Preparation and Application of Double-Hydrophilic Copolymer as Scale and Corrosion Inhibitor for Industrial Water Recycling

Abstract A novel double-hydrophilic copolymer (acrylic acid-isoprenyl polyethoxy carboxylate, AA-TPEL) is synthesized and the structural properties are identified by FT-IR, 1 HNMR and GPC analyses. The inhibitory behavior of the copolymer is determined by using a static scale inhibition method. It is shown that AA-TPEL exhibits an excellent ability to control the formation of CaCO 3 scale with an inhibition efficiency of 88.67 % at the 8 mg L –1 , and it still maintains a superior efficiency even at increasing solution temperature, pH, and Ca 2+ concentration. Weight loss test, potentiodynamic polarization and electrochemical impedance spectroscopy are applied to investigate the inhibition efficiency on mild steel corrosion. All measurements show that, AA-TPEL acts as an efficient corrosion inhibitor and also displays a superior ability to prevent the corrosion of mild steel with approximately 83.21 % inhibition efficiency at the low level of 10 mg L –1 . Scanning electron microscopy (SEM) and X-ray powder diffraction (XRD) are used to characterize the surface morphology of CaCO 3 and steel.