No / The oligomerisation of L-amino acids by papain was studied in a mixer ball mill and in a planetary ball mill. The biocatalyst proved stable under the ball milling conditions providing the corresponding oligopeptides in good to excellent yields and with a variable degree of polymerisation. Both parameters were found to be dependent on the reaction conditions and on the nature of the amino acid (specifically on its side-chain size and hydrophobicity). In addition, the chemoenzymatic oligomerisation was demonstrated by utilising twin-screw extrusion technology, which allowed for a scalable continuous process. Finally, the synthesised oligo(L-Leu) 2b proved to be active as a catalyst in the Juliá–Colonna enantioselective epoxidation of chalcone derivatives. / We acknowledge RWTH Aachen University for support by the Distinguished Professorship Program funded by the Excellence Initiative of the German federal and state governments. We kindly acknowledge Marcus Frings and Plamena Staleva for the HPLC analysis of products 4a–c (RWTH Aachen University) and ASEP for the TGA analysis (Queen’s University Belfast). D. E. C. and S. L. J. acknowledge the agency EPSRC, grant no. EP/R019655/1. Part of this work was performed at the Center for Chemical Polymer Technology (CPT) unit of DWI, which was supported by the EU and the federal state of North Rhine-Westphalia (grant EFRE 30 00 883 02).

Developing a fundamental understanding of the interactions between catalytic surfaces and adsorbed molecules is imperative to the rational design of new materials for catalytic, sorption and gas separation applications. Experiments that probed the chemistry at the gas-surface interface were employed through the utilization of in situ infrared spectroscopic measurements in high vacuum conditions to allow for detailed and systematic investigations into adsorption and reactive processes. Specifically, the mechanistic details of propene epoxidation on the surface of nanoparticulate Au supported on TiO2 and dimethyl chlorophosphate (DMCP) decomposition on the surface of TiO2 aerogel-supported Cu nanoparticles were investigated. In situ infrared spectroscopy illustrates that TiO2-supported Au nanoparticles exhibit the unprecedented ability to produce the industrially relevant commodity chemical, propene oxide, through the unique adsorption configuration of propene on the surface of Au and a hydroperoxide intermediate (-OOH) in the presence of gaseous hydrogen and oxygen. Whereas, TiO2-supported Cu aerogels oxidize the organophosphate-based simulant, DMCP, into adsorbed CO at ambient environments. Through a variety of spectroscopic methods, each step in these oxidative pathways was investigated, including: adsorption, oxidation and reactivation of the supported-nanoparticle systems to develop full mechanistic pictures. Additionally, the perturbation of vibrational character of the probe molecule, CO, was employed to characterize the intrinsic µ3-hydroxyls and molecular-level defects associated with the metal-organic framework (MOF), UiO-66. The adsorption of CO onto heterogeneous surfaces effectively characterizes surfaces because the C-O bond vibrates differently depending on the nature of the surface site. Therefore, CO adsorption was used within the high vacuum environment to identify atomic-level characteristics that traditional methods of analysis cannot distinguish. / Doctor of Philosophy / The interaction between small gas molecules and solid surfaces is important for environmental, industrial and military applications. In order to chemically change molecules, surfaces act to lower activation barriers and provide a low energy plane to create new chemical bonds. To study the fundamental interactions that occur between gas molecules and surfaces, we employ infrared spectroscopy in order to probe the vibrations of bonds at the gas–surface interface. By tracking the chemical bonds that break and form on the surface of different materials, we can develop surface reaction pathways for a variety of different chemical reactions. We focus our efforts on two different applications: the conversion of propene to propene oxide for industrial applications and the decomposition of chemical warfare agents. Using the techniques described above, we were able to develop reaction pathways for both propene oxidation and chemical warfare agent simulant degradation. Our work is critical to the further development of catalysts that harness the specific structural and chemical properties we identify as important and exploit them for further use.

