28 research outputs found

    Análise do processo de pirólise de sementes de Açaí (Euterpe Oleracea, Mart): Influência da temperatura no rendimento dos produtos de reação e nas propriedades físico-químicas do Bio-Óleo / Process analysis of pyrolise of Açaí (Euterpe Oleracea, Mart) seeds: Influence of temperature on the yield of reaction products and physico-chemical properties of Bio-Oil

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    Neste trabalho, investigou-se a influência da temperatura no rendimento de produtos de reação (bio-óleo, gás,  e coque) e nas propriedades físico-químicas (índice de acidez, densidade e viscosidade cinemática) do bio-óleo obtido via pirólise de sementes de Açaí (Euterpe oleracea, Mart.), um resíduo rico em lignina-celulose, em escala piloto. A reação de pirólise foi realizada em reator de 143 L, operando em modo batelada a 350, 400 e 450 ºC, 1,0 atmosfera. O bio-óleo foi caracterizado físico-quimicamente em termos de densidade, viscosidade cinemática, índice de acidez e índice de refração. Os rendimentos do bio-óleo, , e gás variaram entre 2,0 e 4,39% (em peso), 26,58 e 29,39% (em peso) e 18,76 e 30,56% (em peso), respectivamente, aumentando com a temperatura do processo, enquanto que da fase sólida (coque) variou entre 35,67 e 52,67% (em peso), diminuindo com a temperatura. As densidades de bio-óleo e viscosidades cinemáticas variaram entre 1,0236 e 1,0468 g/cm³ e 57,22 e 68,34 mm²/s, respectivamente, aumentado com a temperatura, enquanto que os índices de acidez do bio-óleo variaram entre 70,26 e 92,87 mg KOH/g, diminuindo com a temperatura. 

    Fractional Distillation of Bio-Oil Produced by Pyrolysis of Açaí (Euterpe oleracea) Seeds

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    In this work, the seeds of açaí (Euterpe oleracea, Mart), a rich lignin-cellulose residue, has been submitted to pyrolysis to produce a bio-oil-like fossil fuels. The pyrolysis carried out in a reactor of 143 L, 450°C, and 1.0 atm. The morphology of Açaí seeds in nature and after pyrolysis is characterized by SEM, EDX, and XRD. The experiments show that bio-oil, gas, and coke yields were 4.38, 30.56, and 35.67% (wt.), respectively. The bio-oil characterized by AOCS, ASTM, and ABNT/NBR methods for density, kinematic viscosity, and acid value. The bio-oil density, viscosity, and acid value were 1.0468 g/cm3, 68.34 mm2/s, and 70.26 KOH/g, respectively. The chemical composition and chemical functions of bio-oil are determined by GC-MS and FT-IR. The GC-MS identified in bio-oil 21.52% (wt.) hydrocarbons and 78.48% (wt.) oxygenates (4.06% esters, 8.52% carboxylic acids, 3.53% ketones, 35.16% phenols, 20.52% cresols, 5.75% furans, and 0.91% (wt.) aldehydes), making it possible to apply fractional distillation to obtain fossil fuel-like fractions rich in hydrocarbons. The distillation of bio-oil is carried out in a laboratory-scale column, according to the boiling temperature of fossil fuels. The distillation of bio-oil yielded fossil fuel-like fractions (gasoline, kerosene, and light diesel) of 4.70, 28.21, and 22.35% (wt.), respectively

    Análise da composição química do Bio-Óleo produzido via pirólise de sementes de Açaí (Euterpe Oleracea, Mart) / Chemical analysis of Bio-Oil produced by pyrolise of Açaí (Euterpe Oleracea, Mart) seeds

