The Experts below are selected from a list of 11994 Experts worldwide ranked by ideXlab platform
Eulogio Castro - One of the best experts on this subject based on the ideXlab platform.
-
Application of a combined fungal and diluted acid pretreatment on Olive Tree biomass
Industrial Crops and Products, 2018Co-Authors: José Carlos Martínez-patiño, Inmaculada Romero, Eulogio Castro, Encarnacion Ruiz, Thelmo A. Lu-chau, Beatriz Gullón, Juan M. LemaAbstract:Abstract A biological pretreatment of Olive Tree biomass (OTB) was carried out. First, seven white-rot fungi (WRF) were screened on solid-state fermentations by analyzing the substrate composition, ligninolytic enzymes production and enzymatic hydrolysis yields at three different pretreatment times (15, 30 and 45 days). Glucose released by enzymatic hydrolysis of OTB pretreated with Irpex lacteus for 45 days doubled that obtained with the control (non-inoculated). In addition, to enhance this yield, the combination of fungal pretreatment with a chemical pretreatment was studied. It was also found that the order of the pretreatment combination has a relevant effect on the glucose yield. Thereby, the best option determined, fungal pretreatment with I. lacteus after 28 days of culture followed by diluted acid pretreatment (2% w/v H2SO4, 130 °C and 90 min), enhanced 34% the enzymatic hydrolysis yield compared with the acid pretreatment alone. Applying the best pretreatment combination, the overall sugar yield of the whole process (sequential pretreatment plus enzymatic hydrolysis) was 51% of the theoretical yield.
-
assessing cellulose nanofiber production from Olive Tree pruning residue
Carbohydrate Polymers, 2018Co-Authors: Úrsula Fillat, Eulogio Castro, David Ibarra, Raquel Martinsampedro, Bernd Wicklein, Eduardo Ruizhitzky, C Valencia, Andres Sarrion, María E. EugenioAbstract:Abstract Pruning operation in Olive Trees generates a large amount of biomass that is normally burned causing severe environmental concern. Therefore, the transformation of this agricultural residue into value-added products is imperative but still remains as a technological challenge. In this study, Olive Tree pruning (OTP) residue is evaluated for the first time to produce cellulose nanofibers (CNF). The OTP bleached pulp was treated by TEMPO-mediated oxidation and subsequent defibrillation in a microfluidizer. The resulting CNF was characterized and compared to CNF obtained from a commercial bleached eucalyptus kraft pulp using the same chemi-mechanical procedure. CNF from OTP showed higher carboxylate content but lower fibrillation yield and optical transmittance as compared to eucalyptus CNF. Finally, the visco-elastic gel obtained from OTP was stronger than that produced from eucalyptus. Therefore, the properties of CNF from OTP made this nanomaterial suitable for several applications. CNF from OTP showed higher carboxylate content as compared to eucalyptus CNF (1038 vs . 778 μmol/g) but lower fibrillation yield (48% vs . 96%) and optical transmittance. Finally, the visco-elastic gel obtained from OTP was stronger than that produced from eucalyptus. Therefore, the properties of CNF from OTP made this nanomaterial suitable for several applications.
-
residual biomass potential in Olive Tree cultivation and Olive oil industry in spain valorization proposal in a biorefinery context
Spanish Journal of Agricultural Research, 2017Co-Authors: Paloma Manzanares, Encarnacion Ruiz, María José Negro, Mercedes Ballesteros, F J Gallego, Juan Carlos Lopezlinares, Eulogio CastroAbstract:Olive crop and Olive oil industry generates several residues, i.e ., Olive Tree pruning biomass (OTPB), extracted Olive pomace (EOP) and Olive leaves (OL) that could be used to produce high-added value products in an integrated biorefinery. OTPB is generated in the field as a result of pruning operation to remove old branches; EOP is the main residue of the pomace Olive oil extracting industry after extraction with hexane of residual oil contained in Olive pomace; and OL comes from the Olive cleaning process carried out at Olive mills, where small branches and leaves are separated by density. In this work, an analysis of the potential of OTPB, EOP and OL residues was addressed by estimating the production volumes at national level and the spatial distribution of these residues using geographic information system software. Information provided by public institutions and personal surveys to the industries was evaluated. Moreover, chemical analysis of the residues was undertaken and the results used to make a first assessment of valorization into biofuels such as bioethanol and bio based chemicals. Results show that close to 4.2 million tons/year of EOP, OL and OTPB derived from Olive oil industry and Olive Tree cultivation in Spain could be available as a raw material for biorefineries in Spain. The analysis of the chemical characteristics indicates the relevant potential of these feedstocks for the production of bioethanol and other compounds such as phenols based on suitable processing and conversion routes, although techno-economic evaluations must be tackled to refine this approach.
