Abstract In the present work, the depolymerization of polyethylene terephthalate (PET) was performed by the method of glycolysis with ethylene glycol. The process was carried out using a factorial design in the Box-Behnken optimization model, using a response surface methodology (RSM) in which three factors (time, temperature and mass ratio of ethylene glycol) were studied in three levels of variation (- 1, 0, +1) with two replicates of the center point, totalizing 15 experiments for which the yield of bis (2-hydroxyethyl) terephthalate (BHET) monomers formed in the process was chosen as response. In parallel, the Arrhenius kinetic test was used to determine the apparent activation energy (Ea) for the 1-butyl-3-methylimidazole trichlorozincate ([Bmin]ZnCl3) - catalyst used in the depolymerization process. The products of glycolysis obtained were characterized by spectroscopic techniques (FTIR), (1 H and 13C NMR), thermal analyses (TGA) and (DSC) and Mass Spectrometry LC-MS/MS hybrid Quadrupole-Orbitrap.

Abstract In hybrid cultivated form, Dendranthema grandiflorum (Ramat.) Kitam., Asteraceae, flowers (Chrysanthemum morifolium Ramat.) were utilized in the production of extracts, which were analyzed for larvicidal activity against Aedes aegypti third instar larvae. Methanol and dichloromethane extracts showed LC50 values of 5.02 and 5.93 ppm, respectively. Using GC–MS, phytochemical analyses of the dichloromethane extract showed the presence of triterpenoids and fatty acids, while flavonoids and caffeoylquinic acids were shown to occur in the methanol extract by ESI Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (ESI-FT-ICR-MS). Triterpenoids and fatty acids are well known insecticidal compounds. From this study, it can be concluded that D. grandiflorum grown for floriculture, as an agribusiness, can have additional applications as raw material for the production of insecticidal products.

Drug trafficking and the introduction of new drugs onto the illicit market are one of the main challenges of the forensic community. In this study, the chemical profile of a new designer drug, 2-(4-iodine-2,5-dimethoxyphenyl)-n-[(2-methoxyphenyl)methyl]etamine or 25I-NBOMe was explored using thin layer chromatography (TLC), ultraviolet-visible spectrophotometry (UV-Vis), attenuated total reflection with Fourier transform infrared spectroscopy(ATR-FTIR), gas chromatography mass spectrometry (GC-MS) and electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FT-ICR MS). First, the TLC technique was effective for identifying spots related to 25C-, 25B- and 25I-NBOMe compounds, all with the same retention factor, Rf ≈ 0.50. No spot was detected for 2,5-dimethoxy-4-bromoamphetamine, 2,5-Dimethoxy-4-chloroamphetamine or lysergic acid diethylamide compounds. ATR-FTIR preserved the physical-chemical properties of the material, whereas GC-MS and ESI-MS showed better analytical selectivity. ESI(+)FT-ICR MS was used to identify the exact mass (m/z428.1706 for the [M + H]+ ion), molecular formula (M = C18H22INO3), degree of unsaturation (DBE = 8) and the chemical structure (from collision induced dissociation, CID, experiments) of the 25I-NBOMe compound. Furthermore, the ATR-FTIR and CID results suggested the presence of isomers, where a second structure is proposed as an isomer of the 25I-NBOMe molecule.

Neste trabalho foi desenvolvida uma nova metodologia de reciclagem química do poli(tereftalato de etileno) grau garrafa pós-consumo, PETpc, através da reação de despolimerização em meio alcalino (solução de hidróxido de sódio, NaOH, de 7,5 mol L-1 a 100 ºC) e como catalisador o tensoativo catiônico brometo de hexadeciltrimetrilamônio, CTAB (1 × 10-2 mol L-1). A presença de CTAB aumentou o rendimento da reação em cerca de 85% e reduziu o tempo reacional de 6 para 2 h, quando utilizado em mistura NaOH/CTAB na proporção de 4:1 (% v/v) com 2 g de PETpc. O produto final, o monômero ácido tereftálico, TPA, foi caracterizado por análise termogravimétrica, calorimetria diferencial varredura, espectroscopia na região do infravermelho com transformada de Fourier e espectrometria de massas. Os resultados foram comparados com os da matéria-prima, PETpc. Além disso, o catalisador CTAB permaneceu no meio reacional (fase aquosa), sem interferir no processo de purificação do TPA.

In this work, a new analytical methodology has been developed for the chemical recycling of post-consumption bottle-grade poly(ethylene terephthalate), PETpc through depolymerization reaction in alkaline solution (NaOH solution of 7.5 mol L-1 at 100 ºC), using the surfactant cetyl trimethyl ammonium bromide (CTAB, 1 × 10-2 mol L-1) as catalyst. The presence of CTAB increased the reaction performance by ca. 85%, while the reaction time was decreased from 6 to 2 h when the mixture NaOH/CTAB was used in a proportion of 4:1 (% v/v) with 2 g of PETpc. The final product, the monomer terephthalic acid (TPA), was characterized by thermogravimetry analysis, differential scanning calorimetry, Fourier transform infrared spectroscopy and mass spectrometry. The results were compared with those for the raw material, PETpc. Furthermore, the catalyst CTAB remained in the alkaline environment (aqueous phase), without interfering with the TPA purification process.