Actionable insights into hazard mitigation of typical 3D printing waste via pyrolysis

Ziting Lin; Jingyong Liu; Haiming Cai; Fatih Evrendilek; Chuanghai Zhu; Fanjin Liang; Wenxiao Huang; Weixin Li; Chao He; Chunxiao Yang; Zuoyi Yang; Sheng Zhong; Wuming Xie; Yao He

doi:10.1016/j.jhazmat.2023.132414

Actionable insights into hazard mitigation of typical 3D printing waste via pyrolysis

J Hazard Mater. 2023 Oct 15:460:132414. doi: 10.1016/j.jhazmat.2023.132414. Epub 2023 Aug 26.

Authors

Ziting Lin¹, Jingyong Liu², Haiming Cai³, Fatih Evrendilek⁴, Chuanghai Zhu¹, Fanjin Liang¹, Wenxiao Huang⁵, Weixin Li⁵, Chao He⁶, Chunxiao Yang⁷, Zuoyi Yang¹, Sheng Zhong¹, Wuming Xie¹, Yao He¹

Affiliations

¹ School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China.
² School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China. Electronic address: Liujy@gdut.edu.cn.
³ School of Environment and Energy, South China University of Technology, Guangzhou 510006, China.
⁴ Department of Electrical & Computer Engineering, College of Engineering, Boston University, Boston, MA 02215, United States.
⁵ Key Laboratory of Radioactive and Rare Scattered Minerals, Ministry of Natural Resources, Guangdong Provincial Institute of Mining Applications, Guangdong 512026, China.
⁶ Faculty of Engineering and Natural Sciences, Tampere University, Korkeakoulunkatu 8, 33720 Tampere, Finland.
⁷ School of Analysis and Test Center, Guangdong University of Technology, Guangzhou 510006, China.

PMID: 37677970
DOI: 10.1016/j.jhazmat.2023.132414

Abstract

3D printing waste (3DPW) contains hazardous substances, such as photosensitizers and pigments, and may cause environmental pollution when improperly disposed of. Pyrolysis treatment can reduce hazards and turn waste into useful resources. This study coupled thermogravimetric (TG), TG-Fourier transform infrared spectroscopy-gas chromatography/mass spectrometry, and rapid pyrolysis gas chromatography/mass spectrometry analysis to evaluate the pyrolytic reaction mechanisms, products, and possible decomposition pathways of the three typical 3DPW of photosensitive resin waste (PRW), polyamide waste (PAW), and polycaprolactone waste (PCLW). The main degradation stages of the typical 3DPW occurred at 320-580 °C. The most appropriate reaction mechanisms of PRW, PAW and PCLW were D1, A1.2 and A1.5, respectively. The main pyrolysis processes were the decomposition of the complex organic polymers of PRW, the breaking of the NH-CH₂ bond and dehydration of -CO-NH- of PAW, and the breaking and reorganization of the molecular chains of PCLW, mainly resulting in toluene (C₇H₈), undecylenitrile (C₁₁H₂₁N), tetrahydrofuran (C₄H₈O), respectively. Unlike the slow pyrolysis, the rapid pyrolysis produced volatiles consisting mainly of phenol, 4,4'-(1-methylethylidene)bis- (C₁₅H₁₆O₂) for PRW; 1,10-dicyanodecane (C₁₂H₂₀N₂) for PAW; and ɛ-caprolactone (C₆H₁₀O₂) for PCLW. These pyrolysis products hold great potential for applications. The findings of the study offer actionable insights into the hazard reduction and resource recovery of 3D printing waste.

Keywords: 3D printing waste; Master-plots method; Pyrolysis; TG-FTIR-GC/MS; Volatile products.