-
combined acid alkaline peroxide pretreatment of Olive Tree biomass for bioethanol production
Bioresource Technology, 2017Co-Authors: Jose Carlos Martinezpatino, Cristóbal Cara, Inmaculada Romero, Encarnacion Ruiz, Juan Carlos Lopezlinares, Eulogio CastroAbstract:Olive Tree biomass (OTB) can be used for producing second generation bioethanol. In this work, extracted OTB was subjected to fractionation using a sequential acid/alkaline oxidative pretreatment. In the first acid stage, the effects of sulfuric acid concentration and reaction times at 130°C were investigated. Up to 71% solubilization of hemicellulosic sugars was achieved under optimized conditions (2.4% H2SO4, 84min). In the second stage, the influence of hydrogen peroxide concentration and process time were evaluated at 80°C. Approximately 80% delignification was achieved under the best operational conditions (7% H2O2, 90min) within the experimental range studied. This pretreatment produced a substrate with 72% cellulose that was highly accessible to enzymatic attack, yielding 82g glucose/100g glucose in delignified OTB. Ethanol production from both hemicellulosic sugars solubilized in the acid pretreatment and glucose from enzymatic hydrolysis of delignified OTB yielded 15g ethanol/100g OTB.
-
design and optimization of sulfuric acid pretreatment of extracted Olive Tree biomass using response surface methodology
Bioresources, 2017Co-Authors: Jose Carlos Martinezpatino, Cristóbal Cara, Inmaculada Romero, Encarnacion Ruiz, Juan Miguel Romerogarcia, Eulogio CastroAbstract:Olive Tree biomass (OTB) represents an interesting feedstock for bioethanol production. In this study, Olive Tree pruning was water extracted and pretreated by dilute sulfuric acid to achieve high sugar recoveries from cellulosic and hemicellulosic fractions. Temperature (160 to 200 °C), acid concentration (0 to 8 g acid/100 g extracted raw material), and solids loading (15% to 35% w/v) were selected as operation variables and modified according to a Box-Behnken experimental design. The optimal conditions for the acid pretreatment were 160 °C, 4.9 g sulfuric acid/100 g biomass, and 35% solids loading (w/v), according to multiple criteria that considered the maximization of both the hemicellulosic sugars concentration in prehydrolysate and the overall sugar yield. These optimized conditions yielded a sugar concentration of 79.8 g/L, corresponding to an overall yield of 39.8 g total sugars/100 g extracted OTB. The fermentability of hemicellulosic sugars prehydrolysates from the acid pretreatment was evaluated by Escherichia coli after a detoxification stage by overliming. The prehydrolysates with lower concentrations of toxic compounds were fermented and achieved ethanol yields higher than 80% of the theoretical ethanol yield.
Encarnacion Ruiz - One of the best experts on this subject based on the ideXlab platform.
-
Application of a combined fungal and diluted acid pretreatment on Olive Tree biomass
Industrial Crops and Products, 2018Co-Authors: José Carlos Martínez-patiño, Inmaculada Romero, Eulogio Castro, Encarnacion Ruiz, Thelmo A. Lu-chau, Beatriz Gullón, Juan M. LemaAbstract:Abstract A biological pretreatment of Olive Tree biomass (OTB) was carried out. First, seven white-rot fungi (WRF) were screened on solid-state fermentations by analyzing the substrate composition, ligninolytic enzymes production and enzymatic hydrolysis yields at three different pretreatment times (15, 30 and 45 days). Glucose released by enzymatic hydrolysis of OTB pretreated with Irpex lacteus for 45 days doubled that obtained with the control (non-inoculated). In addition, to enhance this yield, the combination of fungal pretreatment with a chemical pretreatment was studied. It was also found that the order of the pretreatment combination has a relevant effect on the glucose yield. Thereby, the best option determined, fungal pretreatment with I. lacteus after 28 days of culture followed by diluted acid pretreatment (2% w/v H2SO4, 130 °C and 90 min), enhanced 34% the enzymatic hydrolysis yield compared with the acid pretreatment alone. Applying the best pretreatment combination, the overall sugar yield of the whole process (sequential pretreatment plus enzymatic hydrolysis) was 51% of the theoretical yield.
