Fixed-bed CO2 adsorption onto activated char from the pyrolysis of a non-recyclable plastic mixture from real urban residues

The potential use of activated char obtained from the pyrolysis of a mixture of non-recyclable plastics for the adsorption of CO2 in fixed-bed columns has been explored. The rejected fraction of plastics collected in a municipal solid treatment plant was pyrolyzed and the resulting char residue was activated to develop a porous carbonaceous material. The dynamic behavior of CO2 adsorption was assessed by the breakthrough curves ob-tained in continuous column tests. Among all the available models, the curves were successfully fitted to the dose-response model. The effect of adsorption temperature (15-45 oC), the inlet CO2 concentration (10-40 %, vol.), and the adsorbent length of the bed (loadings, 1-2 g) on the efficiency of the process was evaluated by the surface response methodology applying an adaptative neural fuzzy inference system (ANFIS). A temperature rise exerted a negative effect on the adsorption capacity due to the physisorption properties of the process, the fed CO2 concentration displayed a positive effect and the fixed-bed length did not play a remarkable influence.

Automated summary

The potential use of activated char obtained from the pyrolysis of non-recyclable plastics for CO2 adsorption in fixed-bed columns was investigated. The plastic waste collected from a municipal solid treatment plant was pyrolyzed to produce char residue, which was then activated to create a porous carbonaceous material. Continuous column tests demonstrated successful fitting of breakthrough curves to the dose-response model. The effects of adsorption temperature, CO2 concentration, and bed length on process efficiency were evaluated using surface response methodology.