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Masoud Asadieraghi - One of the best experts on this subject based on the ideXlab platform.
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characterization of lignocellulosic biomass thermal degradation and physiochemical structure effects of demineralization by diverse Acid solutions
Energy Conversion and Management, 2014Co-Authors: Masoud Asadieraghi, Wan Mohd Ashri Wan DaudAbstract:Abstract To eliminate the negative impacts of inorganic constituents during biomass thermochemical processes, leaching method by different Diluted Acid solutions was chosen. The different palm oil biomass samples (palm kernel shell (PKS), empty fruit bunches (EFB) and palm mesocarp fiber (PMF)) were pretreated by various Diluted Acid solutions (H2SO4, HClO4, HF, HNO3, HCl). Acids with the highest degrees of demineralization were selected to investigate the dematerialization impacts on the biomass thermal characteristics and physiochemical structure. Thermogravimetric analysis coupled with mass spectroscopy (TGA-MS) and Fourier transform infrared spectroscopy (TGA-FTIR) were employed to examine the biomass thermal degradation. TGA and DTG (Derivative thermogravimetry) indicated that the maximum degradation temperatures increased after Acid pretreatment due to the minerals catalytic effects. The main permanent evolved gases comprising H2, CO2, CO were detected online during analysis. The major permanent gases produced at the temperature range of 250–750 °C were attributed to the condensable vapors cracking and probably some secondary reactions. The physiochemical structure change of the Acid-treated biomass samples was examined by using Brunauer Emmett Teller (BET) method, Scanning Electron Microscope (SEM) and FTIR. The pyrolysis kinetics of the different palm oil biomasses were investigated using first order reaction model.
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characterization of lignocellulosic biomass thermal degradation and physiochemical structure effects of demineralization by diverse Acid solutions
Energy Conversion and Management, 2014Co-Authors: Masoud Asadieraghi, Wan Mohd Ashri Wan DaudAbstract:Abstract To eliminate the negative impacts of inorganic constituents during biomass thermochemical processes, leaching method by different Diluted Acid solutions was chosen. The different palm oil biomass samples (palm kernel shell (PKS), empty fruit bunches (EFB) and palm mesocarp fiber (PMF)) were pretreated by various Diluted Acid solutions (H2SO4, HClO4, HF, HNO3, HCl). Acids with the highest degrees of demineralization were selected to investigate the dematerialization impacts on the biomass thermal characteristics and physiochemical structure. Thermogravimetric analysis coupled with mass spectroscopy (TGA-MS) and Fourier transform infrared spectroscopy (TGA-FTIR) were employed to examine the biomass thermal degradation. TGA and DTG (Derivative thermogravimetry) indicated that the maximum degradation temperatures increased after Acid pretreatment due to the minerals catalytic effects. The main permanent evolved gases comprising H2, CO2, CO were detected online during analysis. The major permanent gases produced at the temperature range of 250–750 °C were attributed to the condensable vapors cracking and probably some secondary reactions. The physiochemical structure change of the Acid-treated biomass samples was examined by using Brunauer Emmett Teller (BET) method, Scanning Electron Microscope (SEM) and FTIR. The pyrolysis kinetics of the different palm oil biomasses were investigated using first order reaction model.
Paolo Pastore - One of the best experts on this subject based on the ideXlab platform.
