Preparation, application, and anti-icing performance of a composite oil film-encapsulated anti-icing agent

In the subtropical winter monsoon mountain regions of southeastern China with a one-month freezing period, the anti-icing fog seal course material is highly applicable to pavement deicing, while its effectiveness is impeded by premature demulsification caused by low-freezing-point filler. A composite oil film-encapsulated anti-icing agent was prepared using sodium chloride as the core material and waste engine oil/kerosene-diluted asphalt as the encapsulation material, and its preparation process was optimized through response surface methodology. The anti-icing agent content and optimal spraying rate of the fog seal course material were determined while verifying its pavement performance indicators against the standard. The scanning electron microscopy test, immersion test, freeze-thaw cycle test, wet wheel abrasion test, and field verification were employed to evaluate the long-term anti-icing performance and durability of the materials. The results indicate that the optimal mass ratio of waste engine oil, kerosene and base asphalt in the encapsulation liquid is 3.1 %, 4.6 % and 92.3 % respectively, with an encapsulation liquid temperature of 62.7 ℃. When the anti-icing agent content is 20 % and the recommended spraying rate is 0.6–0.9 kg/m 2 , the fog seal course material exhibited excellent pavement performance. Before the deicing salt leached through surface micro-cracks, the encapsulation material provided a short-term water-resistant effect lasting up to 2 h, therefore avoiding premature demulsification. The anti-icing agent achieved an effective salt release amount of 90.6 %. The anti-icing fog seal course material demonstrated required durability and long-term anti-icing performance. • Waste engine oil was minimally reutilized as a diluent in composite oil film encapsulation liquid. • The preparation process of the composite oil film encapsulation liquid was optimized using response surface methodology. • A composite oil film-encapsulated anti-icing agent effectively prevents premature demulsification of emulsified asphalt.