Recovery and Characterization of Nano-Ag-graphene-TiO2: Active Compound from Polylactic Acid (PLA)-Based Film

The recover of the used Ag-graphene-TiO2 composite extracted from the polylactic acid (PLA) film and its characterization in comparison with the newly prepared composite was the aim of this study. The proposed recovery procedure will reduce the amount of inorganic nanostructured material released into the environment as used food packaging. Morpho-structural, environmental and photocatalytical characteristics of Ag-graphene-TiO2 composite recovered from an used PLA-based film in comparison with those of the new prepared composite are reported. The recovered Ag-graphene-TiO2 composite displayed color, consistence, appearance, homogeneity and dispersion of nano-Ag similar with the new prepared compound. The FTIR spectroscopy showed the presence of Ti–O–C bonds suggesting the cross-linking between TiO2 and graphene both in new and recovered composite. The gap energy (Eg) of the recovered composite is 1.4 times and 2.3 times lower than that of new composite and TiO2, respectively. The anatase`s content decreased by 70% during the recovering, while that of rutile rised with the same magnitude. The photocatalytic activity of the recovered composite decreased only by 30% in comparison with the new composite. Additionally, the Life-Cycle Analysis (LCA) showed that the recovering procedure had a considerably lower environmental impact than the preparation of the new composite in terms of human health, ecosystem quality, climate change and resources. In conclusion, the recovering of the nanostructed composites from the active PLA-based films should be promising way to imporve the waste management.