Degradação fotocatalítica oxidativa do fenol utilizando carvão obtido da pirólise de diferentes biomassas

The modern industrial progress has been contaminating water with phenolic compounds. These are toxic and carcinogenic substances and it is essential to reduce its concentration in water to a tolerable one, determined by CONAMA, in order to protect the living organisms. In this context, this work focuses on the treatment and characterization of catalysts derived from the bio-coal, by-product of biomass pyrolysis (avelós and wood dust) as well as its evaluation in the phenol photocatalytic degradation reaction. Assays were carried out in a slurry bed reactor, which enables instantaneous measurements of temperature, pH and dissolved oxygen. The experiments were performed in the following operating conditions: temperature of 50 °C, oxygen flow equals to 410 mL min-1 , volume of reagent solution equals to 3.2 L, 400 W UV lamp, at 1 atm pressure, with a 2 hours run. The parameters evaluated were the pH (3.0, 6.9 and 10.7), initial concentration of commercial phenol (250, 500 and 1000 ppm), catalyst concentration (0, 1, 2, and 3 g L-1 ), nature of the catalyst (activated avelós carbon washed with dichloromethane, CAADCM, and CMADCM, activated dust wood carbon washed with dichloromethane). The results of XRF, XRD and BET confirmed the presence of iron and potassium in satisfactory amounts to the CAADCM catalyst and on a reduced amount to CMADCM catalyst, and also the surface area increase of the materials after a chemical and physical activation. The phenol degradation curves indicate that pH has a significant effect on the phenol conversion, showing better results for lowers pH. The optimum concentration of catalyst is observed equals to 1 g L-1 , and the increase of the initial phenol concentration exerts a negative influence in the reaction execution. It was also observed positive effect of the presence of iron and potassium in the catalyst structure: betters conversions were observed for tests conducted with the catalyst CAADCM compared to CMADCM catalyst under the same conditions. The higher conversion was achieved for the test carried out at acid pH (3.0) with an initial concentration of phenol at 250 ppm catalyst in the presence of CAADCM at 1 g L-1 . The liquid samples taken every 15 minutes were analyzed by liquid chromatography identifying and quantifying hydroquinone, p-benzoquinone, catechol and maleic acid. Finally, a reaction mechanism is proposed, cogitating the phenol is transformed into the homogeneous phase and the others react on the catalyst surface. Applying the model of Langmuir-Hinshelwood along with a mass balance it was obtained a system of differential equations that were solved using the Runge-Kutta 4th order method associated with a optimization routine called SWARM (particle swarm) aiming to minimize the least square objective function for obtaining the kinetic and adsorption parameters. Related to the kinetic rate constant, it was obtained a magnitude of 10-3 for the phenol degradation, 10-4 to 10-2 for forming the acids, 10-6 to 10-9 for the mineralization of quinones (hydroquinone, p-benzoquinone and catechol), 10-3 to 10-2 for the mineralization of acids.

Avaliação do tratamento eletroquímico (direto e indireto) como alternativa de degradação do corante azul de metileno

Textile industry has been a cause of environmental pollution, mainly due to the generation of large volumes of waste containing high organic loading and intense color. In this context, this study evaluated the electrochemical degradation of synthetic effluents from textile industry containing Methylene Blue (AM) dye, using Ti/IrO2-Ta2O5 and Ti/Pt anodes, by direct and indirect (active chlorine) electrooxidation. We evaluated the influence of applied current density (20, 40 and 60 mA/cm2 ), and the presence of different concentrations of electrolyte (NaCl and Na2SO4), as well as the neutral and alkaline pH media. The electrochemical treatment was conducted in a continuous flow reactor, in which the electrolysis time of the AM 100 ppm was 6 hours. The performance of electrochemical process was evaluated by UV-vis spectrophotometry, chemical oxygen demand (COD) and total organic carbon (TOC). The results showed that with increasing current density, it was possible to obtain 100 % of color removal at Ti/IrO2-Ta2O5 and Ti/Pt electrodes. Regarding the color removal efficiency, increasing the concentration of electrolyte promotes a higher percentage of removal using 0,02 M Na2SO4 and 0,017 M NaCl. Concerning to the aqueous medium, the best color removal results were obtained in alkaline medium using Ti/Pt. In terms of organic matter, 86 % was achieved in neutral pH medium for Ti/Pt; while a 30 % in an alkaline medium. To understand the electrochemical behavior due to the oxygen evolution reaction, polarization curves were registered, determining that the presence of NaCl in the solution favored the production of active chlorine species. The best results in energy consumption and cost were obtained by applying lower current density (20 mA/cm2 ) in 6 hours of electrolysis.