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    Neste trabalho, a influência da temperatura na composição química (hidrocarbonetos e produtos oxigenados) do bio-óleo obtido via pirólise de sementes do Açaí (Euterpe oleracea, Mart.), um resíduo rico em lignina-celulose, foi sistematicamente investigada em escala piloto. A reação de pirólise foi realizada em reator de 143 L, operando em modo batelada a 350, 400 e 450 ºC, 1,0 atmosfera. A composição química e a análise qualitativa das funções e/ou grupos presentes no bio-óleo foram determinadas por GC-MS e FT-IR. A análise de FT-IR identificou funções químicas características de hidrocarbonetos (alcanos, alcenos e aromáticos) e oxigenados (fenóis, cresóis, cetonas, ésteres, ácidos carboxílicos, aldeídos e furanos) no bio-óleo. A análise de GC-MS identificou hidrocarbonetos e oxigenados como principais compostos químicos do bio-óleo, com composição química fortemente dependentes da temperatura de pirólise. A concentração de hidrocarbonetos no bio-óleo variou entre 13,505 e 21,542% (área.), aumentando com a temperatura, enquanto a dos produtos oxigenados variaram entre 78,458 e 86,495% (área.), diminui com a temperatura de pirólise. A composição de alcanos, alcenos e aromáticos aumenta com a temperatura, mostrando que temperaturas mais altas favorecem a formação de hidrocarbonetos

    Degradação térmica de resíduos de resinas dentárias reticuladas a base de PMMA: Recuperação do MMA / Thermal degradation of cross-linked PMMA-based dental resins scraps: Recovery of MMA

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    Neste trabalho, os resíduos de resina dentária reticulado a base de PMMA, foi submetido a pirólise para recuperar o MMA (Metilmetacrilato). A degradação térmica de resíduos de resinas dentárias à base de PMMA reticulado, foi analisada por termo-gravimetria (TG) e termo-gravimetria derivada (DTG) para orientar as condições de operação em escala piloto. A pirólise foi realizada em um reator de 143L, a 420°C e 1,0 atm. A composição química da reação de produtos líquidos de reação obtidos a 420°C, 40, 60, 80, 100, 110 e 130 minutos determinados por cromatografia gasosa acoplada à espectrometria de massas (GC-MS). O rendimento da fase líquida foi 48.20% (m./m.), enquanto o da fase gasosa foi 40.13% (m./m.). O GC-MS identificou nos produtos líquidos de reação a 420°C e 1,0 atm, ésteres do ácido acrílico e cetonas, mostrando concentrações de MMA (Metilmetacrilato) entre 94.51 e 98.85% (área). As concentrações de MMA (Metilmetacrilato) na fase líquida, entre 40 e 80 minutos, alcançaram purezas acima de 98% (área), diminuindo com o aumento do tempo de reação após 100 minutos, tornando assim possível despolimerizar os resíduos de resinas dentais reticuladas à base de PMMA por pirólise para recuperar o MMA (Metilmetacrilato)

    Worldwide trends in hypertension prevalence and progress in treatment and control from 1990 to 2019: a pooled analysis of 1201 population-representative studies with 104 million participants.

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    BACKGROUND: Hypertension can be detected at the primary health-care level and low-cost treatments can effectively control hypertension. We aimed to measure the prevalence of hypertension and progress in its detection, treatment, and control from 1990 to 2019 for 200 countries and territories. METHODS: We used data from 1990 to 2019 on people aged 30-79 years from population-representative studies with measurement of blood pressure and data on blood pressure treatment. We defined hypertension as having systolic blood pressure 140 mm Hg or greater, diastolic blood pressure 90 mm Hg or greater, or taking medication for hypertension. We applied a Bayesian hierarchical model to estimate the prevalence of hypertension and the proportion of people with hypertension who had a previous diagnosis (detection), who were taking medication for hypertension (treatment), and whose hypertension was controlled to below 140/90 mm Hg (control). The model allowed for trends over time to be non-linear and to vary by age. FINDINGS: The number of people aged 30-79 years with hypertension doubled from 1990 to 2019, from 331 (95% credible interval 306-359) million women and 317 (292-344) million men in 1990 to 626 (584-668) million women and 652 (604-698) million men in 2019, despite stable global age-standardised prevalence. In 2019, age-standardised hypertension prevalence was lowest in Canada and Peru for both men and women; in Taiwan, South Korea, Japan, and some countries in western Europe including Switzerland, Spain, and the UK for women; and in several low-income and middle-income countries such as Eritrea, Bangladesh, Ethiopia, and Solomon Islands for men. Hypertension prevalence surpassed 50% for women in two countries and men in nine countries, in central and eastern Europe, central Asia, Oceania, and Latin America. Globally, 59% (55-62) of women and 49% (46-52) of men with hypertension reported a previous diagnosis of hypertension in 2019, and 47% (43-51) of women and 38% (35-41) of men were treated. Control rates among people with hypertension in 2019 were 23% (20-27) for women and 18% (16-21) for men. In 2019, treatment and control rates were highest in South Korea, Canada, and Iceland (treatment >70%; control >50%), followed by the USA, Costa Rica, Germany, Portugal, and Taiwan. Treatment rates were less than 25% for women and less than 20% for men in Nepal, Indonesia, and some countries in sub-Saharan Africa and Oceania. Control rates were below 10% for women and men in these countries and for men in some countries in north Africa, central and south Asia, and eastern Europe. Treatment and control rates have improved in most countries since 1990, but we found little change in most countries in sub-Saharan Africa and Oceania. Improvements were largest in high-income countries, central Europe, and some upper-middle-income and recently high-income countries including Costa Rica, Taiwan, Kazakhstan, South Africa, Brazil, Chile, Turkey, and Iran. INTERPRETATION: Improvements in the detection, treatment, and control of hypertension have varied substantially across countries, with some middle-income countries now outperforming most high-income nations. The dual approach of reducing hypertension prevalence through primary prevention and enhancing its treatment and control is achievable not only in high-income countries but also in low-income and middle-income settings. FUNDING: WHO