Im Rahmen der vorliegenden Arbeit wurde eine neuartige Methode und die entsprechenden Katalysatoren für die heterogen katalysierte Gasphasen-Epoxidation von Propen entwickelt und optimiert. Das Propen wurde an FeOx/SiO2-Katalysatoren mit N2O als Oxidationsmittel epoxidiert. Die Katalysatoren wurden mittels XRD, TEM, XPS, Physi- und Chemisorption, TPR/TPO, TPD und IR untersucht und charakterisiert. Der Einfluß der Reaktionsbedingungen auf die Oxidationsergebnisse wurde bestimmt und Untersuchungen zum Reaktionsablauf durchgeführt. Es wurden Selektivitäten zu Propenoxid von 40-70%, bei Propenumsätzen von 3-12%, erreicht. Die maximalen erzielten PO-Ausbeuten betrugen über 5%, und sind damit den berichteten Ergebnisse aus der Literatur überlegen.

This thesis describes the catalytic asymmetric epoxidation of olefins mediated by chiral iminum salts. The first chapter introduces some of the most novel and effective catalytic asymmetric methods for preparing chiral oxiranes. The second chapter is divided into three sections. The first section of chapter two is dedicated to our efforts to develop new aqueous oxidative conditions using both hydrogen peroxide and sodium hypochlorite as efficient, green oxidants that remove the temperature boundaries observed with the use of Oxone® as the stoichiometric oxidant. A wider range of available temperatures was examined allowing optimization of both oxidative systems. Ethereal hydrogen peroxide was observed to mediate asymmetric epoxidation within an acetonitrile monophasic co-solvent system giving enantioselectivities of up to 56%. When sodium hypochlorite was used in a biphasic solvent system in conjunction with dichloromethane; it was observed to mediate oxidation of the substrate alkenes in up to 71% ee. The second and third sections of chapter two are dedicated to our efforts to synthesize chiral iminium salts as catalysts for asymmetric epoxidation based on a biphenyl azepinium salt catalyst structure. From previous work within the Page group, the asymmetric synthesis and subsequent defined stereochemistry of a chiral carbon atom α to the iminium nitrogen atom was shown to have significant effect on the enantiocontrol of epoxidation using the iminium salt catalyst. Work was completed on biphenyl azepinium salt catalysts, inserting an alkyl or aryl Grignard reagent into the iminium bond using a pre-defined dioxane unit as a chiral auxiliary. Oxidation of the subsequent azepine gave a single diastereoisomerically pure azepinium salt. The methyl analogue of this sub-family of azepinium catalysts has been shown to give up to 81% ee for epoxidation of 1-phenylcyclohexene, furthermore, the binaphthalene azepinium salt with an additional methyl group was also synthesized and was shown to give up to 93% for epoxidation of 1-phenylcyclohexene. Continuation of the substitution α to the nitrogen atom gave rise to an interesting tetracyclic (biphenyl) azepinum salt catalyst. Construction of an asymmetric oxazolidine ring unit encapsulating the azepinium nitrogen and one of the methylene carbon atoms was achieved. In doing so two chiral centres α to the nitrogen atom were generated. The azepinium chiral carbon atom was populated by an addition methyl group with variation in the substitution on the oxazolidine chiral carbon atom. The benzyl analogue of this sub-family of tetracyclic azepinium catalysts has shown to give up to 79% ee for epoxidation 1-phenylcyclohexene. The third chapter is the experimental section and is dedicated to the methods of synthesis and characterization of the compounds mentioned in the previous chapter. X-ray reports regarding the crystallographic analysis of the structures presented in chapter two are provided in appendix A. Appendix B contains the analytical spectra for the determination of enantiomeric excess of the epoxides.

