Simultaneous production of monophenol chemicals and CO2 adsorbent through salt solution-enhanced pyrolysis of electronic waste plastics

This study presented a novel method for the simultaneous generation of monophenol chemicals and carbon-based CO2 adsorbent from polycarbonate (PC) by using salt solution-enhanced pyrolysis. The regulatory functions of several factors on the production of 4-isopropenylphenol (IPP) and phenol were investigated using a laboratory-scale pyrolysis reactor, including salt solution type (neutral, acidic, and alkaline), solution concentration, and pyrolysis temperature. The results revealed that the Na2CO3 solution exhibited the best ability to enhance the preparation of IPP and phenol. At Na2CO3 concentration of 1 mol/L and pyrolysis temperature of 600 °C, the optimum yields of IPP and phenol reached 28.83 wt% and 33.77 wt%, respectively. The pyrolysis char (PCSC) obtained under this condition exhibited good CO2 adsorption behavior with a maximum adsorption capacity of 1.75 mmol/g at 30 °C because of its well-formed porous structure and copious oxygen-containing functional groups. [Display omitted] •A new strategy for polycarbonate pyrolysis enhanced by salt solution was developed.•The yields of 4-isopropenylphenol and phenol reached 28.83 wt% and 33.77 wt%.•The pyrolysis solid residue had great potential as carbon-based CO2 adsorbent.•The CO2 adsorption capacity of the adsorbent attained 1.75 mmol/g at 30 °C.