-
residual biomass potential in Olive Tree cultivation and Olive oil industry in spain valorization proposal in a biorefinery context
Spanish Journal of Agricultural Research, 2017Co-Authors: Paloma Manzanares, Encarnacion Ruiz, María José Negro, Mercedes Ballesteros, F J Gallego, Juan Carlos Lopezlinares, Eulogio CastroAbstract:Olive crop and Olive oil industry generates several residues, i.e ., Olive Tree pruning biomass (OTPB), extracted Olive pomace (EOP) and Olive leaves (OL) that could be used to produce high-added value products in an integrated biorefinery. OTPB is generated in the field as a result of pruning operation to remove old branches; EOP is the main residue of the pomace Olive oil extracting industry after extraction with hexane of residual oil contained in Olive pomace; and OL comes from the Olive cleaning process carried out at Olive mills, where small branches and leaves are separated by density. In this work, an analysis of the potential of OTPB, EOP and OL residues was addressed by estimating the production volumes at national level and the spatial distribution of these residues using geographic information system software. Information provided by public institutions and personal surveys to the industries was evaluated. Moreover, chemical analysis of the residues was undertaken and the results used to make a first assessment of valorization into biofuels such as bioethanol and bio based chemicals. Results show that close to 4.2 million tons/year of EOP, OL and OTPB derived from Olive oil industry and Olive Tree cultivation in Spain could be available as a raw material for biorefineries in Spain. The analysis of the chemical characteristics indicates the relevant potential of these feedstocks for the production of bioethanol and other compounds such as phenols based on suitable processing and conversion routes, although techno-economic evaluations must be tackled to refine this approach.
-
combined acid alkaline peroxide pretreatment of Olive Tree biomass for bioethanol production
Bioresource Technology, 2017Co-Authors: Jose Carlos Martinezpatino, Cristóbal Cara, Inmaculada Romero, Encarnacion Ruiz, Juan Carlos Lopezlinares, Eulogio CastroAbstract:Olive Tree biomass (OTB) can be used for producing second generation bioethanol. In this work, extracted OTB was subjected to fractionation using a sequential acid/alkaline oxidative pretreatment. In the first acid stage, the effects of sulfuric acid concentration and reaction times at 130°C were investigated. Up to 71% solubilization of hemicellulosic sugars was achieved under optimized conditions (2.4% H2SO4, 84min). In the second stage, the influence of hydrogen peroxide concentration and process time were evaluated at 80°C. Approximately 80% delignification was achieved under the best operational conditions (7% H2O2, 90min) within the experimental range studied. This pretreatment produced a substrate with 72% cellulose that was highly accessible to enzymatic attack, yielding 82g glucose/100g glucose in delignified OTB. Ethanol production from both hemicellulosic sugars solubilized in the acid pretreatment and glucose from enzymatic hydrolysis of delignified OTB yielded 15g ethanol/100g OTB.
-
design and optimization of sulfuric acid pretreatment of extracted Olive Tree biomass using response surface methodology
Bioresources, 2017Co-Authors: Jose Carlos Martinezpatino, Cristóbal Cara, Inmaculada Romero, Encarnacion Ruiz, Juan Miguel Romerogarcia, Eulogio CastroAbstract:Olive Tree biomass (OTB) represents an interesting feedstock for bioethanol production. In this study, Olive Tree pruning was water extracted and pretreated by dilute sulfuric acid to achieve high sugar recoveries from cellulosic and hemicellulosic fractions. Temperature (160 to 200 °C), acid concentration (0 to 8 g acid/100 g extracted raw material), and solids loading (15% to 35% w/v) were selected as operation variables and modified according to a Box-Behnken experimental design. The optimal conditions for the acid pretreatment were 160 °C, 4.9 g sulfuric acid/100 g biomass, and 35% solids loading (w/v), according to multiple criteria that considered the maximization of both the hemicellulosic sugars concentration in prehydrolysate and the overall sugar yield. These optimized conditions yielded a sugar concentration of 79.8 g/L, corresponding to an overall yield of 39.8 g total sugars/100 g extracted OTB. The fermentability of hemicellulosic sugars prehydrolysates from the acid pretreatment was evaluated by Escherichia coli after a detoxification stage by overliming. The prehydrolysates with lower concentrations of toxic compounds were fermented and achieved ethanol yields higher than 80% of the theoretical ethanol yield.