Óleo de soja epoxidado (OSE) é um produto químico há muito tempo utilizado como co-estabilizante e plastificante secundário do poli (cloreto de vinila) (PVC), ou seja, como um material que tem limitações na quantidade máxima que pode ser usada no composto de PVC. A sua aplicação como plastificante primário, ou seja, como o principal elemento plastificante no composto de PVC, e como base para outros plastificantes de fontes renováveis, tem aumentado nos últimos anos, principalmente devido a melhorias de desempenho e à redução do custo do OSE em comparação com plastificantes tradicionais. A reação de epoxidação do óleo de soja é bem conhecida e ocorre em duas fases líquidas, com reações em ambas as fases, e transferência de massa entre as fases. O processo industrial mais utilizado conta com formação in-situ do ácido perfórmico, através da adição gradativa do principal reagente, o peróxido de hidrogênio a uma mistura agitada de ácido fórmico e óleo de soja refinado. Industrialmente, o processo é realizado em batelada, controlando a adição do reagente peróxido de hidrogênio de forma que a geração de calor não ultrapasse a capacidade de resfriamento do sistema. O processo tem um ciclo que pode variar entre 8 e 12 horas para atingir a conversão desejada, fazendo com que a capacidade de produção seja dependente de investimentos relativamente pesados em reatores agitados mecanicamente, que apresentam diversos riscos de segurança. Estudos anteriores não exploram em profundidade algumas potenciais áreas de otimização e redução das limitações dos processos, como a intensificação da transferência de calor, que permite a redução do tempo total de reação. Este trabalho avalia experimentalmente e propõe uma modelagem para a reação de epoxidação do óleo de soja em condições de remoção de calor máxima, o que permite que os reagentes sejam adicionados em sua totalidade no início da reação, simplificando o processo. Um modelo foi ajustado aos dados experimentais. O coeficiente de troca térmica, cuja estimativa teórica pode incorrer em erros significativos, foi calculado a partir de dados empíricos e incluído na modelagem, acrescentando um fator de variabilidade importante em relação aos modelos anteriores. O estudo propõe uma base teórica para potenciais alternativas aos processos adotados atualmente, buscando entender as condições necessárias e viáveis em escala industrial para redução do ciclo da reação, podendo inclusive apoiar potenciais estudos de implementação de um reator contínuo, mais eficiente e seguro, para esse processo. / Epoxidized soybean oil (ESBO) has been largely used commercially, especially in the poly (vinyl chloride) (PVC) industry. For that market, until recently, ESBO was applied only as a co-stabilizer and a secondary plasticizer, where the material is considered partially compatible and presents limitations to the allowed concentration in PVC compounds. The application of this material as a primary plasticizer, where ESBO is the main plasticizer of the formulation, and also as building block for other bio-based primary plasticizers has been growing significantly in the past years, mainly due to better quality of the epoxidized products and reduced cost over traditional petroleum based materials. The epoxidation of vegetable oils is a well know process that occurs in two liquid phases, with reactions in both phases and mass transfer between phases. The most commonly used industrial process employs mechanically agitated lengthy batch reactions, with gradual addition of hydrogen peroxide, in order to keep heat generation below maximum heat removal capacity. This process has a cycle that may vary between 8 to 12 hours to reach the desired conversion, and depends on relatively high investments, in addition to several safety concerns. Previous studies have not explored in detail a potential optimization of the processes by heat transfer intensification, in order to maximize conversion, reduce reaction times, and improve safety. The present research offers a better understanding of the kinetic and transport phenomena variables of the epoxidation reaction under maximum heat removal conditions, which allow complete addition of all reagents at once. The present study evaluates experimentally and proposes a reaction simulation model under these conditions. The thermal exchange coefficient, for which theoretical estimates may incur in significant errors, was calculated from empirical results and included in the model, adding an important variability factor when compared to previous models. The study also proposes the initial bases to understand the necessary conditions to reduce the reaction cycle and allow the evaluation of a continuous, more efficient and safer reaction system.

This thesis sought to expand upon the synthetic application of the underexploited ipso, ortho diene cis-diol microbial arene oxidation product from benzoic acid. The microbial oxidation of benzoic acid by mutant strains of bacteria to give the ipso, otho diene cis-diol may be considered to be a green and clean method. This biocatalytic route yields large quantities of an enantiopure chiral building block, which is not assessable via traditional synthetic methods. The fermentation product has seen application towards the synthesis of aminocylitols, which have been tested for their biological activity. Attempts to synthesise the fully oxygenated counterparts, cyclitols, were investigated. Expansion of previous work using a bromine substituted derivative led to a range of cross-coupled and iron co-ordinated products. Finally, a range of novel chiral acids and ketones were synthesised and evaluated for their catalytic activity towards asymmetric epoxidation.

