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| Author(s): |
Natalia Daniele Dorighello Carareto
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia de Alimentos |
| Defense date: | 2010-03-16 |
| Examining board members: |
Antonio José de Almeida Meirelles;
Maria Alvina Krähenbühl;
Rosiane Lopes da Cunha
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| Advisor: | Mariana Conceição da Costa; Antonio José de Almeida Meirelles |
| Abstract | |
Fatty alcohols are minor constituents of vegetal tissues, being mainly found in vegetal waxes. Fatty alcohols are used in industry as emulsifiers, surfactants or emollients agents. There are many studies about the use of fatty alcohol associated with fatty acids as substitutes for the hydrogenation process of margarine manufacturing and other edible emulsions, for example. Solid-liquid equilibrium of binary mixtures of fatty alcohols is na important tool for understanding the behavior of fatty complex mixtures. Thus, this work aimed to study diagrams of solid-liquid equilibrium of binary systems of even saturated fatty alcohols from eight to eighteen atoms in the carbon chain by differential scanning calorimetry (DSC). This method was previously used by Rolemberg (2002) and Costa et al. (2007a, 2009a, 2009b, 2009c) for fatty acids and triacylglycerols systems. To complement the study were also captured images for some systems by optical microscope with temperature control. The liquidus line of the studied systems showed three different behaviors: one showed only the eutectic point, another the eutectic and peritectic points or neither eutectic nor peritectic point. For systems that had peritectic point, it could be observed in the microscopy images the recrystallization of the compositions that was investigated on the microscopy, even with the temperature increase. This behavior corroborates the existence of the metatetic reaction in these systems. Margules-2-suffix, Margules-3-suffix, NRTL, UNIFAC and UNIFAC-Dortmund models were applied to fit the experimental data. The best fit for the systems that exhibit peritectic and eutectic points were obtained through Margules and NRTL models. UNIFAC and UNIFAC-Dortmund models have showed high deviation compared to experimental data of the modeled systems (AU) | |
| FAPESP's process: | 07/06162-1 - Solid-Liquid Phase Equilibrium of Fatty Alcohol Binary Mixtures by Differential Scanning Calorimetry |
| Grantee: | Natália Daniele Dorighello Carareto |
| Support Opportunities: | Scholarships in Brazil - Master |