-
high solids loading pretreatment of Olive Tree pruning with dilute phosphoric acid for bioethanol production by escherichia coli
Energy & Fuels, 2015Co-Authors: Jose Carlos Martinezpatino, Inmaculada Romero, Encarnacion Ruiz, J M Oliva, María José Negro, Juan Miguel Romerogarcia, Cristina Alvarez, Eulogio CastroAbstract:This paper deals with a new approach for using Olive Tree pruning biomass as raw material for ethanol and other chemical production. This process includes a water extraction step, followed by a high solids loading dilute phosphoric acid pretreatment and an ethanologenic Escherichia coli fermentation for the conversion of all of the sugars released. Results show that the operational conditions leading to the maximal hemicelullosic sugar recovery in the liquid fraction (near 70%) are 170 °C and 0.5% (w/v) phosphoric acid concentration. The fermentation of the mixed sugars found in the detoxified prehydrolysates by ethanologenic E. coli MS04 led to an ethanol concentration of 23 g/L and an ethanol yield of 0.46 g of ethanol/g of sugars consumed. When the ethanol production from the pretreated solids after enzymatic hydrolysis is also taken into account, 13.2 g of ethanol/100 g of original material was obtained. The production of other interesting compounds is also considered.
Cristóbal Cara - One of the best experts on this subject based on the ideXlab platform.
-
combined acid alkaline peroxide pretreatment of Olive Tree biomass for bioethanol production
Bioresource Technology, 2017Co-Authors: Jose Carlos Martinezpatino, Cristóbal Cara, Inmaculada Romero, Encarnacion Ruiz, Juan Carlos Lopezlinares, Eulogio CastroAbstract:Olive Tree biomass (OTB) can be used for producing second generation bioethanol. In this work, extracted OTB was subjected to fractionation using a sequential acid/alkaline oxidative pretreatment. In the first acid stage, the effects of sulfuric acid concentration and reaction times at 130°C were investigated. Up to 71% solubilization of hemicellulosic sugars was achieved under optimized conditions (2.4% H2SO4, 84min). In the second stage, the influence of hydrogen peroxide concentration and process time were evaluated at 80°C. Approximately 80% delignification was achieved under the best operational conditions (7% H2O2, 90min) within the experimental range studied. This pretreatment produced a substrate with 72% cellulose that was highly accessible to enzymatic attack, yielding 82g glucose/100g glucose in delignified OTB. Ethanol production from both hemicellulosic sugars solubilized in the acid pretreatment and glucose from enzymatic hydrolysis of delignified OTB yielded 15g ethanol/100g OTB.
-
design and optimization of sulfuric acid pretreatment of extracted Olive Tree biomass using response surface methodology
Bioresources, 2017Co-Authors: Jose Carlos Martinezpatino, Cristóbal Cara, Inmaculada Romero, Encarnacion Ruiz, Juan Miguel Romerogarcia, Eulogio CastroAbstract:Olive Tree biomass (OTB) represents an interesting feedstock for bioethanol production. In this study, Olive Tree pruning was water extracted and pretreated by dilute sulfuric acid to achieve high sugar recoveries from cellulosic and hemicellulosic fractions. Temperature (160 to 200 °C), acid concentration (0 to 8 g acid/100 g extracted raw material), and solids loading (15% to 35% w/v) were selected as operation variables and modified according to a Box-Behnken experimental design. The optimal conditions for the acid pretreatment were 160 °C, 4.9 g sulfuric acid/100 g biomass, and 35% solids loading (w/v), according to multiple criteria that considered the maximization of both the hemicellulosic sugars concentration in prehydrolysate and the overall sugar yield. These optimized conditions yielded a sugar concentration of 79.8 g/L, corresponding to an overall yield of 39.8 g total sugars/100 g extracted OTB. The fermentability of hemicellulosic sugars prehydrolysates from the acid pretreatment was evaluated by Escherichia coli after a detoxification stage by overliming. The prehydrolysates with lower concentrations of toxic compounds were fermented and achieved ethanol yields higher than 80% of the theoretical ethanol yield.