<p>Cilj ove doktorske disertacije je postavljanje<br />matematičkog modela složenog trofaznog reakcionog<br />sistem za epoksidovanje sojinog ulja in situ formiranom<br />persirćetnom kiselinom iz sirćetne kiseline i vodonik<br />peroksida u prisustvu jonoizmenjivačke smole kao<br />katalizatora. Model uzima u obzir koncentracije<br />reaktanata i produkata u vodenoj i uljnoj fazi. Pored<br />osnovnih reakcija stvaranja persirćetne kiseline i<br />epoksida, model obuhvata i sporednu reakciju otvaranja<br />epoksi prstena sa sirćetnom kiselinom. Za modelovanje<br />reakcije formiranja persirćetne kiseline na povr&scaron;ini<br />katalizatora primenjeni su Langmuir-Hinshelwood-<br />Hougen-Watson i Rideal-Eley postulati. Postavljeni<br />trofazni model predstavlja sistem običnih diferencijalnih<br />jednačina prvog reda koji opisuje promenu broja molova<br />komponenata i funkcionalnih grupa sa vremenom<br />izvođenja procesa epoksidovanja, i sadrži vi&scaron;e parametara<br />razvrstanih na kinetičke, termodinamičke i parametre koji<br />se odnose na prenos mase. Parametri modela zavise od<br />uslova izvođenja epoksidovanja i to svi od temperature, a<br />neki i od sastava i inteziteta me&scaron;anja.<br />Za konstantu hemijske ravnoteže reakcije nastajanja<br />persirćetne kiseline je izvedena semiteorijska zavisnost<br />od temperature koja daje vrednosti istog reda veličine i<br />istog smera promene sa temperaturom kao i većina<br />podataka objavljenih u literaturi.<br />Za izračunavanje koeficijenta raspodele sirćetne kiseline<br />između uljne i vodene faze potrebno je odrediti zavisnost<br />konstante fazne ravnoteže tečno-tečno sirćetne kiseline od<br />sastava i temperature. Utvrđeno je da je UNIFAC model<br />grupnih doprinosa za koeficijente aktivnosti nepogodan<br />za predskazivanje ravnoteže tečno-tečno. Eksperimentalni<br />podaci za ovu konstantu ravnoteže su uspe&scaron;no korelisani<br />UNIQUAC modelom za koeficijente aktivnosti.<br />Parametri reparametrizovane Arrheniusove zavisnosti<br />konstanti brzina reakcija i konstanti sorpcije učesnika<br />reakcije stvaranja persirćetne kiseline od temperature<br />određeni su simultano sa parametrima koji se odnose na<br />prenos mase i sa odnosom koeficijenata raspodele<br />persirćetne i sirćetne kiseline između uljne i vodene faze,<br />fitovanjem eksperimentalnih podataka epoksidovanja<br />sojinog ulja, tj. minimizacijom sume kvadrata odstupanja<br />računskih od eksperimentalno određenih vrednosti jodnog<br />broja i sadržaja epoksi kiseonika tokom epoksidovanja.<br />Fitovanje je uspe&scaron;no izvedeno primenom metode<br />Marquardta, dok su pomenute računske vrednosti<br />dobijene numeričkom integracijom sistema<br />diferencijalnih jednačina modela primenom Runge-Kutta<br />metode IV reda.</p> / <p>The objective of this doctoral thesis was development of<br />mathematical model for complex three-phase reaction<br />system for soybean oil epoxidation with peracetic acid<br />formed in situ from acetic acid and hydrogen peroxide in a<br />presence of an ion exchange resin as catalyst. The local<br />concentrations of components in water and oil phases were<br />introduced into the model. In addition to reactions of the<br />peracetic acid and epoxy compound formation, model<br />considers the side reaction of epoxy ring cleavage with<br />acetic acid. Approximate modeling of peracetic acid<br />formation was based on Langmuir-Hinshelwood-Hougen-<br />Watson and Rideal-Eley postulates. Established threephase<br />model is a system of ordinary first order differential<br />equations which describes change of components and<br />functional groups amounts with reaction time. Besides<br />kinetic parameters, model comprises the thermodynamic<br />ones as well as parameters of mass transfer between the oil<br />and water phase. All model parameters are dependent on<br />temperature and some additionally on composition and<br />intensity of stirring.<br />A semitheoretical temperature dependency of chemical<br />equilibrium constant for peracetic acid formation was<br />established. The order of magnitude and temperature trend<br />of the calculated chemical equilibrium constant are in<br />agreement with the most data given in a literature.<br />For calculation of partition coefficient for acetic acid<br />between oil and water phase, temperature and composition<br />dependency of liquid-liquid equilibrium constant for acetic<br />acid is necessary. It was found that UNIFAC model of<br />group contribution was non-applicable for the prediction<br />of the equilibrium constant. The experimental data for the<br />equilibrium constant were, however, successfully fitted by<br />UNIQUAC model.