    Worldwide trends in hypertension prevalence and progress in treatment and control from 1990 to 2019: a pooled analysis of 1201 population-representative studies with 104 million participants

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    Background Hypertension can be detected at the primary health-care level and low-cost treatments can effectively control hypertension. We aimed to measure the prevalence of hypertension and progress in its detection, treatment, and control from 1990 to 2019 for 200 countries and territories. Methods We used data from 1990 to 2019 on people aged 30-79 years from population-representative studies with measurement of blood pressure and data on blood pressure treatment. We defined hypertension as having systolic blood pressure 140 mm Hg or greater, diastolic blood pressure 90 mm Hg or greater, or taking medication for hypertension. We applied a Bayesian hierarchical model to estimate the prevalence of hypertension and the proportion of people with hypertension who had a previous diagnosis (detection), who were taking medication for hypertension (treatment), and whose hypertension was controlled to below 140/90 mm Hg (control). The model allowed for trends over time to be non-linear and to vary by age. Findings The number of people aged 30-79 years with hypertension doubled from 1990 to 2019, from 331 (95% credible interval 306-359) million women and 317 (292-344) million men in 1990 to 626 (584-668) million women and 652 (604-698) million men in 2019, despite stable global age-standardised prevalence. In 2019, age-standardised hypertension prevalence was lowest in Canada and Peru for both men and women; in Taiwan, South Korea, Japan, and some countries in western Europe including Switzerland, Spain, and the UK for women; and in several low-income and middle-income countries such as Eritrea, Bangladesh, Ethiopia, and Solomon Islands for men. Hypertension prevalence surpassed 50% for women in two countries and men in nine countries, in central and eastern Europe, central Asia, Oceania, and Latin America. Globally, 59% (55-62) of women and 49% (46-52) of men with hypertension reported a previous diagnosis of hypertension in 2019, and 47% (43-51) of women and 38% (35-41) of men were treated. Control rates among people with hypertension in 2019 were 23% (20-27) for women and 18% (16-21) for men. In 2019, treatment and control rates were highest in South Korea, Canada, and Iceland (treatment >70%; control >50%), followed by the USA, Costa Rica, Germany, Portugal, and Taiwan. Treatment rates were less than 25% for women and less than 20% for men in Nepal, Indonesia, and some countries in sub-Saharan Africa and Oceania. Control rates were below 10% for women and men in these countries and for men in some countries in north Africa, central and south Asia, and eastern Europe. Treatment and control rates have improved in most countries since 1990, but we found little change in most countries in sub-Saharan Africa and Oceania. Improvements were largest in high-income countries, central Europe, and some upper-middle-income and recently high-income countries including Costa Rica, Taiwan, Kazakhstan, South Africa, Brazil, Chile, Turkey, and Iran. Interpretation Improvements in the detection, treatment, and control of hypertension have varied substantially across countries, with some middle-income countries now outperforming most high-income nations. The dual approach of reducing hypertension prevalence through primary prevention and enhancing its treatment and control is achievable not only in high-income countries but also in low-income and middle-income settings. Copyright (C) 2021 World Health Organization; licensee Elsevier

