A sustainable and recycle strategy of rigid polyurethane from waste refrigerator to high-valued supercapacitor
摘要
The sustainable disposal of waste polyurethane (WPU) from refrigerators has garnered increasing attention. Based on the principles of waste utilization, we proposed a sustainable and up-recycle strategy to use WPU to construct high-valued supercapacitors through pyrolysis, activation and synthesis. The average activation energy (Ea) for WPU pyrolysis was about 143 kJ mol− 1; about 80% volatile content was removed after pyrolysis at 600 °C. The activation played a key role in constructing a porous structure via etching and templating effects. The results showed that the optimum parameters for activation process were the mass ratio of pyrolysis residue (PR), KOH and KCl of 1:3:1, the activation temperature of 800 °C, and the retention time of 60 min. The obtained supercapacitors based on WPU exhibited high specific capacitance, remarkable cycling stability and electrochemical reversibility at three- and two-electrode tests. Based on the above analysis, the up-cycle method of WPU was established. Moreover, the results of economic evaluation showed that this up-cycle of WPU generates a profit of $2445.15 every day. This study may contribute to new insights into the disposal of WPU and aims to realize the sustainable recycling of waste.