Characteristics of pollutant generation from 3D-printed photocured waste combustion.

With the rapid advancement of photopolymerization-based 3D printing technology, the volume of PCW has experienced a sharp increase. The potential environmental ramifications of PCW disposal demand careful consideration, especially given its current practice of being incineration alongside MSW. In this study, the TG-MS/FTIR system was carried out to probe the thermogravimetric characteristics and volatile byproducts during combustion. Various product compositions resulting from different mixing ratios of PCW incineration with MSW were investigated. It was observed that fluorene (C13H10) and triphenylene (C18H12) produced by PCW combustion 0.52 mg/g and 0.43 mg/g respectively, which are twice as abundant as those generated from normal plastic. When PCW incineration along with MSW, compounds such as naphthalene (C10H8), cyclohexane (C6H12), and heptane (C7H16) were generated in concentrations of 1.25 mg/g, 1.05 mg/g, and 0.95 mg/g respectively, which are at least twice as much as with MSW incineration alone. The incineration of PCW with rubber and textiles resulted in the production of 2.34 mg/g to 3.76 mg/g more PAHs compared to PCW combustion alone. The incineration of PCW with paper resulted in the production of 3.12 mg/g to 5.15 mg/g more heptane, nonane, cyclohexane, pyrene, and anthracene than PCW combustion alone. Incineration of PCW with wood proved to be the cleanest method, with product contents primarily below 0.10 mg/g. When incinerated with food residues or normal plastic, most of the product content remained below 0.05 mg/g. Considering the environmental pollution resulting from PCW combustion, the disposal of PCW warrants careful consideration and management.

Pyrolysis properties and kinetics of photocured waste from photopolymerization-based 3D printing: A TG-FTIR/GC-MS study.

The emerging photopolymerization-based 3D printing industry has led to a growing concern for the disposal of photocured waste (PCW), which is inevitably generated during the life cycle of photopolymerization-based 3D printing. In order to shed light on suitable thermochemical treatment and utilization approaches of PCW, this work comprehensively investigated the properties and kinetics during PCW pyrolysis via TG-FTIR/GC-MS analysis. The results demonstrated that the main decomposition of PCW sample happened in the range 320-550 °C with a total weight loss of 93.34 wt%. According to the result of four kinetic models, the activation energy of PCW sample was approximately 228.58-245.05 kJ/mol. Finally, the FTIR and GC-MS results manifested that the main components of volatiles released at different heating rates were the same. The volatiles mainly include (S)-(+)-2-hydroxy-2-phenylprop, benzaldehyde, benzophenone (photo-initiator), benzoic acid, benzoylformic acid etc., which have a multitude of potential applications. However, these volatiles produced by PCW pyrolysis have a certain toxicity and potential hazard. This study demonstrates insightful fundamentals for thermochemical disposal of PCW, which appears to be potentially valuable with the rapid development of the photopolymerization-based 3D printing industry.