Spectroscopic characterization and thermal behavior of baru nut and macaw palm vegetable oils and their epoxidized derivatives

The ability to produce new and renewable, epoxidized Brazilian vegetable oils from baru nut (Dipteryx alata Vogel) and macaw palm (Acrocomia aculeata) oil, using a fast and clean heterogeneous catalytic method, was investigated. The Wijs method and Proton Nuclear Magnetic Resonance (1H-NMR) analysis were utilized, and compared to one another, to calculate the iodine value (IV), average number of double bonds (DBaverage) and fatty acid content, and thus degree of epoxidation, for both vegetable oils. This analysis indicated that alkene conversions of >99% and 95.3% were obtained for baru nut oil and macaw palm oil, respectively; which is an excellent result when compared with some works in literature. The epoxidized Baru nut oil is a solid at room temperature, which was related to the percentage of mono-unsaturated fatty acids present in its structure. Epoxide samples were also analyzed via mid-Infrared Spectroscopy and 13C NMR analysis. Thermogravimetry-differential thermal analysis (TG-DTA) was used to determine the thermal stability of these epoxidized oils. Differential Scanning Calorimetry (DSC) also provided information about their crystallization, melting and solid-solid transition processes

Highly crosslinked polyesters prepared by ringopening copolymerization of epoxidized baru nut and macaw palm oils with cyclic anhydrides

Epoxidised Brazilian vegetable oils obtained from the baru nut (Dipteryx alata Vogel) and the macaw palm (Acrocomia aculeata) react with bioderivable anhydrides (succinic, glutaric, itaconic or citraconic) to give highly crosslinked polyesters. The polymerisation is initiated by a metal-free catalyst system comprising dicyclohexyl urea and bis(triphenylphosphine)iminium chloride. The resulting polymers can be obtained as powders or rubbery disks and are chemically and physically characterised. On treatment with aqueous sodium hydroxide, the polymers degrade to water soluble glycerol and sodium carboxylates

Preparação e estudo termoanalítico dos 2-clorobenzalpiruvatos de alumínio, de gálio, de índio e de escândio no estado sólido

No presente trabalho, os 2-clorobenzalpiruvatos de alumínio, gálio, índio e escândio foram sintetizados, misturando-se soluções aquosas do ligante com as dos respectivos nitratos até total precipitação dos íons metálicos. Os precipitados foram lavados com água destilada até total eliminação dos íons nitratos, filtrados, secos e mantidos em dessecador sob cloreto de cálcio anidro. Na caracterização, verificação da estabilidade e o estudo da decomposição térmica desses compostos foram utilizados as técnicas de análise elementar, espectroscopia de absorção na região do infravermelho, difratometria de raios X pelo método do pó e termogravimetria-analise térmica diferencial simultânea (TG-DTA). Os espectros de absorção na região do infravermelho permitiram sugerir que a coordenação do ligante aos íons metálicos ocorre pelo carboxilato de forma unidentada, formando também ligações em ponte e sem a participação da carbonila cetônica. Os difratogramas de raios X pelo método do pó mostram que todas os compostos sintetizados foram obtidos no estado não cristalino. Os resultados analíticos e termoanalíticos permitiram estabelecer a formula geral M(2-Cl-BP)3.nH2O, onde M= Al, Ga, In, Sc e n= 2; 2; 1,5; 2,5; respectivamente. As curvas TG-DTA simultâneas desses compostos mostram que a desidratação ocorre em uma única etapa, seguida da decomposição térmica sem evidência de formação de compostos anidros estáveis. Essas curvas também mostram que a decomposição térmica ocorre através de duas ou três etapas sobrepostas até 600 ºC, com formação dos respectivos óxidos, Al2O3, Ga2O3, In2O3, e Sc2O3.In the present work, the aluminum, gallium, indium and scandium 2-chlorobenzylidenepyruvates were synthesized by mixing an aqueous solution of the ligand with aqueous solutions of the corresponding metal nitrate, until total precipitation. The precipitates were washed with distilled water, filtered, dried and kept in a desiccator over anhydrous calcium chloride. Elemental analysis, infrared spectroscopy, X-ray powder diffratometry, simultaneous thermogravimetry-differential thermal analysis (TG-DTA) have been used to characterize to verify the thermal stability and to study the thermal decomposition of the synthesized compounds. Infrared spectra, permitted to suggest that the coordination of the ligand to metallic ions occurs by the carboxylate anion as the unidentate form, and also as bridge without the participation of the ketonic carbonyl group. The X-ray powder diffraction patterns showed that all the synthesized compounds were obtained in the amorphous state. From the analytical and thermoanalytical results, the general formula M(2-Cl- BP)3.nH2O can be established, were M= Al, Ga, In, Sc and n= 2; 2; 1.5; 2.5; respectively. The simultaneous TG-DTA curves of these compounds showed that the dehydration occurs in a single followed by the thermal decomposition without evidence of the formation of stable anhydrous compounds. These curves also showed that the thermal decomposition occurs through two or three overlapping steps up to 600 °C with formation of the oxides Al2O3, Ga2O3, In2O3, and Sc2O3, respectively