    Worldwide trends in hypertension prevalence and progress in treatment and control from 1990 to 2019: a pooled analysis of 1201 population-representative studies with 104 million participants

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    Background Hypertension can be detected at the primary health-care level and low-cost treatments can effectively control hypertension. We aimed to measure the prevalence of hypertension and progress in its detection, treatment, and control from 1990 to 2019 for 200 countries and territories. Methods We used data from 1990 to 2019 on people aged 30–79 years from population-representative studies with measurement of blood pressure and data on blood pressure treatment. We defined hypertension as having systolic blood pressure 140 mm Hg or greater, diastolic blood pressure 90 mm Hg or greater, or taking medication for hypertension. We applied a Bayesian hierarchical model to estimate the prevalence of hypertension and the proportion of people with hypertension who had a previous diagnosis (detection), who were taking medication for hypertension (treatment), and whose hypertension was controlled to below 140/90 mm Hg (control). The model allowed for trends over time to be non-linear and to vary by age. Findings The number of people aged 30–79 years with hypertension doubled from 1990 to 2019, from 331 (95% credible interval 306–359) million women and 317 (292–344) million men in 1990 to 626 (584–668) million women and 652 (604–698) million men in 2019, despite stable global age-standardised prevalence. In 2019, age-standardised hypertension prevalence was lowest in Canada and Peru for both men and women; in Taiwan, South Korea, Japan, and some countries in western Europe including Switzerland, Spain, and the UK for women; and in several low-income and middle-income countries such as Eritrea, Bangladesh, Ethiopia, and Solomon Islands for men. Hypertension prevalence surpassed 50% for women in two countries and men in nine countries, in central and eastern Europe, central Asia, Oceania, and Latin America. Globally, 59% (55–62) of women and 49% (46–52) of men with hypertension reported a previous diagnosis of hypertension in 2019, and 47% (43–51) of women and 38% (35–41) of men were treated. Control rates among people with hypertension in 2019 were 23% (20–27) for women and 18% (16–21) for men. In 2019, treatment and control rates were highest in South Korea, Canada, and Iceland (treatment >70%; control >50%), followed by the USA, Costa Rica, Germany, Portugal, and Taiwan. Treatment rates were less than 25% for women and less than 20% for men in Nepal, Indonesia, and some countries in sub-Saharan Africa and Oceania. Control rates were below 10% for women and men in these countries and for men in some countries in north Africa, central and south Asia, and eastern Europe. Treatment and control rates have improved in most countries since 1990, but we found little change in most countries in sub-Saharan Africa and Oceania. Improvements were largest in high-income countries, central Europe, and some upper-middle-income and recently high-income countries including Costa Rica, Taiwan, Kazakhstan, South Africa, Brazil, Chile, Turkey, and Iran. Interpretation Improvements in the detection, treatment, and control of hypertension have varied substantially across countries, with some middle-income countries now outperforming most high-income nations. The dual approach of reducing hypertension prevalence through primary prevention and enhancing its treatment and control is achievable not only in high-income countries but also in low-income and middle-income settings

    Worldwide trends in hypertension prevalence and progress in treatment and control from 1990 to 2019: a pooled analysis of 1201 population-representative studies with 104 million participants