-
pretreatment of Olive Tree biomass with fecl3 prior enzymatic hydrolysis
Bioresource Technology, 2013Co-Authors: Juan Carlos Lopezlinares, Cristóbal Cara, Inmaculada Romero, Manuel Moya, Encarnacion Ruiz, Eulogio CastroAbstract:Abstract Olive Tree biomass (OTB) is an agricultural residue which can be used as raw material for bioethanol production. OTB was pretreated with 0.05–0.275 M FeCl 3 solutions at 120–180 °C for 0–30 min. Enzymatic hydrolysis yields were used for assessing pretreatment performance. Optimum FeCl 3 pretreatment conditions were found to be 152.6 °C, 0.26 M FeCl 3 for 30 min. Under such conditions, 100% of hemicellulose was removed, and enzymatic hydrolysis of pretreated solids resulted in a yield of 36.6 g glucose/100 g of glucose in the raw material. Hemicellulosic sugar recovery in the prehydrolysate was 63.2%. Results compare well with those obtained by other pretreatment strategies on the same raw material, confirming FeCl 3 solutions as a new, feasible approach for bioethanol production.
-
production purification and characterisation of oligosaccharides from Olive Tree pruning autohydrolysis
Industrial Crops and Products, 2012Co-Authors: Cristóbal Cara, Florbela Carvalheiro, Eulogio Castro, Ignacio Ballesteros, Encarnacion Ruiz, Patricia Moura, Francisco M GirioAbstract:Abstract The production of oligosaccharides (OS) by Olive Tree pruning autohydrolysis in the range 170–230 °C was studied. The best results in terms of maximum yield of OS along with a low amount of byproducts were obtained at 180 °C. After purification by preparative gel filtration chromatography a range of OS-fractions with average degree of polymerisation (DP) from 25 to 3 was selected for further characterisation. Gluco- and xylooligosaccharides were the predominant OS in these fractions. OS yields in the range 80–90% were obtained for fractions with average DP between 25 and 7, practically free of low molecular compounds. Both OS total yields and xylooligosaccharides proportion decreased for lower DP fractions while monosaccharides and other products concentrations increased. OS production and the recovery of other high value compounds can be envisaged as an interesting contribution to develop an Olive-biomass biorefinery.
-
effect of water extraction on sugars recovery from steam exploded Olive Tree pruning
Bioresource Technology, 2011Co-Authors: Ignacio Ballesteros, Cristóbal Cara, Felicia Sáez, Eulogio Castro, María José Negro, Mercedes Ballesteros, Paloma Manzanares, J M OlivaAbstract:Biomass of Olive Tree pruning can be considered a suitable raw material for the production of ethanol due to its high content of potentially fermentable carbohydrates. However its high extractives content could cause condensation reactions between extractives and acid insoluble lignin during pretreatment, hindering the enzymatic hydrolysis of pretreated material. In this work, the effect of extractives removal before steam explosion of Olive Tree pruning was evaluated. The objectives are to recover as much glucose as possible in the extraction stage and to avoid the condensation reactions. The effect of temperature and time of water extracted material on sugars recovery was studied using a response surface method according to a central composite design. Extractive removal previous to steam explosion resulted in 20% more total sugars recovery in comparison to a material without water extraction stage.
Inmaculada Romero - One of the best experts on this subject based on the ideXlab platform.
