Design of molecular scale inhibitors for high temperature industrial cooling water systems based on group synergistic effects

In high-temperature industrial circulating cooling water systems, the pursuit of environmentally friendly and efficient scale inhibitors is crucial. This study introduced a novel series of monomers with exceptional scale inhibition properties, designed and optimized using Density Functional Theory (DFT). An in-depth analysis of ρ and ∇2ρ at critical points in the electrostatic potential distribution was conducted through the Atoms in Molecules (AIM) approach. Fukui Function analysis was also employed during the thorough screening of optimal molecular pairs. The result of this study is the development of a new ternary scale inhibitor, MA-IA-VS, which not only demonstrates a strong affinity and high binding energy but also exceptional dispersibility and biodegradability, aligning with the principles of green chemistry. Experimental data indicates that MA-IA-VS effectively inhibits over 99 % of CaCO3 and CaSO4 scales at minimal dosages (30 mg·L-1 and 7 mg·L-1, respectively), yielding substantial environmental and economic benefits. Furthermore, the interaction mechanism between MA-IA-VS and scaling crystals were elucidated through molecular dynamics simulations and mechanistic studies, revealing that MA-IA-VS forms a protective layer on the surface of Fe (110). Additionally, the adsorption of MA-IA-VS prevents calcium scale from adhering to the metal surface and alters its concentration distribution in solution, thus realizing scale inhibition effect. This contributes to a deeper understanding of scale inhibitor mechanisms and establishes a robust theoretical and practical foundation for the design of novel, eco-efficient scale inhibitors.