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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Oxida??o da parede celular da microalga Chlamydomonas sp. para extra??o de lip?dios e avalia??o da sua qualidade para s?ntese de biodiesel

Kramer, Carlos Augusto Cabral 09 March 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-07-03T12:42:01Z No. of bitstreams: 1 CarlosAugustoCabralKramer_DISSERT.pdf: 3674758 bytes, checksum: d133a4aaae2ac30829b112d425bcac3b (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-07-06T13:03:22Z (GMT) No. of bitstreams: 1 CarlosAugustoCabralKramer_DISSERT.pdf: 3674758 bytes, checksum: d133a4aaae2ac30829b112d425bcac3b (MD5) / Made available in DSpace on 2017-07-06T13:03:22Z (GMT). No. of bitstreams: 1 CarlosAugustoCabralKramer_DISSERT.pdf: 3674758 bytes, checksum: d133a4aaae2ac30829b112d425bcac3b (MD5) Previous issue date: 2017-03-09 / Ag?ncia Nacional do Petr?leo - ANP / A produ??o de microalgas para fins energ?ticos tem se tornado um caminho alternativo ? industria do petr?leo por oferecer biocombust?veis renov?veis como o bio?lcool, bio-?leo e o biodiesel. Este ?ltimo ? produzido atrav?s da rea??o de transesterifica??o do material lip?dico que em geral as microalgas produzem naturalmente. Contudo, uma das grandes dificuldades na produ??o do biodiesel de microalgas em grande escala ? a aus?ncia de m?todos eficientes e pouco onerosos para extra??o de lip?dios. Assim, o presente trabalho estudou a efici?ncia da oxida??o da parede celular da microalga do g?nero chlamydomonas sp. com per?xido de hidrog?nio (H2O2) na extra??o de lip?dios, avaliando tamb?m os impactos na qualidade dos lip?dios extra?dos. Percebendo que aumento da concentra??o de H2O2 promove um aumento de 60% no rendimento lip?dico, um indicativo da facilita??o do rompimento da parede celular, que foi comprovado pelo perfil termogravim?trico da biomassa residual e pela mudan?a do formato da c?lula por microscopia ?ptica. Por?m, percebeu-se que os par?metros de qualidade diminu?ram ap?s aplica??o do m?todo, provocando um aumento dos ?ndices de acidez e de per?xidos org?nicos, al?m de uma queda no ?ndice de iodo. Contudo, o perfil espectrosc?pico na regi?o de infravermelho do material lip?dico extra?do com e sem a??o oxidante praticamente s?o id?nticos, indicando que a diminui??o dos par?metros de qualidade n?o afeta significantemente os principais grupos funcionais que comp?e os extratos. O material lip?dico obtido ap?s uso do m?todo oxidativo foi transesterificado, ou seja, convertido em biodiesel, atingindo convers?es a cima de 96% comprovadas via an?lise de cromatografia gasosa. / The production of microalgae for energy purposes has become an alternative route to the oil industry by offering renewable biofuels such as bioethanol, bio-oil and biodiesel. The biodiesel is produced by transesterification of the lipid material and in general cases microalgae produce lipids naturally. However, one of the great difficulties in the production of biodiesel from microalgae on a large scale is the lack of efficient methods and inexpensive for lipid extraction. Thus, this paper studied the cell wall oxidation efficiency of microalgae of the genus Chlamydomonas sp. with hydrogen peroxide (H2O2) in the extraction of lipids, also assessing the impact on the quality of the extracted lipids. The increase H2O2 concentration promotes an increase of 60% in lipid yield, indicative of facilitating the disruption of the cell wall, which was proved by thermogravimetric profile of residual biomass and the change of the cell by optical microscopy. However, it was noted the quality parameters decreases after application of the method, generating higher acid numbers and organic peroxides, besides a decrease in iodine content. However, the spectroscopic profile in the infrared region of the lipid extracted material with and without oxidizing action are almost identical, indicating that the decrease of the quality parameters does not significantly affect the major functional groups belonging extracts. The lipid material obtained after use of the oxidative method was completely transesterified, that is, converted into biodiesel, reaching conversions above 96% proven by gas chromatography analysis.

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