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Cigarette butts are one of the most common types of litter all around the world. This waste when disposed of in the environment pose a major threat to living organisms and ecosystem health. Cigarette butts are mainly made of cellulose acetate (2.45 substitution) that biodegrades slowly and can take up to 18 months to break down under normal litter conditions. Cellulose acetate is a valuable polymer that can be used for a great variety of applications. In this communication, we present the results from an ongoing study addressed to value cigarette butt waste based on the recovery of the cellulose acetate by a methodology that includes several solid-liquid extractions and a chemical precipitation. For that purpose three samples of cigarette butts were prepared and they were extracted with 5% (w/v) NaCl aqueous solution, 5% (w/v) NaAc aqueous solution or 0,02% (w/v) H2SO4 aqueous solution. After that, they were further extracted with absolute ethanol and diethyl ether. The cleaned butts were suspended in acetone and distilled water was added until a white precipitate of cellulose acetate was formed. Cellulose acetate was characterised by FTIR-ATR and its melting point. Extracts were analized by ICP-MS and GC-MS.

In this research, a new generation of ternary nanocomposites based on poly(ethylene terephthalate) (PET), phosphorylated chitosan and surface modified alumina nanoparticles were fabricated in four steps. The phosphorylation process was targeted for the insertion of phosphorus moieties as a flame retardant agent in the final PET nanocomposite. Likewise, environmentally friendly nano-alumina was used for PET matrix to improve the thermal properties of PET in collaboration with organic anchored phosphorus moieties. Alternatively, the presence of bio-safe modified alumina nanoparticles in combination with phosphorylated chitosan simultaneously improved the antibacterial activity and thermal properties of the PET matrix. Furthermore, the effects of the phosphorylated chitosan and alumina nanoparticles on the morphology and thermal properties of nanocomposites were inspected by different approaches. The structure and distribution of the nanoscale particles in PET were analyzed by scanning electron microscopy. In addition, differential scanning calorimetry and thermogravimetric analyses were used for the in-depth evaluation of the thermal properties of prepared nanocomposites. Prepared nanocomposites showed better growth inhibition activities against Escherichia coli bacteria compared to the PET and PET/phosphorylated chitosan samples. Also, the thermal characteristics of prepared nanocomposites were considerably improved.

Cross-coupling reactions leading to carbon–heteroatom bonds yield compounds that attract substantial interest due to their role as structural units in many synthetic protocols for bioactive and natural products. Therefore, many research works aim at the improvement of heterogeneous catalytic protocols. We have studied the use of magnetite nanoparticles and solid base compounds in organic synthetic reactions in carbon–heteroatom bond formation because they can be flocculated and dispersed, and reversibly controlled by applying a magnetic field. In this work, we have developed an efficient and simple synthetic approach for the C–O/C–N cross-coupling reaction under ligand-free conditions by using CuI as a catalyst and KF/Fe3O4 as a base. We performed the nucleophilic aromatic substitution of electron-deficient aryl halides and phenols. It was found that both the solvent nature and the base have a profound influence on the reaction process. This approach affords good to excellent yields of arylated products. KF/Fe3O4 displayed convenient magnetic properties and could be easily separated from the reaction using a magnet and recycled several times without significant loss of catalytic activity. This method has been successfully investigated for the Ullmann coupling reaction.

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