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formation of volatile iodine compounds under hot concentrated Acid conditions nitric Acid or aqua regia and in Diluted Acid solutions with or without thiocyanate
Polyhedron, 2017Co-Authors: Denis Badocco, Francesca Romanini, Valerio Di Marco, Andrea Mondin, Paolo PastoreAbstract:Abstract It is reported that iodine volatilization can occur in any elemental analysis of total iodine by ICP-MS. This problem affects the accuracy of the results, and it has been neither rationalized nor solved up to now. In this work, the formation of volatile iodine compounds in concentrated Acid solutions (nitric Acid or aqua regia) under microwave heating was studied by UV–Vis spectrophotometry, linear sweep voltammetry, and cyclic voltammetry. It was evidenced that molecular iodine (I2) can unexpectedly form in concentrated hot HNO3 solutions, irrespective of the starting iodine compound (iodide, iodate, periodate, 3-iodo- l -tyrosine, 3,5-diiodo- l -tyrosine dehydrate). I2 is produced by the nitrogen oxides existing in these conditions. The formation of volatile iodine is minimized in aqua regia, as chloride is able to keep iodine in solution due to the formation of charged chloro-iodo complexes (e.g. I2Cl−). The dilution of the concentrated Acid solution, required prior to the ICP-MS analysis, causes the disruption of I2Cl− so that I2 can again volatilize. To avoid this, 0.1 M thiocyanate can be added, as it forms a strong I2SCN− complex which keeps I2 in solution as ion. Also other iodine species possibly occurring in the explored conditions, iodide and iodate, were demonstrated to be converted to I2SCN− in Diluted HNO3 solutions and in the presence of 0.1 M thiocyanate. Recovery tests demonstrated that iodine volatilization is minimized if samples containing iodine are treated in aqua regia and, after dilution, they are added with 0.1 M thiocyanate.
Wan Mohd Ashri Wan Daud - One of the best experts on this subject based on the ideXlab platform.
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characterization of lignocellulosic biomass thermal degradation and physiochemical structure effects of demineralization by diverse Acid solutions
Energy Conversion and Management, 2014Co-Authors: Masoud Asadieraghi, Wan Mohd Ashri Wan DaudAbstract:Abstract To eliminate the negative impacts of inorganic constituents during biomass thermochemical processes, leaching method by different Diluted Acid solutions was chosen. The different palm oil biomass samples (palm kernel shell (PKS), empty fruit bunches (EFB) and palm mesocarp fiber (PMF)) were pretreated by various Diluted Acid solutions (H2SO4, HClO4, HF, HNO3, HCl). Acids with the highest degrees of demineralization were selected to investigate the dematerialization impacts on the biomass thermal characteristics and physiochemical structure. Thermogravimetric analysis coupled with mass spectroscopy (TGA-MS) and Fourier transform infrared spectroscopy (TGA-FTIR) were employed to examine the biomass thermal degradation. TGA and DTG (Derivative thermogravimetry) indicated that the maximum degradation temperatures increased after Acid pretreatment due to the minerals catalytic effects. The main permanent evolved gases comprising H2, CO2, CO were detected online during analysis. The major permanent gases produced at the temperature range of 250–750 °C were attributed to the condensable vapors cracking and probably some secondary reactions. The physiochemical structure change of the Acid-treated biomass samples was examined by using Brunauer Emmett Teller (BET) method, Scanning Electron Microscope (SEM) and FTIR. The pyrolysis kinetics of the different palm oil biomasses were investigated using first order reaction model.
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characterization of lignocellulosic biomass thermal degradation and physiochemical structure effects of demineralization by diverse Acid solutions
Energy Conversion and Management, 2014Co-Authors: Masoud Asadieraghi, Wan Mohd Ashri Wan DaudAbstract:Abstract To eliminate the negative impacts of inorganic constituents during biomass thermochemical processes, leaching method by different Diluted Acid solutions was chosen. The different palm oil biomass samples (palm kernel shell (PKS), empty fruit bunches (EFB) and palm mesocarp fiber (PMF)) were pretreated by various Diluted Acid solutions (H2SO4, HClO4, HF, HNO3, HCl). Acids with the highest degrees of demineralization were selected to investigate the dematerialization impacts on the biomass thermal characteristics and physiochemical structure. Thermogravimetric analysis coupled with mass spectroscopy (TGA-MS) and Fourier transform infrared spectroscopy (TGA-FTIR) were employed to examine the biomass thermal degradation. TGA and DTG (Derivative thermogravimetry) indicated that the maximum degradation temperatures increased after Acid pretreatment due to the minerals catalytic effects. The main permanent evolved gases comprising H2, CO2, CO were detected online during analysis. The major permanent gases produced at the temperature range of 250–750 °C were attributed to the condensable vapors cracking and probably some secondary reactions. The physiochemical structure change of the Acid-treated biomass samples was examined by using Brunauer Emmett Teller (BET) method, Scanning Electron Microscope (SEM) and FTIR. The pyrolysis kinetics of the different palm oil biomasses were investigated using first order reaction model.
