Plastic Waste Management: Polymer Kinetics, Mechanical & Chemical Recycling, and Microplastic Mitigation
Plastic waste management addresses the rapid accumulation of non-biodegradable synthetic polymers (such as Polyethylene Terephthalate [PET], High-Density Polyethylene [HDPE], Polyvinyl Chloride [PVC], and Polypropylene [PP]) in municipal solid waste streams. Characterized by high chemical stability and resistance to natural weathering, plastic waste requires specialized material recovery, mechanical reprocessing, and advanced chemical recycling kinetics to prevent long-term environmental accumulation. The thermal degradation of polymers during thermochemical recycling (such as pyrolysis and gasification) follows non-isothermal reaction kinetics evaluated using the Arrhenius Kinetic Equation : $$\frac{d\alpha}{dt} = k(T) \cdot f(\alpha) = A \cdot \exp\left(-\frac{E_a}{R \cdot T}\right) \cdot (1 - \alpha)^n$$ Where $\alpha$ is the degree of thermal conversion ($\frac{m_0 - m_t}{m_0 - m_\infty}$), $m_0$ is initial mass, $m_t$ is mass at time $t$, $m_\infty$ is final residual mass, ...