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Chitin is the main product obtained from the processing of crustacean shells. This biopolymer and its derivative, chitosan, have aroused great commercial interest because of the possibilities of applications they have. The management of these wastes and by-products generated in the steps of obtaining processes can be considered a biorefinery model. The implementation of plants for chitin and chitosan extraction is a challenge, since the production demand must be met without causing harm to the environment. A wide variety of chitosan with different physico-chemical properties can be obtained by varying the reaction conditions. These properties depend on the origin of the raw material, its average degree of deacetylation average distribution of the acetyl groups along the backbone and its average molecular weight. Chitosan commercial providers generally do not mention the origin of the raw material and few or no information is provided about the processing. Therefore, the characteristics and reactivity of the final product may vary generating non-reproducible results. The biomass coming from the fishing industry tailings shrimp Cananéia SP region was used in the present study. Samples of α-chitin were obtained by two different procedures: the first, P1, the shrimp shells after passing through the pretreatment (rinsing, drying and grinding) were deproteinized for removal of proteins in diluted sodium hydroxide (NaOH) in concentrations 2%, 5% and 10% and demineralized in hydrochloric acid (HCl) to 20% (v/v) to remove carbonates; in the second procedure, P2, these steps were reversed. The resulting biomass was deacetylated with sodium hydroxide concentrated at 30%, 40% and 50% in times ranging from 2 to 6 hours. The main physicochemical properties of chitosan samples obtained were determined using Fourier transform infrared spectroscopy (FT-IR) to determine the average degree of acetylation, DA ̅̅ ̅̅ , and the acid-base titration technique measured by conductimetry was used to compare the results of chitosan; capillary viscometry to determine the viscosimetric average molecular weight, MV ̅̅ ̅̅ , and X-ray diffraction (XRD) to evaluate the average degree of crystallinity, ?̅?. In addition, scanning electron microscopy (SEM) were employed for morphological analyzes of the obtained materials and wavelength dispersion Xray fluorescence (WDXRF) for chemical analysis of chitosan. The DA ̅̅ ̅̅ and ?̅? of the samples decreased as the treatment became stronger, while MV ̅̅ ̅̅ increased. Procedure 2 was the most feasible to eliminate the depigmentation step because gave clearer and easier samples spraying. Key-words: Chitin, chitosan, obtaining processes, physicochemical characterization. Sumário RESUMO  5 ABSTRACT  7 LISTA DE TABELAS  11 LISTA DE FIGURAS  13 LISTA DE SIGLAS E ABREVIATURAS  16 LISTA DE UNIDADES  18 1 INTRODUÇÃO  19 2 OBJETIVO  24 3 REVISÃO DA LITERATURA E ESTADO DA ARTE  25 3.1 Quitina  25 3.2 Quitosana  28 3.3 Aplicações  30 3.4 Principais propriedades da quitina e quitosanas  34 3.4.1 Grau Médio de Cristalinidade (X)  35 3.4.1.1 Estrutura cristalina da quitina36 3.4.1.2 Estrutura cristalina da quitosana39 3.4.1.3 Difração de raios X42 3.4.2 Grau Médio de Desacetilação (GD)  44 3.4.2.1 Espectroscopia na região do infravermelho (IV)48 3.4.2.2 Método de titulação ácido-base54 3.4.3 Massa Molecular Média (M)  55 4 MATERIAIS E MÉTODOS  61 4.1 Fluxograma de Trabalho  61 4.2 Materiais  62 4.3 Obtenção das amostras de quitina  62 4.4 Obtenção das amostras de quitosanas  65 4.5 Caracterização das amostras de α-quitina e quitosanas .... 67 4.5.1 Análise morfológica por Microscopia Eletrônica de Varredura  67 4.5.2 Percentual de material insolúvel nas amostras de quitosanas  67 4.5.3 Determinação do grau médio de cristalinidade por difração de raios X   68 4.5.4 Determinação do grau médio de acetilação por espectroscopia na região do infravermelho  68 4.5.5 Determinação do grau médio de desacetilação das amostras de quitosanas por titulação condutimétrica  68 4.5.6 Determinação da massa molecular média das amostras de quitosanas por viscosimetria capilar  69 4.5.7 Análise química das amostras de quitosanas por Espectroscopia de Fluorescência de raios X por dispersão de comprimento de onda  69 4.5.8 Análise estatística 72 5 RESULTADOS E DISCUSSÕES  71 6 CONCLUSÕES  107 7 REFERÊNCIAS  109

Processos de obtenção e caracterização físico-química de quitinas e quitosanas extraídas dos rejeitos da indústria pesqueira da região de Cananéia - SP