration of the inhibitor and different acid solutions on corrosion inhibition performance for Q235 steel werw studied by weight loss method,polarization curve,electrochemical impedance spectroscopy.And the corrosion inhibition mechanism was briefly discussed.In addition,the corrosion morphology of Q235 steel with and without corrosion inhibitor were observed by SEM.It turned out to be that the optimum conditions for the synthesis of hydroxy imidazoline: mole ratio of oleic acid and N-(2-Hydroxyethyl)ethylenediamine was 1:1.2,20 ml xylene was added into 100 ml three mouth flask,temperature started from 120 ? to 220 ?,elevating 20 ? every two hours.The melting point of the synthesized material was about 83 ?.The substance was proved to be hydroxyl imidazoline by IR and 1HNMR.Quaternary ammonium salt Gemini surfactants containing nitrogen heterocyclic ring was proved to have been synthesized by IR and 1HNMR.The test results showed that the quaternary ammonium salt Gemini surfactant containing nitrogen heterocyclic ring has good dispersion,better emulsifying ability of benzene in water,foaming ability was strong and foam was stable.The surface tension was 33.67 m Nm-1,critical micelle concentration was 1.5×10-3 mol/L.In conclusion,it had good surface activity.In addition,its corrosion inhibition performance was well.The results showed that the corrosion inhibition efficiency could reach 91.12% when the dosage of the surfactant was 90 mg/L in 15% hydrochloric solution at the temperature of 60?,and the corrosion rate decreased while the corrosion inhibition efficiency increased significantly with the increase of the inhibitor concentration.The polarization curves and electrochemical impedance spectroscopy test results showed that the inhibitor was a mixed type inhibitor,and forming protective film on the metal surface through “geometric block effect”.The surface morphology of Q235 steel sheet under scanning electron microscopic observation also proved the quaternary ammonium Gemini surfactant containing ester has good corrosion inhibition performance.