Avaliação do desempenho da paligorsquita modificada e do carvão da pirólise do lodo de esgoto no processo de degradação fotocatalítica do fenol

The uncontrolled disposal of wastewaters containing phenolic compounds by the industry has caused irreversible damage to the environment. Because of this, it is now mandatory to develop new methods to treat these effluents before they are disposed of. One of the most promising and low cost approaches is the degradation of phenolic compounds via photocatalysis. This work, in particular, has as the main goal, the customization of a bench scale photoreactor and the preparation of catalysts via utilization of char originated from the fast pyrolysis of sewage sludge. The experiments were carried out at constant temperature (50°C) under oxygen (410, 515, 650 and 750 ml min-1). The reaction took place in the liquid phase (3.4 liters), where the catalyst concentration was 1g L-1 and the initial concentration of phenol was 500 mg L-1 and the reaction time was set to 3 hours. A 400 W lamp was adapted to the reactor. The flow of oxygen was optimized to 650 ml min-1. The pH of the liquid and the nature of the catalyst (acidified and calcined palygorskite, palygorskite impregnated with 3.8% Fe and the pyrolysis char) were investigated. The catalytic materials were characterized by XRD, XRF, and BET. In the process of photocatalytic degradation of phenol, the results showed that the pH has a significant influence on the phenol conversion, with best results for pH equal to 5.5. The phenol conversion ranged from 51.78% for the char sewage sludge to 58.02% (for palygorskite acidified calcined). Liquid samples analyzed by liquid chromatography and the following compounds were identified: hydroquinone, catechol and maleic acid. A mechanism of the reaction was proposed, whereas the phenol is transformed into the homogeneous phase and the others react on the catalyst surface. For the latter, the Langmuir-Hinshelwood model was applied, whose mass balances led to a system of differential equations and these were solved using numerical methods in order to get estimates for the kinetic and adsorption parameters. The model was adjusted satisfactorily to the experimental results. From the proposed mechanism and the operating conditions used in this study, the most favored step, regardless of the catalyst, was the acid group (originated from quinone compounds), being transformed into CO2 and water, whose rate constant k4 presented value of 0.578 mol L-1 min-1 for acidified calcined palygorskite, 0.472 mol L-1 min-1 for Fe2O3/palygorskite and 1.276 mol L-1 min-1 for the sludge to char, the latter being the best catalyst for mineralization of acid to CO2 and water. The quinones were adsorbed to the acidic sites of the calcined palygorskite and Fe2O3/palygorskite whose adsorption constants were similar (~ 4.45 L mol-1) and higher than that of the sewage sludge char (3.77 L mol-1).

Avaliação do desempenho da paligorsquita modificada e do carvão da pirólise do lodo de esgoto no processo de degradação fotocatalítica do fenol

The uncontrolled disposal of wastewaters containing phenolic compounds by the industry has caused irreversible damage to the environment. Because of this, it is now mandatory to develop new methods to treat these effluents before they are disposed of. One of the most promising and low cost approaches is the degradation of phenolic compounds via photocatalysis. This work, in particular, has as the main goal, the customization of a bench scale photoreactor and the preparation of catalysts via utilization of char originated from the fast pyrolysis of sewage sludge. The experiments were carried out at constant temperature (50°C) under oxygen (410, 515, 650 and 750 ml min-1). The reaction took place in the liquid phase (3.4 liters), where the catalyst concentration was 1g L-1 and the initial concentration of phenol was 500 mg L-1 and the reaction time was set to 3 hours. A 400 W lamp was adapted to the reactor. The flow of oxygen was optimized to 650 ml min-1. The pH of the liquid and the nature of the catalyst (acidified and calcined palygorskite, palygorskite impregnated with 3.8% Fe and the pyrolysis char) were investigated. The catalytic materials were characterized by XRD, XRF, and BET. In the process of photocatalytic degradation of phenol, the results showed that the pH has a significant influence on the phenol conversion, with best results for pH equal to 5.5. The phenol conversion ranged from 51.78% for the char sewage sludge to 58.02% (for palygorskite acidified calcined). Liquid samples analyzed by liquid chromatography and the following compounds were identified: hydroquinone, catechol and maleic acid. A mechanism of the reaction was proposed, whereas the phenol is transformed into the homogeneous phase and the others react on the catalyst surface. For the latter, the Langmuir-Hinshelwood model was applied, whose mass balances led to a system of differential equations and these were solved using numerical methods in order to get estimates for the kinetic and adsorption parameters. The model was adjusted satisfactorily to the experimental results. From the proposed mechanism and the operating conditions used in this study, the most favored step, regardless of the catalyst, was the acid group (originated from quinone compounds), being transformed into CO2 and water, whose rate constant k4 presented value of 0.578 mol L-1 min-1 for acidified calcined palygorskite, 0.472 mol L-1 min-1 for Fe2O3/palygorskite and 1.276 mol L-1 min-1 for the sludge to char, the latter being the best catalyst for mineralization of acid to CO2 and water. The quinones were adsorbed to the acidic sites of the calcined palygorskite and Fe2O3/palygorskite whose adsorption constants were similar (~ 4.45 L mol-1) and higher than that of the sewage sludge char (3.77 L mol-1).

