Enhancement effect of CaO for N-containing resins chemical-looping gasification: kinetics and products analysis

N-containing resins have been widely applied in the electronics industry and battery field, the waste consisted by N-containing resins will become serious problems in near future. Chemical-looping gasification (CLG) has advantages in pollution control and treatment efficiency, it should be an effective method to manage these waste. However, tar and char generated by resin decomposition is difficult to further decompose. Therefore, the addition of adjuvant is required. In this work, the enhancement effect on syngas generation of CaO as adjuvant for N-containing resins CLG was explored. The typical N-containing resin, polyimide CLG experiments were conducted. Kinetics and product analysis jointly reveal the chemical mechanism of N-containing resin CLG with CaO participation. The addition of CaO reduced the activation energy of polyimide decomposition obviously, resulting in a carbon conversion efficiency greater than 80%. By using the polyimide CLG process, with the assistance of CaO and H₂O, it was possible to produce syngas with a carbon conversion efficiency of 72.4% and an LHV of 9.6 MJ/Nm³ at 900 °C. The enhancement effect on syngas generation of CaO originated from its role in activating C-N/C-O bonds, as well as absorbing acidic species.The presence of active oxygen and calcium oxide during gasification led to improved decomposition efficiency, resulting in the breakdown of molecular skeletons.