-
Application of a combined fungal and diluted acid pretreatment on Olive Tree biomass
Industrial Crops and Products, 2018Co-Authors: José Carlos Martínez-patiño, Inmaculada Romero, Eulogio Castro, Encarnacion Ruiz, Thelmo A. Lu-chau, Beatriz Gullón, Juan M. LemaAbstract:Abstract A biological pretreatment of Olive Tree biomass (OTB) was carried out. First, seven white-rot fungi (WRF) were screened on solid-state fermentations by analyzing the substrate composition, ligninolytic enzymes production and enzymatic hydrolysis yields at three different pretreatment times (15, 30 and 45 days). Glucose released by enzymatic hydrolysis of OTB pretreated with Irpex lacteus for 45 days doubled that obtained with the control (non-inoculated). In addition, to enhance this yield, the combination of fungal pretreatment with a chemical pretreatment was studied. It was also found that the order of the pretreatment combination has a relevant effect on the glucose yield. Thereby, the best option determined, fungal pretreatment with I. lacteus after 28 days of culture followed by diluted acid pretreatment (2% w/v H2SO4, 130 °C and 90 min), enhanced 34% the enzymatic hydrolysis yield compared with the acid pretreatment alone. Applying the best pretreatment combination, the overall sugar yield of the whole process (sequential pretreatment plus enzymatic hydrolysis) was 51% of the theoretical yield.
-
combined acid alkaline peroxide pretreatment of Olive Tree biomass for bioethanol production
Bioresource Technology, 2017Co-Authors: Jose Carlos Martinezpatino, Cristóbal Cara, Inmaculada Romero, Encarnacion Ruiz, Juan Carlos Lopezlinares, Eulogio CastroAbstract:Olive Tree biomass (OTB) can be used for producing second generation bioethanol. In this work, extracted OTB was subjected to fractionation using a sequential acid/alkaline oxidative pretreatment. In the first acid stage, the effects of sulfuric acid concentration and reaction times at 130°C were investigated. Up to 71% solubilization of hemicellulosic sugars was achieved under optimized conditions (2.4% H2SO4, 84min). In the second stage, the influence of hydrogen peroxide concentration and process time were evaluated at 80°C. Approximately 80% delignification was achieved under the best operational conditions (7% H2O2, 90min) within the experimental range studied. This pretreatment produced a substrate with 72% cellulose that was highly accessible to enzymatic attack, yielding 82g glucose/100g glucose in delignified OTB. Ethanol production from both hemicellulosic sugars solubilized in the acid pretreatment and glucose from enzymatic hydrolysis of delignified OTB yielded 15g ethanol/100g OTB.
-
design and optimization of sulfuric acid pretreatment of extracted Olive Tree biomass using response surface methodology
Bioresources, 2017Co-Authors: Jose Carlos Martinezpatino, Cristóbal Cara, Inmaculada Romero, Encarnacion Ruiz, Juan Miguel Romerogarcia, Eulogio CastroAbstract:Olive Tree biomass (OTB) represents an interesting feedstock for bioethanol production. In this study, Olive Tree pruning was water extracted and pretreated by dilute sulfuric acid to achieve high sugar recoveries from cellulosic and hemicellulosic fractions. Temperature (160 to 200 °C), acid concentration (0 to 8 g acid/100 g extracted raw material), and solids loading (15% to 35% w/v) were selected as operation variables and modified according to a Box-Behnken experimental design. The optimal conditions for the acid pretreatment were 160 °C, 4.9 g sulfuric acid/100 g biomass, and 35% solids loading (w/v), according to multiple criteria that considered the maximization of both the hemicellulosic sugars concentration in prehydrolysate and the overall sugar yield. These optimized conditions yielded a sugar concentration of 79.8 g/L, corresponding to an overall yield of 39.8 g total sugars/100 g extracted OTB. The fermentability of hemicellulosic sugars prehydrolysates from the acid pretreatment was evaluated by Escherichia coli after a detoxification stage by overliming. The prehydrolysates with lower concentrations of toxic compounds were fermented and achieved ethanol yields higher than 80% of the theoretical ethanol yield.
-
high solids loading pretreatment of Olive Tree pruning with dilute phosphoric acid for bioethanol production by escherichia coli
Energy & Fuels, 2015Co-Authors: Jose Carlos Martinezpatino, Inmaculada Romero, Encarnacion Ruiz, J M Oliva, María José Negro, Juan Miguel Romerogarcia, Cristina Alvarez, Eulogio CastroAbstract:This paper deals with a new approach for using Olive Tree pruning biomass as raw material for ethanol and other chemical production. This process includes a water extraction step, followed by a high solids loading dilute phosphoric acid pretreatment and an ethanologenic Escherichia coli fermentation for the conversion of all of the sugars released. Results show that the operational conditions leading to the maximal hemicelullosic sugar recovery in the liquid fraction (near 70%) are 170 °C and 0.5% (w/v) phosphoric acid concentration. The fermentation of the mixed sugars found in the detoxified prehydrolysates by ethanologenic E. coli MS04 led to an ethanol concentration of 23 g/L and an ethanol yield of 0.46 g of ethanol/g of sugars consumed. When the ethanol production from the pretreated solids after enzymatic hydrolysis is also taken into account, 13.2 g of ethanol/100 g of original material was obtained. The production of other interesting compounds is also considered.