Modelagem da degradação de fenol em efluentes aquosos através do processo de foto-fenton

Advanced Oxidation Processes (AOP) are techniques involving the formation of hydroxyl radical (HO•) with high organic matter oxidation rate. These processes application in industry have been increasing due to their capacity of degrading recalcitrant substances that cannot be completely removed by traditional processes of effluent treatment. In the present work, phenol degrading by photo-Fenton process based on addition of H2O2, Fe2+ and luminous radiation was studied. An experimental design was developed to analyze the effect of phenol, H2O2 and Fe2+ concentration on the fraction of total organic carbon (TOC) degraded. The experiments were performed in a batch photochemical parabolic reactor with 1.5 L of capacity. Samples of the reactional medium were collected at different reaction times and analyzed in a TOC measurement instrument from Shimadzu (TOC-VWP). The results showed a negative effect of phenol concentration and a positive effect of the two other variables in the TOC degraded fraction. A statistical analysis of the experimental design showed that the hydrogen peroxide concentration was the most influent variable in the TOC degraded fraction at 45 minutes and generated a model with R² = 0.82, which predicted the experimental data with low precision. The Visual Basic for Application (VBA) tool was used to generate a neural networks model and a photochemical database. The aforementioned model presented R² = 0.96 and precisely predicted the response data used for testing. The results found indicate the possible application of the developed tool for industry, mainly for its simplicity, low cost and easy access to the program.

Modelagem da degradação de fenol em efluentes aquosos através do processo de foto-fenton

Advanced Oxidation Processes (AOP) are techniques involving the formation of hydroxyl radical (HO•) with high organic matter oxidation rate. These processes application in industry have been increasing due to their capacity of degrading recalcitrant substances that cannot be completely removed by traditional processes of effluent treatment. In the present work, phenol degrading by photo-Fenton process based on addition of H2O2, Fe2+ and luminous radiation was studied. An experimental design was developed to analyze the effect of phenol, H2O2 and Fe2+ concentration on the fraction of total organic carbon (TOC) degraded. The experiments were performed in a batch photochemical parabolic reactor with 1.5 L of capacity. Samples of the reactional medium were collected at different reaction times and analyzed in a TOC measurement instrument from Shimadzu (TOC-VWP). The results showed a negative effect of phenol concentration and a positive effect of the two other variables in the TOC degraded fraction. A statistical analysis of the experimental design showed that the hydrogen peroxide concentration was the most influent variable in the TOC degraded fraction at 45 minutes and generated a model with R² = 0.82, which predicted the experimental data with low precision. The Visual Basic for Application (VBA) tool was used to generate a neural networks model and a photochemical database. The aforementioned model presented R² = 0.96 and precisely predicted the response data used for testing. The results found indicate the possible application of the developed tool for industry, mainly for its simplicity, low cost and easy access to the program.

Degradação de paracetamol empregando tecnologia oxidativa avançada baseada em fotocatálise heterogênea usando irradiação artificial e solar

In this work, the oxidation and mineralization of paracetamol, based in an advanced oxidative process promoted by heterogeneous photocatalysis, was evaluated. The action of two photocatalysts (titanium dioxide, and a composite based on the association between titanium dioxide and zinc phthalocyanine dye) was studied. First of all, experiments in laboratory scale were performed using as radiation font a 400 W high pressure mercury lamp. The mineralization of paracetamol, promoted by both photocatalysts, was evaluated working with 4L of solution containing 10 mg L-1 of paracetamol and 100 mg L-1 of photocatalyst. To find the best experimental conditions, the influence of hydrogen peroxide concentration and pH was evaluated for the reactions. The best results for the reactions in laboratory scale was obtained using 33,00 mg L-1 of hydrogen peroxide in natural pH (6,80). Under these conditions, 100% oxidation was reached in just 40 minutes of reaction using TiO2 P25, while the mineralization was 78%. Using the composite, the mineralization was 63% in 2 hours of reaction and a oxidation of almost 100% was reached after 60 minutes. A CPC reactor (compound parabolic concentrator) was employed in the expanded work scale, using the sun as irradiation source. In this case the experiments were performed using 50 L of aqueous solution containing 10 mg L-1 of paracetamol and 100 mg L-1 of photocatalyst. The assays were done at pH 3,00 and natural pH (6,80). The used concentration of hydrogen peroxide was 33,00 mg L-1, adopted after laboratory scale studies. The reaction at pH 3,00 shows to be more advantageous, since under natural pH (6,80), the use of deionized water was necessary to prepare the solutions, probably because the deleterious action of carbonate ions, known hydroxyl radical scavengers. Using solar irradiation, the reaction mediated by the composite was more efficient when compared with the assays under laboratory scale since the composite presents the advantage of promoting a better use of visible radiation. Under these conditions, the mineralization increased from 40% to 56% under pH 3,00. At natural pH the oxidation occurred more slowly and the mineralization decreased from 56% to 50%. Thus, the use of pH 3,00 will be more interesting in real scale applications, even if it is necessary the pH correction before the discard of the treated effluent to the environment.

Estudo comparativo do processo de tratamento por lamas ativadas em regime de arejamento prolongado

Atualmente a despoluição das águas, antes da sua descarga em meio hídrico, é considerada uma necessidade de elevada importância, sendo realizada em Estações de Tratamento de Águas Residuais (ETAR). Dependendo da origem e das características de cada afluente, as ETAR adotam diversos tipos de tratamento, adequando-os caso a caso, com o objetivo de conseguir uma elevada qualidade para o efluente final. O tipo de tratamento mais utilizado, e também o mais versátil, é o tratamento biológico por lamas ativadas. Neste contexto, o presente trabalho apresenta um estudo comparativo do processo de tratamento biológico por lamas ativadas, em operação em regime de arejamento prolongado, aplicado a três estações de tratamento de águas residuais, com características distintas no que se refere ao tipo de reator biológico utilizado, assim como, ao volume e à sazonalidade do caudal a tratar. As ETAR contempladas no estudo, nomeadamente, a ETAR do Juncal, a ETAR de Pedreiras e a ETAR de Fátima, localizam-se no distrito de Leiria e fazem parte do Saneamento Integrado dos Municípios do Lis (SIMLIS). A comparação do processo de tratamento das ETAR decorreu entre Outubro de 2013 e Junho de 2014, tendo-se baseado na monitorização dos reatores biológicos, no que se refere ao pH, potencial redox, OD, temperatura, concentração de SST e SSV, teste de sedimentabilidade, IVL, razão A/M e A/V, TRH, TRS, cor das lamas e microbiologia. Os valores obtidos permitiram concluir que, num contexto geral, as três ETAR apenas demonstraram um comportamento ideal relativamente aos valores de pH e potencial redox. Os valores de OD e temperatura mantiveram-se abaixo dos valores ideais para este tipo de tratamento; e a elevada concentração de SSV, nas ETAR de Fátima e de Pedreiras, e a baixa concentração de SSV, na ETAR de Juncal, impediram que a razão A/M, o teste de sedimentabilidade o IVL e o TRS cumprissem os valores ideais esperados. O incumprimento dos valores recomendados deve-se, muito provavelmente, ao facto das ETAR se encontrarem a operar abaixo da sua capacidade de utilização, no que respeita à população-equivalente a servir e ao volume de caudal afluente. Aparentemente as condições operacionais observadas durante o estudo não condicionaram o processo de tratamento biológico, uma vez que a qualidade do efluente tratado manteve sempre padrões elevados

