Recycling and Characterization of Carton Packaging for the Production of Cellulose Nanofibers and Aluminum Oxide
Carton Packaging, Cellulose Nanofibers, Aluminum Oxide, LDPE, Recycling.
This study focuses on the importance of recycling, especially in the context of carton packaging, as an essential part of seeking sustainable solutions for urban solid waste management. The study material comprises carton packaging, notably the cellulose pulp extracted from these packages, which are composed of layers of paperboard (CB in natura), Low-Density Polyethylene (LDPE), and aluminum (Al). The primary objective of this research is to evaluate the feasibility of separating the elements contained in carton packaging. This involves the application of various chemical treatments to obtain cellulose nanofibers (CNF) from CB in natura, as well as the synthesis of aluminum oxide (Al2O3) based on the extracted Al. Additionally, efficient separation of LDPE is sought based on its volatility properties concerning temperature. Recycling and effective separation of the components of these packages significantly contribute to improving these practices, using both physical and chemical separation methods. For this purpose, the research proposes material recovery techniques aimed at obtaining CNF and Al2O3, with the intention of reducing waste and promoting environmental sustainability. The research involved the application of various chemical treatments on cellulose fibers obtained from carton packaging, resulting in CNF and Al2O3, as well as investigating the behavior of untreated LDPE. The CB in natura and treated fibers (CNF, Al2O3, and LDPE) underwent characterizations through techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TG/DTG/DSC), and Fourier-transform infrared spectroscopy (FTIR). The results revealed chemical modifications in the treated fibers, with a significant increase in crystallinity index: CB in natura (41.08%), treated (49.82%), 4B (56.38%), and CNF (62.65%), with an average diameter of 6-41 nm. Chemical analysis of the fibers showed moisture content (MC%) of 5.73±1.22, ash content (AC%) of 1.66±0.02, extractives content (EC%) of 3.69±0.27, insoluble lignin content (ILC%) of 11.66±0.99, holocellulose content (HC%) of 85.30±0.27, alpha cellulose content (ACC%) of 67.05±0.24, and hemicellulose content (HMC%) of 18.25±0.24. The thermal stability of the samples ranged from 195.22°C to 249.93°C, with discussions on the effects of chemical treatments on the properties of cellulose fibers. Aluminum oxide nanoparticles, with an average diameter of 2 nm, exhibited non-uniform distribution and the presence of crystalline phases (α and γ) confirmed by XRD. LDPE exhibits a melting point with a Tm value of 109.50°C and thermal stability recorded at 76.80°C. This study aims to improve the recycling practices of carton packaging through physical and chemical separation methods. Proposing material recovery techniques to produce cellulose nanofibers and aluminum oxide, reducing waste, and promoting environmental sustainability with higher value-added products.