Síntese, caracterização e estudo do comportamento térmico dos 2-clorobenzalpiruvatos de lantânio (III), lantanídios (III) e de ítrio (III), no estado sólido

Foram sintetizados os compostos de formula geral LnL3.nH2O, no estado sólido em que Ln representa lantânio, lantanídios e ítrio e L é o 2-clorobenzalpiruvato. Esses compostos foram caracterizados por termogravimetria - análise térmica diferencial (TGDTA), calorimetria exploratória diferencial (DSC), difratometria de raios X pelo método do pó, analise elementar, complexometria com EDTA e espectroscopia de absorção na região do infravermelho. As decomposições térmicas desses compostos ocorreram em duas (Ce), quatro (La, Nd, Sm Gd, Tb, Ho-Lu e Y) ou cinco (Pr, Eu e Dy) etapas. A primeira etapa está associada a perdas de moléculas de água de hidratação e a decomposição térmica dos compostos anidros se conclui acima dos 1200ºC com a formação dos respectivos óxidos, CeO2, Pr6O11, Tb4O7 e Ln2O3 (Ln = La, Nd, Sm, Eu, Gd, Dy-Lu e Y). As entalpias de desidratação dos compostos de Pr ao Lu e Y foram: 140,1; 148,2; 221,3; 65,77; 55,63; 86,89; 121,65; 99,80; 109,59; 131,02; 119,78; 205,46 e 83,11 KJ mol-1, respectivamente. Os dados experimentais e teóricos da espectroscopia de absorção na região do infravermelho sugerem uma coordenação bidentada entre o ligante e o íon metálico formando um anel de cinco membros. As curvas TG-DTA, TG/DTG e DSC forneceram informações com relação ao comportamento térmico e a decomposição dos compostos sintetizados. A presença de íons cloreto nos resíduos da decomposição térmica foi verificada por EDX. Os dados de EDX mostraram que a presença de íons cloreto decresce com o aumento do número atômico: ítrio > lantânio > lantanídios.Solid-state compounds of general formula LnL3.nH2O, in wich Ln represents lanthanum, lanthanides and yttrium and L is 2-chlorobenzylidenepyruvate, were synthesized. Chemical analysis, simultaneous thermogravimetry-differential analysis (TGDTA), differential scanning calorimetry (DSC), X-ray powder diffractometry, elemental analysis and infrared spectroscopy were employed to characterize and to study the thermal behaviour of these compounds in dynamic air atmosphere. On heating these compounds decompose in two (Ce), four (La, Nd, Sm Gd, Tb, Ho- Lu and Y) or five (Pr, Eu and Dy) steps. They lose the hydration water in the first step and the thermal decomposition of the anhydrous compounds occurs up to 1200°C with the formation of the respective oxide, CeO2, Pr6O11, Tb4O7 and Ln2O3 (Ln = La, Nd, Sm, Eu, Gd, Dy-Lu and Y) as final residue. The dehydration enthalpies found for Pr to Lu and Y compounds were: 140,1; 148,2; 221.3; 65,77; 55,63; 86,89; 121,65; 99,80; 109,59; 131,02; 119,78; 205,46 and 83,11 kJ mol-1, respectively. The experimental and theoretical infrared spectroscopic data suggested that 2-Cl-BP acts as a bidentate ligand towards trivalent lanthanides and yttrium(III). The TG-DTA, TG/DTG and DSC curves provided previously unreported information concerning the thermal behaviour and thermal decomposition of synthesized compounds. The presence of chloride ions in these residues was also verified by EDX investigations. The EDX data also show that the presence of chloride ions decrease with the increase of the atomic number.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Synthesis, characterization and thermal behaviour of solid state compounds of 2-chlorobenzylidenepyruvate with trivalent aluminium, gallium, indium and scandium metals