Perfil anaeróbico de futebolistas da segunda divisão do campeonato gaúcho

O futebol é um esporte cuja maioria das açoes durante a partida sao de alta intensidade e curta duraçao, sendo entao predominantemente composto de tiros de alta velocidade. O objetivo desse estudo é descrever o perfil de performance anaeróbica através de corrida maxíma de 30 metros de jogadores de futebol profissional da divisao de acesso do campeonato gaúcho. A escassez de dados em âmbito regional ressalta a importância deste estudo para futuras comparaçoes e preparaçao dos atletas que disputam essa competiçao. Foram avaliados através dos teste de corrida de 30 metros, 23 jogadores de Santa Maria-RS. A média de idade do grupo foi de 24,76±5,59 anos,a massa corporal de 80,6±9,7 kg, a estatura de 178,8±6,3 cm e o ?7DC 82,3±19,1mm. Os resultados apontam o tempo médio de corrida de 30 m. foi 4,06±0,32seg. Por posiçoes, os goleiros obtiveram na corrida de 30 m o tempo de 4,12±0,12 seg. Os zagueiros 4,22±0,37 seg. Os laterais 4,14±0,35 seg. Os volantes 4,05±0,26 seg. Os meio-campistas 3,97±0,36 seg. Os atacantes 4,02±0,17 seg. Os goleiros e os zagueiros tiveram os piores resultados comparados aos demais atletas, resultado esperado devido às características específicas da funçao

Capacidade de sprints de futebolistas na pré temporada

No futebol as corridas de alta velocidade em curto espaço e médias distâncias sao consideradas decisivas. O objetivo desse estudo foi investigar o nível de condicionamento anaeróbio de atletas, que disputam a divisao de acesso do campeonato gaúcho. O grupo estudado tinha a média de idade de 24,8±5,6 anos, massa corporal de 79,9±9,2 kg, estatura de 178,5±6,7 cm e o somatório de 7 dobras cutâneas 82±19,4 mm e foi composto por jogadores profissionais de futebol. Os resultados encontrados para potência absoluta em Watts(W) foram potência média 598,2±84,6 W; potência mínima 454±87,2 W e potência máxima 762,3±145 W. A potência média por posiçao resultante: atacantes: 673,3±22,2 W; laterais: 641,2±75,6 W; zagueiros 619,2±30,5 W; os volantes: 600±92,6 W e meias:539,6±94,3 W. Os resultados obtidos auxiliam na preparaçao física da equipe e colaboram para criaçao de um perfil dos jogadores de futebol da 2a divisao do RS

Perfil anaeróbico de futebolistas da segunda divisão do campeonato gaúcho

O futebol é um esporte cuja maioria das açoes durante a partida sao de alta intensidade e curta duraçao, sendo entao predominantemente composto de tiros de alta velocidade. O objetivo desse estudo é descrever o perfil de performance anaeróbica através de corrida maxíma de 30 metros de jogadores de futebol profissional da divisao de acesso do campeonato gaúcho. A escassez de dados em âmbito regional ressalta a importância deste estudo para futuras comparaçoes e preparaçao dos atletas que disputam essa competiçao. Foram avaliados através dos teste de corrida de 30 metros, 23 jogadores de Santa Maria-RS. A média de idade do grupo foi de 24,76±5,59 anos,a massa corporal de 80,6±9,7 kg, a estatura de 178,8±6,3 cm e o ?7DC 82,3±19,1mm. Os resultados apontam o tempo médio de corrida de 30 m. foi 4,06±0,32seg. Por posiçoes, os goleiros obtiveram na corrida de 30 m o tempo de 4,12±0,12 seg. Os zagueiros 4,22±0,37 seg. Os laterais 4,14±0,35 seg. Os volantes 4,05±0,26 seg. Os meio-campistas 3,97±0,36 seg. Os atacantes 4,02±0,17 seg. Os goleiros e os zagueiros tiveram os piores resultados comparados aos demais atletas, resultado esperado devido às características específicas da funçao

Capacidade de sprints de futebolistas na pré temporada

No futebol as corridas de alta velocidade em curto espaço e médias distâncias sao consideradas decisivas. O objetivo desse estudo foi investigar o nível de condicionamento anaeróbio de atletas, que disputam a divisao de acesso do campeonato gaúcho. O grupo estudado tinha a média de idade de 24,8±5,6 anos, massa corporal de 79,9±9,2 kg, estatura de 178,5±6,7 cm e o somatório de 7 dobras cutâneas 82±19,4 mm e foi composto por jogadores profissionais de futebol. Os resultados encontrados para potência absoluta em Watts(W) foram potência média 598,2±84,6 W; potência mínima 454±87,2 W e potência máxima 762,3±145 W. A potência média por posiçao resultante: atacantes: 673,3±22,2 W; laterais: 641,2±75,6 W; zagueiros 619,2±30,5 W; os volantes: 600±92,6 W e meias:539,6±94,3 W. Os resultados obtidos auxiliam na preparaçao física da equipe e colaboram para criaçao de um perfil dos jogadores de futebol da 2a divisao do RS

