PROGRAMA DE PÓS-GRADUAÇÃO EM QUIMICA - PPGQuim

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    Obtenção e fracionamento de ésteres metílicos de ácidos graxos a partir do óleo de coco ariri (Syagrus cocoides martius)
    (Universidade Federal do Maranhão, 2020-12-09) BASTOS, Fernanda Carneiro; MACIEL, Adeilton Pereira; 929354274-91; http://lattes.cnpq.br/4957262830051547; MACIEL, Adeilton Pereira; 929354274-91; http://lattes.cnpq.br/4957262830051547; CAVALCANTE, Kiany Sirley Brandão Cavalcante; http://lattes.cnpq.br/3810732989135120; ROCHA, Claudia Quintino da; http://lattes.cnpq.br/5609489233382242
    Despite the great diversity of palm trees (Arecaceae) there is still no data on many of them, for example ariri. The ariri is of the Syagrus genus and has fruits composed of oily almonds and its application is mainly restricted to popular use. This work aims to evaluate the ariri coconut almond oil, as to the extraction method and as a raw material for obtaining enriched fractions of methyl esters of fatty acids. Initially, the species used was identified. The extraction of almond oil was performed in cold and hot way, with fruits collected in a dry and rainy season; and analyzed as to the yield and physical-chemical parameters.The esters were obtained by alkaline transesterification, under magnetic stirring at 60 ° C (333, 15 F), 1:18 m / m molar ratio (oil: methanol) and 1% KOH catalyst (% oil mass); for 1 hour. The fractionation of the esters was performed by liquid column chromatography, packed with silica gel 60, mobile phase hexane / ethyl acetate; accompanied by Thin Layer Chromatography and Gas Chromatography coupled to Mass Spectrometer. The species was identified as Syagruscocoides Martius. The extractions proved to be efficient and without significant changes due to the method used. As for the collection period, the oil from fruits obtained in the dry period showed better quality. Several fractions were obtained among them pure fraction of the methyl ester of lauric acid and mixtures containing 2-6 esters, with 62.7–96.95% of the methyl ester of lauric acid. This result accredits coconut ariri as an excellent raw material for obtaining new high purity standards and as a raw material for application in various products.
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    Síntese e caracterização de compósito carbonáceo de magnetita para aplicação como fotocalisador
    (Universidade Federal do Maranhão, 2018-09-28) COSTA, Fernanda Rodrigues Torres da; MACIEL, Adeilton Pereira; 929354274-91; http://lattes.cnpq.br/4957262830051547; MACIEL, Adeilton Pereira; 929354274-91; http://lattes.cnpq.br/4957262830051547; CAVALCANTE, Kiany Sirley Brandão; http://lattes.cnpq.br/3810732989135120; DAMOS, Flávio Santos; http://lattes.cnpq.br/0915687070195770
    In the present work a carbonaceous composite of magnetite obtained from the coconut ariri biomass was prepared by the wet impregnation method with iron chloride III for the degradation of the rhodamine B. The composite was characterized by X-Ray Diffraction), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), X-ray energy dispersion spectroscopy (EDX), Raman Spectroscopy and Thermogravimetric analysis of biomass. The obtained compound presented magnetic characteristics, where such property facilitates the removal of the material in a reaction mixture. With the XRD technique, one can observe the presence of phases referring to a carbonaceous material with phase of magnetite. The infrared spectra confirmed the presence of the vibrations of the main bonds present in the in natura biomass and the obtained composite. The micrographs illustrated a heterogeneous material. The EDX technique shows that the composite is composed primarily of carbon, iron, and oxygen. The RAMAN spectroscopy demonstrates that the composite obtained has characteristics of carbonaceous compound. In the thermal analysis of the biomass, it was observed the main losses of mass, referring to the decomposition of the lignino-cellulosic material, as well as the influence of iron chloride. After characterizing this carbonaceous compound was applied in the degradation of rhodamine B, where the photocatalytic activity was evaluated by light irradiation in rhodamine solution. The photodegradation of the organic dye reached 80% in maximum time of 140 min light irradiation.