Research Of Synthesis And Performance Of Sulfur Corrosion Inhibitor Suitable For Oilfield Produced Water

Taking oleic acid and divinyl three amine as raw material, this research synthesized oleic imidazoline corrosion inhibitor, and carries on the modification, whose product was oleic acid imidazoline quaternary ammonium salt, the imidazoline corrosion inhibitor mixed with different materials to produce five composite corrosion inhibitor. Determined the optimum synthesis conditions by orthogonal test and single factor variable control, so did its optimum reaction conditions of quaternary ammonium. Through electrochemical surface topography and electron microscope scanning test analyze the corrosion inhibitor and mechanism of the synergistic effect of different material.The experimental results show that the optimum synthesis conditions for acid base imidazoline quaternary ammonium salt corrosion inhibitor are as follows time for acylation 3 hours, acylation temperature 160 °C, cyclic time 4 hours, cyclization temperature 220 C ratio of raw materials(i.e., the proportion of oleic acid to divinyl three amine) 1:1.2. Acylation time has the greatest effect in the synthesis process of corrosion inhibitors; the second is the ratio of raw materials, then acylation and cyclization temperature. Imidazoline intermediate and benzyl chloride in the best proportion is 1:1.2,the quaternary ammonium transition temperature 100 C quaternary ammonium 3 hours. Corrosive medium temperature was 55 C p H greater than 5.2,the concentration of corrosion inhibitor added to 80 mg/L. at this point the corrosion inhibition efficiency is the best. The effect of sodium dodecyl sulfate and op- 10 with the imidazoline corrosion inhibitor distribution respectively is not as ideal as corrosion inhibitors mixed with other drugs, but all has same synergistic effect. With thiourea and propiolic alcohol, potassium iodide the distribution effect is better. In addition, thiourea and corrosion inhibitor compound with a ratio of 1:10; Propiolic alcohol and corrosion inhibitor in the best mix proportion is 3:20; The best distribution of potassium iodide and corrosion inhibitors for 3:100;Electrochemical tests show that the electrochemical test results were analyzed, and concluded that the composite corrosion 1,2,3,4 are cathodic control mixed corrosion inhibitor, 5 anode control and composite inhibitor mixed corrosion inhibitor. Make electron microscope scanning test on the composite inhibitor 1 and compound corrosion inhibitor 3. Imidazoline derivatives with corrosive medium in sulfide and Fe form into coordination bond formation, produce a stable adsorption film on metal surface, which has a local corrosion protective effect of H2 S.The inhibitor with propiolic alcohol experienced a condensation reaction in the metal surface, which forms polymer film of imidazoline more compact than the molecules separate form of polymer film, thus reducing the chance a metal surface contact with the corrosive medium. Because of the good effect of anion when mixed with potassium iodide, therefore the research should take the adsorption ability of anion into consideration.