-
Ethanol production from glucose and xylose obtained from steam exploded water-extracted Olive Tree pruning using phosphoric acid as catalyst.
Bioresource technology, 2013Co-Authors: María José Negro, Inmaculada Romero, Eulogio Castro, Manuel Moya, Ignacio Ballesteros, C. Álvarez, Mercedes Ballesteros, Paloma Manzanares, José Miguel OlivaAbstract:Abstract In this work, the effect of phosphoric acid (1% w/w) in steam explosion pretreatment of water extracted Olive Tree pruning at 175 °C and 195 °C was evaluated. The objective is to produce ethanol from all sugars (mainly glucose and xylose) contained in the pretreated material. The water insoluble fraction obtained after pretreatment was used as substrate in a simultaneous saccharification and fermentation (SSF) process by a commercial strain of Saccharomyces cerevisiae. The liquid fraction, containing mainly xylose, was detoxified by alkali and ion-exchange resin and then fermented by the xylose fermenting yeast Scheffersomyces stipitis. Ethanol yields reached in a SSF process were close to 80% when using 15% (w/w) substrate consistency and about 70% of theoretical when using prehydrolysates detoxified by ion-exchange resins. Considering sugars recovery and ethanol yields about 160 g of ethanol from kg of water extracted Olive Tree pruning could be obtained.
Manuel Moya - One of the best experts on this subject based on the ideXlab platform.
-
Ethanol production from glucose and xylose obtained from steam exploded water-extracted Olive Tree pruning using phosphoric acid as catalyst.
Bioresource technology, 2013Co-Authors: María José Negro, Inmaculada Romero, Eulogio Castro, Manuel Moya, Ignacio Ballesteros, C. Álvarez, Mercedes Ballesteros, Paloma Manzanares, José Miguel OlivaAbstract:Abstract In this work, the effect of phosphoric acid (1% w/w) in steam explosion pretreatment of water extracted Olive Tree pruning at 175 °C and 195 °C was evaluated. The objective is to produce ethanol from all sugars (mainly glucose and xylose) contained in the pretreated material. The water insoluble fraction obtained after pretreatment was used as substrate in a simultaneous saccharification and fermentation (SSF) process by a commercial strain of Saccharomyces cerevisiae. The liquid fraction, containing mainly xylose, was detoxified by alkali and ion-exchange resin and then fermented by the xylose fermenting yeast Scheffersomyces stipitis. Ethanol yields reached in a SSF process were close to 80% when using 15% (w/w) substrate consistency and about 70% of theoretical when using prehydrolysates detoxified by ion-exchange resins. Considering sugars recovery and ethanol yields about 160 g of ethanol from kg of water extracted Olive Tree pruning could be obtained.
-
pretreatment of Olive Tree biomass with fecl3 prior enzymatic hydrolysis
Bioresource Technology, 2013Co-Authors: Juan Carlos Lopezlinares, Cristóbal Cara, Inmaculada Romero, Manuel Moya, Encarnacion Ruiz, Eulogio CastroAbstract:Abstract Olive Tree biomass (OTB) is an agricultural residue which can be used as raw material for bioethanol production. OTB was pretreated with 0.05–0.275 M FeCl 3 solutions at 120–180 °C for 0–30 min. Enzymatic hydrolysis yields were used for assessing pretreatment performance. Optimum FeCl 3 pretreatment conditions were found to be 152.6 °C, 0.26 M FeCl 3 for 30 min. Under such conditions, 100% of hemicellulose was removed, and enzymatic hydrolysis of pretreated solids resulted in a yield of 36.6 g glucose/100 g of glucose in the raw material. Hemicellulosic sugar recovery in the prehydrolysate was 63.2%. Results compare well with those obtained by other pretreatment strategies on the same raw material, confirming FeCl 3 solutions as a new, feasible approach for bioethanol production.
