Preparation And Performance Evaluation Of Mannich Base Acid Corrosion Inhibitor

Three sorts of Mannich base acidification corrosion inhibitors were prepared through Mannich reaction under the condition of acid medium using formaldehyde,homemade aromatic ketone intermediates and organic amines as raw materials.The effects of different reaction temperature,material ratio,reaction time and reaction medium on the corrosion inhibition performance of the prepared inhibitor were investigated based on single factor study.The optimum condition of three sorts of Mannich base acidification corrosion inhibitors were obtained by orthogonal design theory.The corrosion inhibiton performances were evaluated by static weight loss method.The main agent was compounded with BAA,dispersant,unsaturated alcohol A,etc.,and the effect of the addition amount of each substance on the corrosion inhibition performance of the compound inhibitor were explored to obtain a composite inhibitor with synergistic effect.Analysis by electrochemical method found that: MM-1 corrosion inhibitor is a type of inhibitor that inhibits the anode reaction;MM-2 corrosion inhibitor is a mixed type inhibitor that mainly suppresses the anode reaction and supplements the cathode reaction.MM-3 corrosion inhibitor is a type of corrosion inhibitor that inhibits anode reaction.These three inhibitors can form a uniform and stable adsorption film layer on the metal surface without changing the properties of the solution;it is found through adsorption thermodynamics that these three inhibitors form chemical adsorption on the surface of N80 steel sheet and conform to the Langmuir adsorption model;through scanning electron microscopy Electron spectroscopy analysis revealed that the inhibitor molecules can be adsorbed on the surface of the steel sheet to form a complete and dense adsorption film,protecting the metal from corrosion by the medium.The performance indexes of the three types of acidified corrosion inhibitors finally obtained in the experiments can reach SY / T 5405-1996 "Test Methods and Evaluation Indexes for Corrosion Inhibitors for Acidification" in the oil and gas industry.