Denis Badocco - One of the best experts on this subject based on the ideXlab platform.
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formation of volatile iodine compounds under hot concentrated Acid conditions nitric Acid or aqua regia and in Diluted Acid solutions with or without thiocyanate
Polyhedron, 2017Co-Authors: Denis Badocco, Francesca Romanini, Valerio Di Marco, Andrea Mondin, Paolo PastoreAbstract:Abstract It is reported that iodine volatilization can occur in any elemental analysis of total iodine by ICP-MS. This problem affects the accuracy of the results, and it has been neither rationalized nor solved up to now. In this work, the formation of volatile iodine compounds in concentrated Acid solutions (nitric Acid or aqua regia) under microwave heating was studied by UV–Vis spectrophotometry, linear sweep voltammetry, and cyclic voltammetry. It was evidenced that molecular iodine (I2) can unexpectedly form in concentrated hot HNO3 solutions, irrespective of the starting iodine compound (iodide, iodate, periodate, 3-iodo- l -tyrosine, 3,5-diiodo- l -tyrosine dehydrate). I2 is produced by the nitrogen oxides existing in these conditions. The formation of volatile iodine is minimized in aqua regia, as chloride is able to keep iodine in solution due to the formation of charged chloro-iodo complexes (e.g. I2Cl−). The dilution of the concentrated Acid solution, required prior to the ICP-MS analysis, causes the disruption of I2Cl− so that I2 can again volatilize. To avoid this, 0.1 M thiocyanate can be added, as it forms a strong I2SCN− complex which keeps I2 in solution as ion. Also other iodine species possibly occurring in the explored conditions, iodide and iodate, were demonstrated to be converted to I2SCN− in Diluted HNO3 solutions and in the presence of 0.1 M thiocyanate. Recovery tests demonstrated that iodine volatilization is minimized if samples containing iodine are treated in aqua regia and, after dilution, they are added with 0.1 M thiocyanate.
Nei Pereira - One of the best experts on this subject based on the ideXlab platform.
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production of ethanol 3g from kappaphycus alvarezii evaluation of different process strategies
Bioresource Technology, 2013Co-Authors: Paulo I Hargreaves, Carolina Araujo Barcelos, Antonio Carlos Augusto Da Costa, Nei PereiraAbstract:Abstract This study evaluated the potential of Kappaphycus alvarezii as feedstock for ethanol production, i.e. ethanol 3G. First, aquatic biomass was subjected to a Diluted Acid pretreatment. This Acid pretreatment generated two streams – a galactose-containing liquid fraction and a cellulose-containing solid fraction, which were investigated to determine their fermentability with the following strategies: a single-stream process (simultaneous saccharification and co-fermentation (SSCF) of both fractions altogether), which achieved 64.3 g L−1 of ethanol, and a two-stream process (fractions were fermented separately), which resulted in 38 g L−1 of ethanol from the liquid fraction and 53.0 g L−1 from the simultaneous saccharification and fermentation (SSF) of the solid fraction. Based on the average fermentable carbohydrate concentration, it was possible to obtain 105 L of ethanol per ton of dry seaweed. These preliminaries results indicate that the use of the macro-algae K. alvarezii has a good potential feedstock for bioethanol production.
