Combined scale inhibition of modified polyepoxysuccinic acid and electrochemical water softening

The combination of scale inhibitor and electrochemical water softening technique is a novel strategy for effective scale inhibition, but selecting the appropriate scale inhibitor remains a challenge. In the work, a novel environmentally friendly scale inhibitor (PL 0.3 ) based on polyepoxysuccinic acid and lysine were synthesized using the dehydration condensation method to complement the electrochemical water softening technique. The compatibility of scale inhibitor and electrochemical water softening (SI/EWS) technique was evaluated by static experiments. The results indicated that SI/EWS can effectively remove scale-forming ions, achieving a precipitation rate of 14.27 g/m²·h at 24 A·m −2 when the PL 0.3 concentration is 6 mg·L −1 . Under these conditions, PL 0.3 remains highly stable in the electrochemical environment, with its scale inhibition performance unaffected the electric field and electrode reactions, achieving an inhibition efficiency exceeding 93 %. The dynamic experiment further demonstrated that SI/EWS technique can effectively inhibit scale. In addition, experiments and molecular dynamics simulations jointly demonstrated that the two unique properties of the weak ability to interfere with crystal nucleation of PL 0.3 around the cathode and its electrostatic repulsion with the cathode are the key factors for the combined scale inhibition of the SI/EWS. This study offers a novel perspective for achieving efficient scale inhibition in circulating cooling water systems.