<br />Temperature dependencies of the reaction rate constants<br />and sorption constants of reactants and products in<br />peracetic acid formation reaction are expressed by<br />reparameterized Arrhenius equation. The parameters of<br />such equation were determined simultaneously with mass<br />transfer parameters and ratio of peracetic acid and acetic<br />acid partition coefficients between oil and water phase by<br />fitting the experimental data i.e. by minimization of least<br />sum of squares of deviation between the calculated and<br />experimentally determined iodine value and epoxy oxygen<br />content . Marquardt method was successfully used to fit<br />the experimental data. A fourth-ordered Runge-Kutta<br />method was applied for integrating the system of<br />differential equations of the model.</p>

The reactions which give the products ethylene oxide, vinyl alcohol, vinyl aldehyde and vinyl radical for ethylene oxidation and the reactions which give propylene oxide, propanal, acetone and pi-allyl radical for propylene oxidation were investigated by using Density Functional Theory (DFT) method with B3LYP/LanL2DZ and 6-31g(d,p) basis sets in Gaussian&rsquo / 03 software. Silver and silver oxide were used as catalyst surface cluster models. Surface comparison was made for silver (111), (110) and (100) surfaces. Ethylene oxidation reaction was studied on these silver surfaces. Oxygen effect on ethylene oxide formation reaction was also investigated on silver (111) surface. Ethylene and propylene oxidation reactions were completed on both Ag13(111) and Ag14O9(001) surface clusters. VASP software which utilizes periodic plane wave basis sets was also used to compare trends of reactions for ethylene and propylene oxidations obtained by using Gaussian&rsquo / 03 software. According to results, silver (110) surface is more active for ethylene oxide formation than (111) and (100) surfaces. Hill site of (110) surface is much more active than hollow site of (110) surface since oxygen atom weakly adsorbed on hill site. Ethyl aldehyde and vinyl alcohol can not be formed on Ag(111) surface because of those higher activation barriers while ethylene oxide can be formed on cluster. Activation barrier for ethylene oxide formation decreases with increasing oxygen coverage on Ag(111) surface. Ethylene oxametallocycle intermediate molecule was not formed on Ag2O(001) surface while it is formed on surface oxide structure on Ag(111). Ethyl aldehyde and vinyl alcohol are not formed on silver oxide (001) surface. For propylene oxidation, &amp / #928 / -allyl formation path has the lowest activation barrier explaining why silver is not a good catalyst for the propylene oxide formation while it is a good catalyst for the ethylene oxide formation. This situation is valid for silver oxide. Propylene oxide selectivity increased in the gas phase oxidation. The qualitative relative energy trend obtained by VASP software is the similar with that of calculations obtained by using GAUSSIAN&rsquo / 03 software.

Orientador: Prof. Dr. Dalmo Mandelli / Tese (doutorado) - Universidade Federal do ABC. Programa de Pós-Graduação em Ciência e Tecnologia/Química, 2017. / A oxidacao de compostos organicos tem sido muito estudada nas ultimas decadas e e uma das areas de estudo mais atrativas da quimica moderna. Este tipo de reacao leva a obtencao de produtos de grande aplicacao na industria farmaceutica, de plasticos e fragrancias, como alcoois, cetonas e epoxidos. Varios trabalhos tem sido realizados no sentido de se desenvolver novos catalisadores ativos e seletivos, que tambem possuam custo e toxicidade relativamente baixos, com a finalidade de se obter processos que levem a quantidade cada vez menor de subprodutos e residuos de reacao, dentro do contexto da quimica-verde. Este trabalho foi dividido em duas partes, consistindo a primeira de um Planejamento de Experimentos Fracionario (27-4), nos quais foi possivel definir as principais variaveis que afetam a atividade catalitica dos oxidos de aluminio e galio, a saber: pH final, velocidade de resfriamento e solvente. Na segunda parte, estas variaveis foram exploradas em um Planejamento de Experimentos Completo 23. Por meio das analises de Fisissorcao de N2 e Dessorcao Termoprogramada de Amonia, foi possivel correlacionar algumas das propriedades fisico-quimicas dos catalisadores sintetizados