The Reaserch Of Polyepoxysuccinic Acid (PESA) And Its Combinations On Corrosion Inhibition Properties

Polyepoxysuccinic acid (PESA) is a green water treatment agent without phosphorus or nitrogen and its biology degradability is better. It is has double performance of scale and corrosion inhibition.With maleic anhydride as raw materials, tungstic acid as the catalyst, the hydrogen peroxide as the oxidant, Ca(OH)2 as the. initiator, under certain conditions the target product polyepoxysuccinic acid (PESA) is synthesized, and characterized the molecular structure of PESA with infrared spectrum.By dynamic potential scan polarization curves, the corrosion inhibition of single polyepoxysuccinic acid (PESA) aiming at Q235 carton steel is measured, the research shows that the corrosion rate of PESA increases with the increase of the PESA concentration, but to achieve a better effect, the PESA concentration needed is higher, by single factor experiments and orthogonal tests the composite prescriptions of PESA are developed, in the environmental temperature 30℃, the optimum composite scheme is selected as 50mg/L PESA,6mg/L Zn2+,20mg/L lucose acid sodium,12mg/L BTA, under the above conditions the corrosion rate of Q235 carton steel is 0.04 mm/a, lower than the national standard, and the corrosion rate is 96.3%. Also, the influence of temperature on the prescription is studiedWith the polarization curves and electrochemical impedance spectroscopy (EIS) measured by experiments, the corrosion mechanism of PESA and its composite prescriptions are discussed. The research shows that PESA inhibits the anode process, it is a kind of anode corrosion inhibitor, also be a kind of adsorption membrane corrosion inhibitor. The corrosion mechanism of the composite prescriptions is mainly that the protective films formed on the carbon steel surface by various components overlap, and reduce the area which contacts directly with the corroded environment, thereby reducing the corrosion rate of carbon steel.