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ethanol production from residual wood chips of cellulose industry Acid pretreatment investigation hemicellulosic hydrolysate fermentation and remaining solid fraction fermentation by ssf process
Applied Biochemistry and Biotechnology, 2011Co-Authors: Neumara Luci Conceicao Silva, Gabriel Jaime Vargas Betancur, Mariana Penuela Vasquez, Edelvio De Barros Gomes, Nei PereiraAbstract:Current research indicates the ethanol fuel production from lignocellulosic materials, such as residual wood chips from the cellulose industry, as new emerging technology. This work aimed at evaluating the ethanol production from hemicellulose of eucalyptus chips by Diluted Acid pretreatment and the subsequent fermentation of the generated hydrolysate by a flocculating strain of Pichia stipitis. The remaining solid fraction generated after pretreatment was subjected to enzymatic hydrolysis, which was carried out simultaneously with glucose fermentation [saccharification and fermentation (SSF) process] using a strain of Saccharomyces cerevisiae. The Acid pretreatment was evaluated using a central composite design for sulfuric Acid concentration (1.0–4.0 v/v) and solid to liquid ratio (1:2–1:4, grams to milliliter) as independent variables. A maximum xylose concentration of 50 g/L was obtained in the hemicellulosic hydrolysate. The fermentation of hemicellulosic hydrolysate and the SSF process were performed in bioreactors and the final ethanol concentrations of 15.3 g/L and 28.7 g/L were obtained, respectively.
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Sugar cane bagasse as feedstock for second generation ethanol production. Part II: Hemicellulose hydrolysate fermentability
Electronic Journal of Biotechnology, 2010Co-Authors: Gabriel Jaime Vargas Betancur, Nei PereiraAbstract:Sugar cane bagasse is produced in Brazil as waste of the sugar and ethanol industries. This lignocellulosic material is a potential source for second-generation ethanol production; however a pretreatment stage is essential, which aims at removing the hemicellulose component by disorganizing the lignocellulosic complex. In this work sugar cane bagasse was pretreated by Diluted Acid hydrolysis resulting in xylose-rich hydrolysates, which could be fermented to ethanol by a strain of the yeast Pichia stipitis . Statistical approach was used to investigate the effects of factors associated with the Diluted Acid hydrolysis process (Acid concentration, solid:liquid ratio and time of exposure) on the fermentability of different hydrolysates. The statistical analysis was useful for determining the effects of the individual factors and their interactions on the response variables. An Acid concentration of 1.09% (v/v), a solid:liquid ratio of 1:2.8 (g:ml), and an exposure time of 27 min were established and validated as the optimum pretreatment conditions for ethanol production from hemicellulose hydrolysates of sugar cane bagasse. Under these conditions, a hydrolysate with 50 g/l of xylose, 6.04 g/l of acetic Acid, 0.55 g/l of hydroxylmethylfurfural and 0.09 g/l of furfural was obtained and its fermentation yielded roughly 20 g/l of ethanol in 40 hrs.
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sugar cane bagasse as feedstock for second generation ethanol production part i Diluted Acid pretreatment optimization
Electronic Journal of Biotechnology, 2010Co-Authors: Gabriel Jaime Vargas Betancur, Nei PereiraAbstract:Tons of sugar cane bagasse are produced in Brazil as waste of the sugar and ethanol industries. This lignocellulosic material is a potential source for second-generation ethanol production. Diluted Acid hydrolysis is one of the most efficient pretreatments for hemicellulosic solubilization. The hydrolysate obtained is rich in xylose, which can be converted to ethanol by Pichia stipitis. This work used a statistical approach and the severity factor to investigate the effects of factors associated with the Diluted Acid hydrolysis process (Acid concentration, solid:liquid ratio and time of exposure) on various response variables (xylose concentration, hydrolysis yield, inhibitor concentration and hydrolysate fermentability). The severity factor had a strong influence on the generation of inhibitors. The statistical analysis was useful for determining the effects of the individual factors and their interactions on the response variables. An Acid concentration of 1.09% (vv), an S:L ratio of 1:2.8 (g:ml), and an exposure time of 27 min were established and validated as the optimum pretreatment conditions for the generation of hydrolysates with high xylose concentration and low contents of inhibitors. In such conditions, hydrolysate with 50 g/l of xylose was obtained.