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In dieser Arbeit wird das neue Prinzip der „Selbstinkompatiblen Lösungsmittel“ vorgestellt. Es wird theoretisch abgeleitet, dass eine Mischung aus zwei Substanzen mit ungünstigen Wechselwirkungen bereitwillig eine weitere Substanz aufnehmen sollte, die diese ungünstigen Wechselwirkungen durch Verdünnen vermindert. Dies sollte umso stärker ausgeprägt sein, je ungünstiger die Wechselwirkungen zwischen den beiden ersten Substanzen sind. Da sich jedoch Substanzen mit sehr ungünstigen Wechselwirkungen physikalisch nicht mischen, entstand die Idee, diese Substanzen durch eine kovalente Bindung aneinander zu binden. Ein solches Molekül, das aus zwei inkompatiblen Hälften besteht, wird im Folgendem Selbstinkompatibles Lösungsmittel genannt. Die in dieser Arbeit gewählten Substanzen zeigen mäßige Inkompatibilität, deshalb ist ein Vergleich zwischen einfachen physikalischen Mischungen und kovalent verknüpften Molekülhälften noch möglich. Dieses Prinzip wird für binäre und ternäre Mischungen quantitativ berechnet und experimentell in drei Serien von Experimenten bestätigt: i) unter Verwendung von Lösungskalorimetrie und Bestimmung der Wechselwirkungsparameter zwischen Komponente 3 und einer bereits hergestellt physikalischen binären Mischung aus Komponente 1 und 2, ii) unter Verwendung von Lösungskalorimetrie und Bestimmung der Wechselwirkungsparameter zwischen Komponente 3 und den selbstinkompatiblen Losungsmitteln, die den in (i) gewählten Mischungen entsprechen und iii) aus der Sättigungslöslichkeit der Komponente 3 in den entsprechenden selbstinkompatiblen Lösungsmitteln. In diesen drei verschiedenen Messserien wird stets der gleichen Trend beobachtet: Die Selbstinkompatibilität eines Lösungsmittels begünstigt den Lösevorgang. / In this thesis a new principle of Self Incompatible Solvent is introduced. It is shown theoretically that a preexisting mixture of two substances (compound 1 and 2) with unfavorable interactions will readily dissolve a third compound because it diminishes the unfavorable interaction between the compound 1 and 2 by dilution. This behavior should be the stronger the more unfavorable the interactions between compound 1 and 2 are. However, substances with strong unfavorable interactions will not mix. Therefore the idea pursued here is to enforce the desired preexisting mixture for example by linking compound 1 covalently to compound 2. Such a molecule that is composed of two incompatible parts is called Self Incompatible Solvent in this work. In this thesis examples of incompatible compounds that show moderate incompatibility are chosen, therefore it was possible to do a comparison between simple physical mixtures and covalently linked incompatible molecules. The theoretical prediction of the theory is compared with experiments. This principle is calculated quantitatively for binary and ternary mixtures and compared with the experimental results in three distinct series of experiments: i) by using solution calorimetry and calculation of the interaction parameters between compounds 3 and the preexisting binary mixture of compound 1 and 2, ii) by using solution calorimetry and calculation of the interaction parameters between compound 3 and the Self Incompatible Solvent that correspond to the mixtures used in (i) and iii) from the saturation solubility of compound 3 in the Self Incompatible Solvent. The results obtained from the theoretical prediction and these obtained from the three different series of experiments show the same trend: the self incompatibility of the solvent improves the dissolution process.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / Sorption is a very effective methodology used to remove dyes from aqueous effluents. In this work, fish scales of Robalo (Dicentrarchus labrax) were used as a new adsorbent for the removal of a cationic dye (AZM) from aqueous solutions. The scales were characterized by TG/DTG, DSC, FTIR, XRD, SEM, RAMAN, solid-state reflectance spectrofotometry and zero-charge pH of the scales (pHpcz). The results have indicated that the Robalo scales are formed by type I collagen and hydroxyapatite, with pHpcz ~ 7,0. Kinetic studies were performed to evaluate the influence of contact time and temperature on the sorption behavior of the scale-AZM sorption processes. In general, the sorption of AZM on Robalo scales decreases as temperature increases. The kinetic data were best fitted to the Avrami exponential kinetic model, and the equilibrium sorption data to the Sips model. The values of the variations of enthalpy (ΔH), Gibbs free energies (ΔG) and entropy (ΔS) were calculated. It was observed that the scale-AZM processes are exothermic in nature, thermodynamically spontaneous with negative entropy variations. Solution calorimetry results have indicated that the sorption energies change in relation to the progressive occupation of the AZM sorption sites on Robalo scales. The results from both characterization and sorption studies have indicated that the interactions of scale-AZM have occurred mainly by the organic phase of the scales. The Robalo scales have shown excellent features to be used as a new and promising adsorbent for removal of cationic dyes from aqueous solutions. / Dentre os vários processos para a remoção de corantes de efluentes aquosos, o de sorção constitui um dos mais efetivos. O presente trabalho avaliou a utilização de escamas de peixe Robalo (Dicentrarchus labrax) como um novo material adsorvente para a remoção de do corante catiônico azul de metileno (AZM) de soluções aquosas. As escamas foram caracterizadas por TG/DTG, DSC, FTIR, DRX, MEV, RAMAN, espectrofotometria de absorção por reflectância no estado sólido e determinação do pH do ponto de carga zero (pHpcz). Os resultados indicaram que as escamas são constituídas por uma fase orgânica, o colágeno tipo I e por outra fase inorgânica, a hidroxiapatita, com pHpcz ~ 7,0. Estudos cinéticos foram realizados com o intuito de avaliar a influência do tempo de contato e da temperatura nos processos de sorção. Observou-se que o processo de sorção de AZM diminui com o aumento da temperatura. Foram aplicadas modelagens cinéticas que mostraram que o modelo cinético exponencial de Avrami ajusta-se melhor aos dados cinéticos. Estudos de sorção no equilíbrio indicaram melhores ajustes ao modelo de Sips. Determinaram-se os valores das variações de entalpia (ΔH), da energia livre de Gibbs (ΔG), e de entropia (ΔS) para os processos de sorção de AZM nas escamas. Observou-se que os processos de sorção são exotérmicos, espontâneos e ocorrem com diminuição de entropia. Medidas calorimétricas em solução indicaram que as energias dos sítios de sorção de AZM das escamas tornam-se mais negativas à medida que aumenta a capacidade de sorção de AZM nas escamas. Os resultados das caracterizações e dos estudos de sorção indicam que as interações escama-AZM ocorreram, predominantemente, utilizando-se a fase orgânica das escamas. Observou-se que as escamas de robalo apresentam excelentes perspectivas como um novo material adsorvente de baixo custo para a remoção de corantes catiônicos de soluções aquosas.

In dieser Arbeit wird das neue Prinzip der „Selbstinkompatiblen Lösungsmittel“ vorgestellt. Es wird theoretisch abgeleitet, dass eine Mischung aus zwei Substanzen mit ungünstigen Wechselwirkungen bereitwillig eine weitere Substanz aufnehmen sollte, die diese ungünstigen Wechselwirkungen durch Verdünnen vermindert. Dies sollte umso stärker ausgeprägt sein, je ungünstiger die Wechselwirkungen zwischen den beiden ersten Substanzen sind. Da sich jedoch Substanzen mit sehr ungünstigen Wechselwirkungen physikalisch nicht mischen, entstand die Idee, diese Substanzen durch eine kovalente Bindung aneinander zu binden. Ein solches Molekül, das aus zwei inkompatiblen Hälften besteht, wird im Folgendem Selbstinkompatibles Lösungsmittel genannt. Die in dieser Arbeit gewählten Substanzen zeigen mäßige Inkompatibilität, deshalb ist ein Vergleich zwischen einfachen physikalischen Mischungen und kovalent verknüpften Molekülhälften noch möglich. Dieses Prinzip wird für binäre und ternäre Mischungen quantitativ berechnet und experimentell in drei Serien von Experimenten bestätigt: i) unter Verwendung von Lösungskalorimetrie und Bestimmung der Wechselwirkungsparameter zwischen Komponente 3 und einer bereits hergestellt physikalischen binären Mischung aus Komponente 1 und 2, ii) unter Verwendung von Lösungskalorimetrie und Bestimmung der Wechselwirkungsparameter zwischen Komponente 3 und den selbstinkompatiblen Losungsmitteln, die den in (i) gewählten Mischungen entsprechen und iii) aus der Sättigungslöslichkeit der Komponente 3 in den entsprechenden selbstinkompatiblen Lösungsmitteln. In diesen drei verschiedenen Messserien wird stets der gleichen Trend beobachtet: Die Selbstinkompatibilität eines Lösungsmittels begünstigt den Lösevorgang. / In this thesis a new principle of Self Incompatible Solvent is introduced. It is shown theoretically that a preexisting mixture of two substances (compound 1 and 2) with unfavorable interactions will readily dissolve a third compound because it diminishes the unfavorable interaction between the compound 1 and 2 by dilution. This behavior should be the stronger the more unfavorable the interactions between compound 1 and 2 are. However, substances with strong unfavorable interactions will not mix. Therefore the idea pursued here is to enforce the desired preexisting mixture for example by linking compound 1 covalently to compound 2. Such a molecule that is composed of two incompatible parts is called Self Incompatible Solvent in this work. In this thesis examples of incompatible compounds that show moderate incompatibility are chosen, therefore it was possible to do a comparison between simple physical mixtures and covalently linked incompatible molecules. The theoretical prediction of the theory is compared with experiments. This principle is calculated quantitatively for binary and ternary mixtures and compared with the experimental results in three distinct series of experiments: i) by using solution calorimetry and calculation of the interaction parameters between compounds 3 and the preexisting binary mixture of compound 1 and 2, ii) by using solution calorimetry and calculation of the interaction parameters between compound 3 and the Self Incompatible Solvent that correspond to the mixtures used in (i) and iii) from the saturation solubility of compound 3 in the Self Incompatible Solvent. The results obtained from the theoretical prediction and these obtained from the three different series of experiments show the same trend: the self incompatibility of the solvent improves the dissolution process.