Perfil anaeróbico de futebolistas da segunda divisão do campeonato gaúcho

O futebol é um esporte cuja maioria das açoes durante a partida sao de alta intensidade e curta duraçao, sendo entao predominantemente composto de tiros de alta velocidade. O objetivo desse estudo é descrever o perfil de performance anaeróbica através de corrida maxíma de 30 metros de jogadores de futebol profissional da divisao de acesso do campeonato gaúcho. A escassez de dados em âmbito regional ressalta a importância deste estudo para futuras comparaçoes e preparaçao dos atletas que disputam essa competiçao. Foram avaliados através dos teste de corrida de 30 metros, 23 jogadores de Santa Maria-RS. A média de idade do grupo foi de 24,76±5,59 anos,a massa corporal de 80,6±9,7 kg, a estatura de 178,8±6,3 cm e o ?7DC 82,3±19,1mm. Os resultados apontam o tempo médio de corrida de 30 m. foi 4,06±0,32seg. Por posiçoes, os goleiros obtiveram na corrida de 30 m o tempo de 4,12±0,12 seg. Os zagueiros 4,22±0,37 seg. Os laterais 4,14±0,35 seg. Os volantes 4,05±0,26 seg. Os meio-campistas 3,97±0,36 seg. Os atacantes 4,02±0,17 seg. Os goleiros e os zagueiros tiveram os piores resultados comparados aos demais atletas, resultado esperado devido às características específicas da funçao

Capacidade de sprints de futebolistas na pré temporada

No futebol as corridas de alta velocidade em curto espaço e médias distâncias sao consideradas decisivas. O objetivo desse estudo foi investigar o nível de condicionamento anaeróbio de atletas, que disputam a divisao de acesso do campeonato gaúcho. O grupo estudado tinha a média de idade de 24,8±5,6 anos, massa corporal de 79,9±9,2 kg, estatura de 178,5±6,7 cm e o somatório de 7 dobras cutâneas 82±19,4 mm e foi composto por jogadores profissionais de futebol. Os resultados encontrados para potência absoluta em Watts(W) foram potência média 598,2±84,6 W; potência mínima 454±87,2 W e potência máxima 762,3±145 W. A potência média por posiçao resultante: atacantes: 673,3±22,2 W; laterais: 641,2±75,6 W; zagueiros 619,2±30,5 W; os volantes: 600±92,6 W e meias:539,6±94,3 W. Os resultados obtidos auxiliam na preparaçao física da equipe e colaboram para criaçao de um perfil dos jogadores de futebol da 2a divisao do RS

Biocatálise aplicada à valorização de óleos alimentares usados

O crescente consumo de energia, bem como a possibilidade de esgotamento dos recursos não renováveis, tem fomentado a busca de fontes de energia alternativas. O biodiesel é um biocombustível obtido a partir de fontes renováveis e a sua utilização permite reduzir as emissões de gases com efeito de estufa. Nos últimos anos tem-se produzido biodiesel a partir de óleos alimentares usados (OAU), sendo que com esta aplicação valoriza-se um resíduo e simultaneamente produz-se um combustível “verde”. O biodiesel é produzido através das reações de transesterificação e/ou esterificação entre triglicerídeos e/ou ácidos gordos livres e um álcool, na presença de um catalisador. O rendimento do processo está estritamente relacionado com o tipo de catalisador e as condições que este opera. O principal objetivo do presente trabalho consistiu na avaliação do efeito de alguns parâmetros operacionais no desempenho de uma lípase imobilizada (Novozyme® 435), nomeadamente: (i) índice de acidez do óleo, (ii) razão mássica de enzima/óleo e (iii) método regeneração da enzima com vista à sua reutilização. Também foi objeto de estudo do presente trabalho a produção em contínuo, num (bior)reator tubular de leito fixo, de ésteres metílicos de ácidos gordos (FAME) usando a referida enzima. Registou-se um aumento rendimento em com o incremento do índice de acidez do óleo usado, o que indicia que a enzima catalisa simultaneamente as reações de esterificação e transesterificação. Relativamente à razão mássica de enzima/óleo, dentro da gama testada verificou-se um aumento do rendimento em FAME com a concentração da enzima em meio reacional. Dos vários solventes testados, a aplicação de solvente tert-butanol na regeneração (com incubação) da enzima foi o que melhores resultados teve. Finalmente, os resultados obtidos no ensaio de produção de FAME num biorreator contínuo são motivadores, criando expectativas de uma possível aplicação industrial no futuro.