-
acid hydrolysis of Olive Tree biomass
Chemical Engineering Research & Design, 2010Co-Authors: Inmaculada Romero, Eulogio Castro, Encarnacion Ruiz, Manuel MoyaAbstract:Abstract Olive Tree cultivation generates a great amount of biomass residues which have no industrial application. Pruning residues are usually grindered or burnt on fields, causing economical costs and environmental concerns. An alternative issue for these renewable sugar-containing feedstocks may be the conversion into fuel ethanol by hydrolysis and fermentation. As a first step in the bioconversion process, the acid hydrolysis of Olive Tree pruning is studied and a mathematical model predicting both fiber content and sugar release as a function of operation variables is proposed. Sulphuric acid concentration in the range 0–32% (w/w), process temperature between 60 and 90 °C and hydrolysis time from 0 to 240 min were used as hydrolysis conditions. The process was modelled by first-order reaction kinetics. The apparent kinetic constant relating acid concentration to fiber hydrolysis and sugar release shows a potential dependence; on the other hand, an Arrhenius-type equation has enabled the evaluation of activation energy values of 26.4 and 25.9 kJ/mol for fiber hydrolysis and sugar generation, respectively.
-
inhibition of pichia stipitis fermentation of hydrolysates from Olive Tree cuttings
World Journal of Microbiology & Biotechnology, 2009Co-Authors: M A Diaz, Cristóbal Cara, Inmaculada Romero, Manuel Moya, Encarnacion Ruiz, Eulogio CastroAbstract:The ethanolic fermentation of liquid fractions (hydrolysates) issued from dilute acid pre-treatment of Olive Tree biomass by Pichia stipitis is reported for the first time. On the one side, P. stipitis has been reported as the most promising naturally occurring C5 fermenting microorganism; on the other side, Olive Tree biomass is a renewable, low cost, and lacking of alternatives agricultural residue especially abundant in Mediterranean countries. The study was performed in two steps. First, the fermentation performance of P. stipitis was evaluated on a fermentation medium also containing the main inhibitors found in these hydrolysates (acetic acid, formic acid, and furfural), as well as glucose and xylose as carbon sources. The effect of inhibitors, individually or in a mixture, on kinetic and yield parameters was calculated. In a second step, hydrolysates obtained from 1% (w/w) sulfuric acid pre-treatment of Olive Tree biomass at 190°C for 10 min were used as a real fermentation medium with the same microorganism. Due to inhibition, effective fermentation required dilution of the hydrolysate and either overliming or activated charcoal treatment. Results show that ethanol yields obtained from hydrolysates, ranging from 0.35 to 0.42 g/g, are similar to those from synthetic medium, although the process proceeds at lower rates. Inhibiting compounds affect the fermentation performance in a synergistic way. Furfural is rapidly assimilated by the yeast; acetic acid and formic acid concentrations decrease slowly during the process. Activated charcoal or overliming detoxification improve the fermentability of diluted hydrolysates.
-
fermentation of Olive Tree pruning acid hydrolysates by pachysolen tannophilus
Biochemical Engineering Journal, 2007Co-Authors: Inmaculada Romero, Sebastian Sanchez, Eulogio Castro, Manuel Moya, Encarnacion Ruiz, Vicente BravoAbstract:Abstract The influence of hydrolysis conditions on the fermentation of hydrolysates obtained from Olive Tree pruning (a renewable, low cost, largely available agricultural residue) is analyzed in this work. Hydrolysis was performed using sulfuric acid at atmospheric pressure (90 °C) in a concentration range of 0.5–4N for 240 min. The fermentation of hydrolysates was carried out by Pachysolen tannophilus in a discontinuous tank bioreactor at 30 °C and pH 3.5. The main fermentation parameters determined in this study include maximum specific growth rate, biomass productivity, specific substrate consumption rate, specific ethanol production rate, and ethanol and xylitol yields. The results show that ethanol yields are much higher than xylitol yields under all the conditions tested. The maximum ethanol yield (0.38 g/g) is reached with the hydrolysate obtained with 0.75N sulfuric acid. Under these conditions the conversion of the hemicellulose fraction is 92%.