    Get PDF
    Background Hypertension can be detected at the primary health-care level and low-cost treatments can effectively control hypertension. We aimed to measure the prevalence of hypertension and progress in its detection, treatment, and control from 1990 to 2019 for 200 countries and territories. Methods We used data from 1990 to 2019 on people aged 30–79 years from population-representative studies with measurement of blood pressure and data on blood pressure treatment. We defined hypertension as having systolic blood pressure 140 mm Hg or greater, diastolic blood pressure 90 mm Hg or greater, or taking medication for hypertension. We applied a Bayesian hierarchical model to estimate the prevalence of hypertension and the proportion of people with hypertension who had a previous diagnosis (detection), who were taking medication for hypertension (treatment), and whose hypertension was controlled to below 140/90 mm Hg (control). The model allowed for trends over time to be non-linear and to vary by age. Findings The number of people aged 30–79 years with hypertension doubled from 1990 to 2019, from 331 (95% credible interval 306–359) million women and 317 (292–344) million men in 1990 to 626 (584–668) million women and 652 (604–698) million men in 2019, despite stable global age-standardised prevalence. In 2019, age-standardised hypertension prevalence was lowest in Canada and Peru for both men and women; in Taiwan, South Korea, Japan, and some countries in western Europe including Switzerland, Spain, and the UK for women; and in several low-income and middle-income countries such as Eritrea, Bangladesh, Ethiopia, and Solomon Islands for men. Hypertension prevalence surpassed 50% for women in two countries and men in nine countries, in central and eastern Europe, central Asia, Oceania, and Latin America. Globally, 59% (55–62) of women and 49% (46–52) of men with hypertension reported a previous diagnosis of hypertension in 2019, and 47% (43–51) of women and 38% (35–41) of men were treated. Control rates among people with hypertension in 2019 were 23% (20–27) for women and 18% (16–21) for men. In 2019, treatment and control rates were highest in South Korea, Canada, and Iceland (treatment >70%; control >50%), followed by the USA, Costa Rica, Germany, Portugal, and Taiwan. Treatment rates were less than 25% for women and less than 20% for men in Nepal, Indonesia, and some countries in sub-Saharan Africa and Oceania. Control rates were below 10% for women and men in these countries and for men in some countries in north Africa, central and south Asia, and eastern Europe. Treatment and control rates have improved in most countries since 1990, but we found little change in most countries in sub-Saharan Africa and Oceania. Improvements were largest in high-income countries, central Europe, and some upper-middle-income and recently high-income countries including Costa Rica, Taiwan, Kazakhstan, South Africa, Brazil, Chile, Turkey, and Iran. Interpretation Improvements in the detection, treatment, and control of hypertension have varied substantially across countries, with some middle-income countries now outperforming most high-income nations. The dual approach of reducing hypertension prevalence through primary prevention and enhancing its treatment and control is achievable not only in high-income countries but also in low-income and middle-income settings

    Estudo comparativo dos processos de separação na obtenção do biodiesel de óleo de palma bruto (Elaeis guineensis, Jacq)

