Comparison of Virgin LDPE and an Industrial Multilayer Plastic Film in a Continuous Pilot-Scale Fluidized-Bed Pyrolysis Reactor

Moreover, the gaseous stream showed components such as CO, CO₂, HCN, and NH₃, suggesting secondary reactions of PA-6. Interestingly, CO was also found with pure LDPE, which was most likely associated with the additives present in the feed. Analysis of both the organic and condensed water fractions revealed that the majority (90 wt %) of formed caprolactam from PA-6 ended up in the condensed water fraction from the steam carrier gas.

Furthermore, other polar components such as carboxylic acids, acetone, and HCN were found in the water phase. Based on elemental analysis, the majority (∼60 wt %) of the analyzed nitrogen in the condensables was found in the water phase, and only 15–23 wt % was found in the organic phase. The use of steam as a carrier gas was shown to scrub the organic pyrolysis product, providing an integrated purification step by removing part of the heteroatom components.

This combined with the use of a scalable fluidized-bed reactor could offer a viable chemical recycling route for hard-to-recycle plastic wastes such as multilayer films, which are not currently efficiently utilized.