Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2017-08-28T19:40:42Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) elisiane_dantas_rocha.pdf: 1578502 bytes, checksum: 6377ba5382224c4f4ab2f117cb851a38 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2017-08-30T18:46:12Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) elisiane_dantas_rocha.pdf: 1578502 bytes, checksum: 6377ba5382224c4f4ab2f117cb851a38 (MD5) / Made available in DSpace on 2017-08-30T18:46:12Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) elisiane_dantas_rocha.pdf: 1578502 bytes, checksum: 6377ba5382224c4f4ab2f117cb851a38 (MD5) Previous issue date: 2016 / A glicerina bruta, obtida de forma direta no processo de produ??o de biodiesel, ? um insumo abundante e, devido a impurezas, ainda ? pouco atrativa para ser trabalhada como precursor em escala industrial. Apesar da sua aplica??o agr?cola, na fertiliza??o do solo ainda ter recebido pouca aten??o, a glicerina bruta tem potencial de utiliza??o na agricultura, sendo que a associa??o com outros tipos de materiais pode ampliar sua utiliza??o no mercado. O presente trabalho teve como objetivo sintetizar e caracterizar novos produtos a partir de glicerina e ?cido h?mico, para uso na agricultura. Os produtos sintetizados a partir de rea??o de esterifica??o entre glicerina purificada ou bruta, proveniente do processo de produ??o de biodiesel met?lico de ?leo de am?ndoa de maca?ba, utilizando hidr?xido de pot?ssio como catalisador, e ?cido h?mico foram obtidos na forma de p?, de colora??o preta. Os produtos foram caracterizados por espectroscopia no infravermelho com transformada de Fourier (FTIR), an?lise elementar, an?lise de fluoresc?ncia de raios-X, titula??o potenciom?trica e an?lise t?rmica. A modifica??o estrutural do ?cido h?mico por glicerina purificada (AH_GP) e glicerina bruta (AH_GB) originou produtos com caracter?sticas espec?ficas, devido ao tempo de rea??o e os diferentes tipos de glicerina utilizados como mat?ria-prima. Os produtos mostraram modifica??es de grupos carbox?licos em grupos ?ster devido ? s?ntese de esterifica??o, que proporcionou uma forma de modular a quantidade de grupos funcionais presentes na estrutura. A utiliza??o de glicerina bruta no processo promoveu a forma??o de diferentes tipos de ?steres, dependendo do tempo de rea??o. Com um tempo de rea??o curto, ocorreu a forma??o de ?steres de glicerol e ?steres met?licos, devido ? presen?a de metanol residual do processo de produ??o de biodiesel. Quando o tempo de rea??o foi aumentado, os ?steres met?licos foram convertidos em ?steres de glicerol, por transesterifica??o, o que foi confirmado por FTIR e an?lise elementar. Os produtos sintetizados apresentaram ganho de estabilidade t?rmica, o que indicou maior capacidade para reter ?gua comparado ao ?cido h?mico comercial. Dos resultados obtidos pela an?lise de fluoresc?ncia de raios-X, notou-se que os novos produtos cont?m enxofre e pot?ssio. Avaliou-se a capacidade de adsor??o de nitrog?nio amoniacal por amostras dos produtos. Os resultados referentes ? adsor??o de NH4+ foram submetidos ao teste t de Student com n?vel de confian?a de 90%. Os produtos sintetizados t?m capacidade de adsorver nitrog?nio em altas propor??es mesmo com a mudan?a na estrutura qu?mica dos produtos que, ap?s modifica??o tiveram diminui??o na quantidade absoluta de s?tios ativos fortemente ?cidos. / Disserta??o (Mestrado) ? Programa de P?s-gradua??o em Biocombust?veis, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2016. / The crude glycerin obtained directly in the biodiesel production process, is an abundant raw material, and due to impurities, it is still unattractive to be worked as a precursor on an industrial scale. Despite its agricultural application, soil fertilization still has received little attention, crude glycerin has a potential for use in agriculture and the association with other types of materials can expand its use in the market. This study aimed to synthesize and characterize new products from glycerin and humic acid for use in agriculture. The products synthesized via esterification reaction between purified or crude glycerin, obtained from the production of methyl biodiesel from macauba almond oil, using potassium hydroxide as a catalyst, and humic acid were obtained as a powder of black color. The products were characterized by infrared spectroscopy with Fourier transform (FTIR), elemental analysis, fluorescence X-ray analysis, thermal analysis and potentiometric titration. The structural modification of humic acid by purified glycerin (AH_GP) and crude glycerin (AH_GB) originated products with specific characteristics that varied with the reaction time and the types of glycerin used as a raw material. Transformation carboxylic groups into ester groups was observed, which provided a way to modulate the number of functional groups present in the structure. The use of crude glycerin in the process promoted the formation of different types of esters depending on the reaction time. With a short reaction time, occurred the formation of glycerol esters and methyl esters that resulted from the presence of residual methanol from the biodiesel production process. When the reaction time was increased, the methyl esters were converted to glycerol esters by transesterification, which was confirmed by elemental analysis and FTIR. The products synthesized had greater thermal stability than humic acid, which indicated a higher water-holding capacity than that to commercial humic acid. Results obtained by fluorescence X-ray analysis, it has noticed that the new products contain sulfur and potassium. It was evaluated the ability of ammonium ion by adsorption product samples. The results of the adsorption of NH4+ were submitted to the Student t test with a confidence level of 90. The synthetized products have a capacity adsorb nitrogen at high rates even with the change in their chemical structures that resulted in a reduction in the absolute quantity of strongly acid active sites after modification.