Made available in DSpace on 2015-04-14T13:58:46Z (GMT). No. of bitstreams: 1 437800.pdf: 2143579 bytes, checksum: 27291e3f6641f7a5b986a21239266159 (MD5) Previous issue date: 2012-03-30 / The decaffeination of leaves of yerba mate is economically attractive, since it allows to obtain products of commercial interest and caffeine, a byproduct used in food and pharmaceutical industries. In this work we used the extraction and precipitation with supercritical carbon dioxide to obtain the decaffeinated yerba mate and micro/nanoparticles of the caffeine. The decaffeinated yerba mate and extract were obtained from the dry leaves on automated pilot plant. The mathematical modeling was realized with the extraction curves defining the condition of the pressure and temperature for higher yield and lower caffeine content in yerba mate. For the micronization process based on the use of supercritical carbon dioxide as antisolvent (SAS process, Supercritical AntiSolvent) it was used a semi-continuous pilot plant. The influence of the initial concentration, the temperature and the pressure in the yield, in the particle size, in the morphology and polymorphism were analyzed. The results demonstrated that carbon dioxide is selective for caffeine and the condition which obtains higher yields of extract and less content of the caffeine in the extracted yerba mate was 15.0 MPa and 323,15 K . The average reduction of caffeine in yerba mate was 40%. The particles were micronized from caffeine solution with dichloromethaneand the analysis of the product showed a narrower range of sizes (2.5 to 6.5 μm) in comparison to unprocessed caffeine (12.2 μm) with an increment of the purity of caffeine. We also found that with proper selection of process parameters such as temperature, pressure and initial concentration, it is possible to produce particles of caffeine with different degrees of crystallinity and distinct quantities of polimorphics. / A descafeiniza??o de folhas de erva-mate ? economicamente atrativa, pois possibilita a obten??o de produtos descafeinados de interesse comercial e cafe?na, um bioproduto utilizado na ind?stria aliment?cia e farmac?utica. Neste trabalho utilizaram-se a extra??o e a precipita??o supercr?tica com di?xido de carbono para obten??o da erva mate descafeinada e de micro/nanopart?culas de cafe?na. A ervamate descafeinada e o extrato foram obtidos a partir da erva-mate seca em uma planta piloto automatizada. Com as curvas de extra??o procedeu-se a modelagem matem?tica definindo qual a condi??o de press?o e temperatura de extra??o para maior rendimento e menor teor de cafe?na na erva-mate. O processo de microniza??o baseou-se no uso do di?xido de carbono supercr?tico como antisolvente (processo SAS Supercritical Antisolvent) em uma planta piloto semicont?nua. A influ?ncia da concentra??o inicial, temperatura e press?o no rendimento, tamanho de part?cula, morfologia e polimorfismo foram analisados. Os resultados demonstraram que o di?xido de carbono ? seletivo para a cafe?na e que a condi??o em que se obt?m o maior rendimento de extrato e menor quantidade em massa de cafe?na na erva-mate extra?da ? a de 15,0 MPa e 323,15 K. A redu??o m?dia da cafe?na na erva-mate foi de 40%. As part?culas de cafe?na foram micronizadas a partir de solu??es com diclorometano. A an?lise do produto apresentou uma faixa mais estreita de tamanhos (2,5 a 6,5 μm) em compara??o com a cafe?na n?o processada (12,2 μm), com aumento de pureza da cafe?na. Foi encontrado tamb?m que com adequada sele??o dos par?metros do processo como temperatura, press?o e concentra??o inicial, ? poss?vel produzir part?culas de cafe?na com distintos graus de cristalinidade e diferentes quantidades dos polim?rficos.

Made available in DSpace on 2015-04-14T13:59:14Z (GMT). No. of bitstreams: 1 466218.pdf: 1839839 bytes, checksum: b88b0a1aef8f28f8586a8a5527e57608 (MD5) Previous issue date: 2015-03-03 / The interest in micro and nanoparticles has grown recently, since the technological advancement increased the possibilities for production and manipulation of these particles. The applications in different sectors, such as pigments, explosives, polymers, pharmaceuticals and superconductors, nanotechnology has increasingly attracted the interest of governments, academic researchers and industry. Among the technologies for obtaining micro- and nanoparticles, stand out those which make use of supercritical antisolvent (SAS). This method enables the obtainment of smaller particles with a more homogeneous size distribution than traditional ones, often eliminating the presence of residual solvent in the particles. In this context, this work aims to build, implant and perform validation test of a SAS process pilot unit, seeking the incorporation of this equipment as a technological tool for development and innovation associated with the production of nanoparticles. The implementation of this project started with the propose of SAS process flowchart; followed by sizing and acquisition of vessels, piping, valves and other necessary items for the equipment assembly, based on the supercritical extraction pilot plant installed at LOPE / PUCRS. In order to validate the equipment, caffeine particles were produced under different experimental conditions. The best performance of the precipitation process was achieved at 100 bar and 60 ? C. The caffeine particles obtained using the deployed equipment were analyzed for morphology and size using images taken by a scanning electron microscope (SEM) and the results were similar to those found in the literature. / O interesse em micro e nanopart?culas tem crescido nos ?ltimos anos, uma vez que o avan?o tecnol?gico ampliou as possibilidades de produ??o e manipula??o dessas part?culas. Por ter aplica??es em diferentes setores, tais como os de pigmentos, explosivos, pol?meros, f?rmacos e supercondutores, a nanotecnologia tem atra?do cada vez mais o interesse de governos, pesquisadores acad?micos e ind?strias. Dentre as tecnologias para obten??o de micro e nanopart?culas, destacam-se as que fazem uso de antissolvente supercr?tico (SAS), visto que possibilitam a obten??o de part?culas menores e com distribui??o granulom?trica mais homog?nea do que os m?todos tradicionais, al?m de muitas vezes eliminarem a presen?a de solvente residual nas part?culas obtidas. Neste contexto, este trabalho tem por objetivo construir, implantar e realizar testes de valida??o de uma unidade piloto experimental do processo SAS, visando incorpora??o deste equipamento como instrumento de desenvolvimento tecnol?gico e inova??o associado ? produ??o de nanopart?culas. A execu??o do projeto iniciou com a proposi??o do fluxograma de processo SAS; em seguida foram dimensionados e adquiridos vasos, tubula??es, conex?es, v?lvulas e outros acess?rios necess?rios para a montagem do equipamento, tendo como base a unidade piloto de extra??o supercr?tica instalada no LOPE/PUCRS. Para valida??o do equipamento, part?culas de cafe?na foram produzidas em diferentes condi??es experimentais. A condi??o mais favor?vel para o melhor rendimento no processo de precipita??o foi a de 100 bar e 60 oC. A produ??o de part?culas de cafe?na no equipamento implementado reproduziu os resultados encontrados na literatura quanto ? morfologia e dimens?o das part?culas obtidas, analisadas atrav?s de imagens obtidas por um microsc?pio eletr?nico de varredura (MEV).