com sua atividade catalitica. Com relacao a acidez dos catalisadores, pH e solvente apresentaram-se como as variaveis mais significativas: houve, em media, reducao da acidez em 1,0 mmolNH3 g-1 ao se realizar a sintese em pH 10 ao inves de pH 9 para Al2O3 e 1,1 mmolNH3 g-1 para Ga2O3; a troca de solvente de etilenoglicol por glicerol causou reducao de 0,60 mmolNH3 g-1 para Al2O3, enquanto houve um aumento de 1,2 mmolNH3 g-1 para Ga2O3. Para as propriedades fisicas, o solvente foi a variavel mais importante; os valores de area superficial, variaram entre 265 e 479 m2 g-1 para Al2O3, havendo um aumento medio de 136 m2 g-1 ao se utilizar glicerol, enquanto que os valores obtidos para Ga2O3 ficaram entre 81 e 280 m2 g-1, com efeito de positivo de 95 m2 g-1 ao se substituir etilenoglicol por glicerol. Com relacao as propriedades cataliticas, verificou-se que o uso de glicerol como solvente resultou em aumento medio de 10,1 % nos rendimentos para Al2O3 durante a epoxidacao de cicloocteno; os melhores resultados foram obtidos com rendimento de 53 % apos 6 h de reacao. Por outro lado, todos os oxidos de galio apresentaram rendimentos superiores a 98 % apos 4 h. A adicao dos acidos HNO3 e TFA como co-catalisadores da reacao de epoxidacao de cicloocteno com Al2O3 e Acido Acetico como co-catalisador do Ga2O3 causaram aumento substancial na velocidade inicial, mais que dobrando seu valor ao se utilizar os mesmos; por outro lado, a adicao de bases, como PCA, levaram a reducoes na atividade catalitica dos sistemas. Outros alquenos, como decen-1-eno, e terpenos, incluindo limoneno, ¿¿-pineno, linalol, geraniol e citral foram testados, resultando em rendimentos que variaram entre 19 e 51 % para A2O3 (10 h) e entre 31 e 100 % para Ga2O3 (7 h). / The oxidation of organic compounds has been much studied in recent decades and is one of the most attractive areas of study in modern chemistry. This type of reaction leads to the obtaining of products of great application in the pharmaceutical, plastics and fragrances industry, like alcohols, ketones and epoxides. Several works have been carried out in order to develop new active and selective catalysts, which also have relatively low cost and toxicity, in order to obtain processes that lead to the decreasing amount of by-products and reaction residues within the context of green chemistry. This work was divided in two parts, consisting the first of a Fractional Factorial Designs (27-4), in which it was possible to define the main variables that affect the catalytic activity of aluminum and gallium oxides, namely: final pH, cooling rate and solvent. In the second part, these variables were explored in a Complete Factorial Designs 23. Through the analysis of N2 Fisissorption and Thermoprogrammed Ammonia Desorption, it was possible to correlate some of the physicochemical properties of the catalysts synthesized with their catalytic activity. In relation to the acidity of the catalysts, pH and solvent were the most significant variables: there was, on average, acidity reduction of 1.0 mmolNH3 g-1 when the synthesis was performed at pH 10 instead of pH 9 for Al2O3 and 1.1 mmolNH3 g-1 for Ga2O3; The exchange of ethylene glycol solvent for glycerol caused a reduction of 0.60 mmolNH3 g-1 to Al2O3, while there was an increase of 1.2 mmolNH3 g-1 for Ga2O3. For the physical properties, the solvent was the most important variable; the values of surface area ranged from 265 to 479 m² g-1 for Al2O3, with an average increase of 136 m² g-1 when using glycerol, while Ga2O3 values were between 81 and 280 m² g-1, with positive effect of 95 m² g-1 when ethylene glycol was substituted by glycerol. Regarding the catalytic properties, it was found that the use of glycerol as solvent resulted in an average increase of 10,1 % in the yields for Al2O3 during cyclooctene epoxidation; the best results were obtained with 53% yield after 6 h of reaction. On the other hand, all gallium oxides presented yields higher than 98% after 4 h. The addition of the HNO3 and TFA acids as co-catalysts of the cyclooctene epoxidation reaction with Al2O3 and acetic acid as co-catalyst of Ga2O3 caused a substantial increase in the initial velocity, rather than doubling their values; on the other hand, the addition of bases, such as PCA, led to reductions in the catalytic activity of the systems. Other alkenes, such as dec-1-ene, and terpenes, including limonene, á-pinene, linalool, geraniol and citral were tested, giving yields ranging from 19 to 51 % for A2O3 (10 h) and between 31 and 100 % for Ga2O3 (7 h).

