Optimizing the Recycling Process of PP Plastics from Waste Washing Machines: Sustainable Strategy for Environmentally Friendly Reutilization

The resource utilization of waste plastics is an inevitable trend toward achieving sustainable social development. The plastic in waste washing machines is a highly potential source of recycling. This study developed a strategy for effectively regenerating PP plastics from waste washing machines. The optimal process parameters of friction alkali washing were determined through response surface curve analysis. Under the conditions of 280 rpm, 10 min, and pH = 12, the proportion of black spots and impurities decreased to the lowest amount of 11.69 × 10–3 wt %. Additionally, a physical sorting, granulation, and regeneration process was constructed. Large-scale data statistical analysis indicated that recycled PP plastics exhibited excellent stability of physical performance and impurity content. Meanwhile, different formulations were designed to modify and improve the physical properties of the recycled PP. This study achieved the regeneration of PP plastics from waste washing machines and provides theoretical and practical guidance for the environmentally friendly reutilization of waste plastics.