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    This work investigated the influence of the separation processes on the yield and properties relating to the quality of biodiesel from crude palm oil ( Elaeis guineensis, Jacq ) obtained in laboratory scale , such as decantation , centrifugation , evaporation , washing and dehydration, where the following operating conditions are used : the settling time ( sludge/neutral oil ) - 120 minutes at 50 ° C; settling time used for washing the neutral oil 60, 90 and 120 minutes at 50 °C; H2O percentages used in washing the neutral oil 10%, 20% and 30% ( m./m.); temperatures centrifugation for separating the neutral/oil sludge and washings neutral oil 40, 50 and 60 °C; temperature and pressure range of dehydration of neutral oil and biodiesel and 80 °C from 480,0 to 80,0 mbar respectively; temperature and pressure in the evaporation of excess ethanol 75 °C and 213,3 and 146,6 respectively March; the settling time of biodiesel/glycerol system and washes 60, 90 and 180 minutes at 50 °C; operating temperature used in the centrifuge separation system biodiesel/glycerin 50 °C; H2O percentage of biodiesel used for washing by centrifugation 20% relative to the ester phase. The results found that neutralization in general was satisfactory as generated about 10% of blurs, highlighting the Experiment 1 that generated about 84,6% by weight of neutral oil. Washes in 90 minutes (Exp. 1) and 20% water (exp.2) showed the best performance for the separation by settling, while in the process of centrifugation and washing better separation occurred at 40 and 50 ° C respectively. In relation to the evaporation of ethanol, the best percentage in alcohol was obtained at 80 °C and 1466 mbar. Regarding the separation of phases rich in glycerol esters and the process of centrifugation at 50 °C led to a better quality biodiesel, however, the best yields were observed in the biodiesel from the settling process. The final evaluation of the biodiesel produced in this study was positive, because most of the analyzed parameters is according to the official specifications.CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorCNPq - Conselho Nacional de Desenvolvimento Científico e TecnológicoNeste trabalho investigou-se a influência dos processos de separação sobre o rendimento e as propriedades relativas à qualidade do biodiesel de óleo de palma bruto (Elaeis guineensis, Jacq) obtido em escala laboratorial, tais como decantação, centrifugação, evaporação, lavagem e desidratação, onde se utilizou as seguintes condições operacionais: tempo de decantação (borra/óleo neutro) – 120 minutos a 50 °C; tempos de decantação utilizados na lavagem do óleo neutro 60, 90 e 120 minutos a 50 °C; percentagens de H2O utilizadas na lavagem do óleo neutro 10%, 20% e 30% (m/m); temperaturas de centrifugação para separação do óleo neutro/borra e lavagens do óleo neutro 40, 50 e 60 °C; temperatura e faixa de pressão de desidratação do óleo neutro e do biodiesel 80 °C e 480,0 a 80,0 mbar respectivamente; temperatura e pressões de evaporação do etanol em excesso 75 °C e 213,3 e 146,6 mar respectivamente; tempos de decantação do sistema biodiesel/glicerina e de lavagens 60, 90 e 180 minutos a 50 °C; temperatura de operação utilizada na centrifugação na separação do sistema biodiesel/glicerina 50 °C; porcentagem de H2O utilizada na lavagem do biodiesel por centrifugação 20% em relação à fase éster. Os resultados constataram que a neutralização, em geral, foi satisfatória, pois gerou cerca de 10% de borra, ressaltando o Experimento 1 que gerou cerca de 84,6% em massa de óleo neutro. As lavagens em 90 minutos (Exp. 1) e com 20% em água (Exp.2) apresentaram os melhores desempenhos para a separação por decantação, enquanto que para o processo de centrifugação a melhor separação e lavagem ocorreram a 40 e 50 °C respectivamente. Em relação à evaporação do etanol, o melhor percentual em álcool foi obtido a 80 ºC e 146,6 mbar. Em relação à separação das fases ricas em ésteres e glicerol, o processo de centrifugação a 50 ºC gerou um biodiesel de melhor qualidade, entretanto, os melhores rendimentos se observaram no biodiesel proveniente do processo de decantação. A avaliação final do biodiesel produzido neste trabalho mostrou-se positiva, pois a maioria dos parâmetros analisados encontra-se de acordo com as especificações oficiais

    HIDRÓLISE ENZIMÁTICA DO CAROÇO DE AÇAÍ (Euterpe oleracea Mart) PARA A PRODUÇÃO DE ETANOL

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    O aproveitamento do caroço de Açaí (Euterpe oleracea Mart), com fins energéticos tem sido pouco estudado, por tanto buscou-se nesse artigo estudar a produção de etanol de segunda geração a partir da hidrólise enzimática do caroço de açaí in natura e tratado com solvente em duas condições de temperaturas (60 e 70 °C). Como resultados do processo de hidrólise enzimática, o caroço de açaí sem tratamento na temperatura de 60 °C (CANT60) mostrou ser uma biomassa lignocelulósica promissora para a obtenção de etanol, por conter um alto teor de celulose (40,29%), além de apresentar bons rendimentos na liberação de glicose (13,687 g.L-1) após a hidrólise enzimática. No tratamento com solvente do caroço de açaí (CAT), na conversão de celulose em glicose, o rendimento ficou abaixo de 25%, nas duas condições de temperaturas (60 e 70 °C), não foi capaz de desestruturar a parede vegetal da biomassa, em especial, celulose, hemicelulose e lignina. Mediante a análise dos dados experimentais, podemos dizer que a melhor condição da hidrólise enzimática do caroço de açaí foi o CANT60 com rendimentos de 84,54% em relação a concentração inicial de celulose e de 34,08% em relação a concentração inicial da polpa do caroço de açaí (40 g.L-1). A glicose obtida pela hidrólise enzimática do caroço de açaí foi bem assimilada pela levedura Saccharomyces cerevisiae para a produção de etanol, o rendimento, correspondeu a 87,08% em relação a concentração inicial de glicose (13,68 g.L-1)
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