Effects of g-C3N4/MMT Composite on High Rheological Behaviors and Catalytic Properties of Asphalt

Abstract

The adverse impact of vehicle emissions on the roadside environment is becoming increasingly serious. Traditional catalytic materials exhibit a singular practical effect and are prone to aggregation within asphalt systems. This study employed organic montmorillonite (MMT) as a two-dimensional nanomaterial load-bearing phase for graphitic carbon nitride (g-C3N4) based on the structural features of available materials and the concept of composite material construction, resulting in the synthesis of a g-C3N4/MMT composite material (CN-M). The phase composition, binding behavior, thermal stability, physical adsorption capacity, and morphology of CN-M were studied systematically. The results demonstrate that CN-M possesses stable properties and structural morphology. The specific surface area of CN-M is 3.38 times that of g-C3N4, indicating superior spatial confinement capabilities. A comprehensive analysis was conducted from both macroscopic and microscopic perspectives on the modification mechanism, rheological characteristics, aging behavior, and catalytic performance of the modified asphalt. It is speculated that CN-M disperses in a layered state within the asphalt binder, effectively restricting the movement of asphalt macromolecular chains. When the CN-M content reached 5%, the modified asphalt exhibited a high-temperature critical temperature of 71.6°C, showcasing optimal high-temperature rheological performance and aging resistance. The prepared modified asphalt mixture demonstrated the ability for waste degradation, achieving a degradation rate of 21.66% for nitric oxide (NO). The research results provide technical support for the development and application of catalytic asphalt materials.