Foram preparados compostos sólidos M(2-Cl-BP)3.nH2O, onde 2-Cl-BP é o ânion 2-clorobenzalpiruvato e M representa os íons metálicos trivalentes: alumínio, gálio, índio e escândio. Esses compostos foram caracterizados e estudados utilizando-se as técnicas de difração de raios X, pelo método do pó, espectroscopia de absorção na região do infravermelho e termogravimetria-análise térmica diferencial simultâneas (TG-DTA). Os resultados permitiram obter informações com respeito a estequiometria, cristalinidade, estabilidade e decomposição térmica.Solid state compounds M-2-Cl-BP, where 2-Cl-BP is 2-chlorobenzylidenepyruvate and M represents Al, Ga, In, and Sc were prepared. X-ray powder diffractometry, infrared spectroscopy and simultaneous thermogravimetry-differential thermal analysis (TG-DTA), have been used to characterize and to study the thermal behavior of these compounds. The results provided information concerning the stoichiometry, crystallinity, thermal stability and thermal decomposition of the compounds.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Synthesis, characterization and thermal studies of solid state 4-methylbenzylidenepyruvate of some trivalent metal ions

Os 4-metilbenzalpiruvatos de Al(III), Ga(III), In(III) e SC(III), foram sintetizados no estado sólido. Na caracterização e estudo do comportamento térmico desses compostos foram utilizados a complexometria, difratometria de raios X pelo método do pó, espectroscopia na região do infravermelho e termorgravimetria-análise térmica diferencial simultâneas (TG-DTA). Os resultados forneceram informações com respeito a estequiometria, cristalinidade, estabilidade e decomposição térmica desses compostos.Solid state compounds of 4-methylbenzylidenepyruvate with Al(III), Ga(III), In(III) and Sc(III) have been synthesized. Complexometry, X-ray powder diffractometry, infrared spectroscopy and simultaneous thermogravimetry-differential thermal analysis (TG-DTA) have been used to characterize and to study the thermal behavior of these compounds. The results provided information concerning the stoichiometry, crystallinity, thermal stability and thermal decomposition of these compounds.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Opportunities for the Use of Brazilian Biomass to Produce Renewable Chemicals and Materials

This review highlights the principal crops of Brazil and how their harvest waste can be used in the chemicals and materials industries. The review covers various plants; with grains, fruits, trees and nuts all being discussed. Native and adopted plants are included and studies on using these plants as a source of chemicals and materials for industrial applications, polymer synthesis, medicinal use and in chemical research is discussed. The main aim of the review is to highlight the principal Brazilian agricultural resources; such as sugarcane, oranges and soybean, as well as secondary resources, such as andiroba brazil nut, buriti and others, which should be explored further for scientific and technological applications. Furthermore, vegetable oils, carbohydrates (starch, cellulose, hemicellulose, lignocellulose and pectin), flavones and essential oils will be described as well as their potential applications

Synthesis and thermal studies of solid state 2-chloro-benzylidenepyruvic acid and its compounds with sodium, aluminium (III), gallium (III) and indium (III) cations

A síntese do 2-clorobenzalpiruvato de sódio e seu respectivo ácido, bem como compostos binários, compostos binários junto com seu respectivo ácido ou hidroxo-2-clorobenzalpiruvato de alumínio (III), gálio (III) e de índio (III), foram isolados. Na caracterização e estudo do comportamento térmico desses compostos foram utilizados a termogravimetria, termogravimetria derivada (TG/DTG), termogravimetria-analise térmica diferencial simultânea (TG-DTA), difratometria de raios X pelo método do pó e análise química. Os resultados forneceram informações com respeito a estequiometria, cristalinidade, estabilidade e decomposição térmica.The synthesis of sodium 2-chlorobenzylidenepyruvate and its corresponding acid as well as binary, binary together with it's acid or hydroxo-2-chorobenzylidenepyruvate of aluminium (III), gallium (III) and indium (III), were isolated. Chemical analysis, thermogravimetry, derivative thermogravimetry (TG/DTG), simultaneous thermogravimetry-differential thermal analysis (TG-DTA) and X-ray powder diffractometry have been employed to characterize and to study the thermal behaviour of these compounds. The results provided information concerning the stoichiometry, crystallinity, thermal stability and thermal decomposition.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq