Chemical recycling of plastic waste is a promising technological option to facilitate the creation of a circular economy of plastics, in which they can be used as raw material for the production of new plastics. Chemical Looping (CL) technologies can contribute to chemical recycling of plastic waste. CL combustion (CLC) allows processing waste plastic with inherent CO2 capture, generating a pure CO2 stream to be used for new plastic production. CL gasification (CLG) allows syngas production with CO2 capture for chemicals or synthetic fuels production. The objective of the present work is first to select the most promising oxygen carriers, natural and synthetic oxygen, for the combustion and gasification of plastic. This work was carried out in a batch fluidized bed, where different temperatures were evaluated as well as gas evolution during different experimental conditions. Finally, the selected oxygen carriers were evaluated in a continuous unit that can work at 20 kW in CLG mode and 50 kW in CLC mode. Different operation conditions were evaluated: the excess of air considering the air flow in the air reactor, the fuel feeding rate in the fuel reactor and the fuel reactor temperature. Their influence on the gas composition, the tar evolution and other possible pollutants (depending on the plastic used) were evaluated.