Óleo de soja epoxidado (OSE) é um produto químico há muito tempo utilizado como co-estabilizante e plastificante secundário do poli (cloreto de vinila) (PVC), ou seja, como um material que tem limitações na quantidade máxima que pode ser usada no composto de PVC. A sua aplicação como plastificante primário, ou seja, como o principal elemento plastificante no composto de PVC, e como base para outros plastificantes de fontes renováveis, tem aumentado nos últimos anos, principalmente devido a melhorias de desempenho e à redução do custo do OSE em comparação com plastificantes tradicionais. A reação de epoxidação do óleo de soja é bem conhecida e ocorre em duas fases líquidas, com reações em ambas as fases, e transferência de massa entre as fases. O processo industrial mais utilizado conta com formação in-situ do ácido perfórmico, através da adição gradativa do principal reagente, o peróxido de hidrogênio a uma mistura agitada de ácido fórmico e óleo de soja refinado. Industrialmente, o processo é realizado em batelada, controlando a adição do reagente peróxido de hidrogênio de forma que a geração de calor não ultrapasse a capacidade de resfriamento do sistema. O processo tem um ciclo que pode variar entre 8 e 12 horas para atingir a conversão desejada, fazendo com que a capacidade de produção seja dependente de investimentos relativamente pesados em reatores agitados mecanicamente, que apresentam diversos riscos de segurança. Estudos anteriores não exploram em profundidade algumas potenciais áreas de otimização e redução das limitações dos processos, como a intensificação da transferência de calor, que permite a redução do tempo total de reação. Este trabalho avalia experimentalmente e propõe uma modelagem para a reação de epoxidação do óleo de soja em condições de remoção de calor máxima, o que permite que os reagentes sejam adicionados em sua totalidade no início da reação, simplificando o processo. Um modelo foi ajustado aos dados experimentais. O coeficiente de troca térmica, cuja estimativa teórica pode incorrer em erros significativos, foi calculado a partir de dados empíricos e incluído na modelagem, acrescentando um fator de variabilidade importante em relação aos modelos anteriores. O estudo propõe uma base teórica para potenciais alternativas aos processos adotados atualmente, buscando entender as condições necessárias e viáveis em escala industrial para redução do ciclo da reação, podendo inclusive apoiar potenciais estudos de implementação de um reator contínuo, mais eficiente e seguro, para esse processo. / Epoxidized soybean oil (ESBO) has been largely used commercially, especially in the poly (vinyl chloride) (PVC) industry. For that market, until recently, ESBO was applied only as a co-stabilizer and a secondary plasticizer, where the material is considered partially compatible and presents limitations to the allowed concentration in PVC compounds. The application of this material as a primary plasticizer, where ESBO is the main plasticizer of the formulation, and also as building block for other bio-based primary plasticizers has been growing significantly in the past years, mainly due to better quality of the epoxidized products and reduced cost over traditional petroleum based materials. The epoxidation of vegetable oils is a well know process that occurs in two liquid phases, with reactions in both phases and mass transfer between phases. The most commonly used industrial process employs mechanically agitated lengthy batch reactions, with gradual addition of hydrogen peroxide, in order to keep heat generation below maximum heat removal capacity. This process has a cycle that may vary between 8 to 12 hours to reach the desired conversion, and depends on relatively high investments, in addition to several safety concerns. Previous studies have not explored in detail a potential optimization of the processes by heat transfer intensification, in order to maximize conversion, reduce reaction times, and improve safety. The present research offers a better understanding of the kinetic and transport phenomena variables of the epoxidation reaction under maximum heat removal conditions, which allow complete addition of all reagents at once. The present study evaluates experimentally and proposes a reaction simulation model under these conditions. The thermal exchange coefficient, for which theoretical estimates may incur in significant errors, was calculated from empirical results and included in the model, adding an important variability factor when compared to previous models. The study also proposes the initial bases to understand the necessary conditions to reduce the reaction cycle and allow the evaluation of a continuous, more efficient and safer reaction system.