The Experts below are selected from a list of 48789 Experts worldwide ranked by ideXlab platform
J A Labrincha - One of the best experts on this subject based on the ideXlab platform.
-
innovative recycling of lime slaker grits from Paper Pulp industry reused as aggregate in ambient cured biomass fly ash based geopolymers for sustainable construction material
Sustainability, 2019Co-Authors: Manfredi Saeli, L Senff, D M Tobaldi, Giada La Scalia, M P Seabra, J A LabrinchaAbstract:Lime slaker grits and biomass fly ash are solid wastes produced by the Kraft Paper-Pulp industry that are commonly disposed of in landfill. However, recent studies and European regulations discourage such disposal practices. This work investigates an alternative and innovative way to recycle and reuse these wastes in the production of green geopolymeric mortars intended for application in the construction industry. Here, biomass fly ash was used as the main source of alumino-silicate in the binder precursor (70 wt.% substitution to metakaolin), and grits (ranging from 1–12.5 mm, as provided by the industry) were reused as aggregate. Aggregate granulometry was also completed by using a commercial natural siliceous sand (<1 mm). Mortars using sand only were prepared for comparative reasons. The implemented mix was designed to investigate the influence of the grits on the mortar’s properties such as its binder/aggregate ratio, workability, bulk density, water sorptivity, and compressive strength. At the same time, waste reuse was analysed in light of its limitations and potentialities. Moreover, in the pursuit of sustainability, the manufacturing process that was followed was highly cost-effective in ambient curing conditions (20 °C, 65% RH), which avoided the use of any external source of energy as commonly used in geopolymers processing. The achieved results proved that the combined use of these wastes, which to date has hardly been explored, along with ambient manufacturing conditions increases the material sustainability. The produced mortars are suitable for innovative applications in various fields, with a particular focus on construction and contribute to the circular economy.
-
mix design and mechanical performance of geopolymeric binders and mortars using biomass fly ash and alkaline effluent from Paper Pulp industry
Journal of Cleaner Production, 2019Co-Authors: Manfredi Saeli, D M Tobaldi, M P Seabra, J A LabrinchaAbstract:Abstract This work investigates the use of biomass fly ash (BFA) and an alkaline effluent (AEF), both generated from the Kraft Pulp industry, in the preparation of geopolymeric binders and mortars for construction applications. BFA replaced the metakaolin (MK) while the AEF substituted the distilled water used to dissolve NaOH pellets. The mix design aims to maximize the amount of both the wastes and to optimize the materials properties, such as workability and mechanical performance. At the same time, also the environmental impact decreases enhancing the materials' sustainability and facilitating the circular economy. For the previously optimized BFA/MK ratio (70/30 wt.%) several NaOH/Na2SiO3 ratios and water to AEF substitutions were tested. The best performance was achieved for the alkaline activator having one part of NaOH and three parts of Na2SiO3. According to the main results, the biologic AEF can totally replace the distilled water in the NaOH preparation. Thus will increase the sustainability of the novel materials. Subsequently, the optimized binder was used – with and without AEF - to manufacture mortars with various binder/aggregate ratios. It is concluded that the formulations with a binder/aggregate mass proportion of 1:3 showed the best mechanical performance (compressive strength surpassing 20 MPa, class M20) and the replacement of distilled water with AEF did not affect the specimens final properties, but enhance the materials sustainability. Furthermore, in the pursuit of sustainability, manufacture and curing were conducted at ambient conditions (20 °C, 65% RH), avoiding any external source of energy, involving simple, reproducible, and low-cost processes.
-
preparation of clinker from Paper Pulp industry wastes
Journal of Hazardous Materials, 2015Co-Authors: L H Buruberri, M P Seabra, J A LabrinchaAbstract:Abstract The production of Paper Pulp by the Kraft method generates considerable amounts of wastes. Namely, lime mud generated in the recovery circuit of chemical reagents, biological sludge from the wastewater treatment of wood digestion process and fly ash collected in the fluidized bed combustor used to generate electricity from biomass burning. The final destination of such wastes is an important concern, since environmental regulations are becoming stricter regarding their landfill. Driven by this fact, industries are looking for more sustainable solutions, such as the recycling in distinct products. This work tested these wastes as secondary raw materials to produce clinker/cement that was then experienced in mortar formulations. The first step involved the residues detailed characterization and a generated amounts survey. Then, specific but simple steps were suggested, aiming to facilitate transport and manipulation. Distinct blends were prepared and fired in order to get belitic and Portland clinkers. The Portland clinkers were processed at lower temperatures than the normally used in the industry due to the presence of mineralizing impurities in some wastes. Belite-based cements were used to produce mortars that developed satisfactory mechanical strength and did not reveal signs of deterioration or durability weaknesses.
Ángel T. Martínez - One of the best experts on this subject based on the ideXlab platform.
-
SPRUCE Pulp TREATMENT WITH AN ESTERASE FROM Ophiostoma piceae SIGNIFICANTLY DECREASES THE CONTENT OF BOTH TRIGLYCERIDES AND STEROL ESTERS RESPONSIBLE FOR PITCH DEPOSITS
2016Co-Authors: Olga Calero-rueda, José C. Del Río, Ángel T. Martínez, Ana Gutiérrez, María JAbstract:An esterase has been isolated from the ascomycete Ophiostoma piceae showing high affinity (Km around 1 mM) and activity on both glycerol and sterol esters of long chain fatty acids (kcat around 290 s-1 for triolein and 138 s-1 for cholesteryl oleate). This enzyme could have high potential for the enzymatic control of pitch in Paper Pulp manufacturing from different raw materials. Northern spruce (Picea abies) Pulp containing triglycerides and sterol esters as the main lipophilic compounds, was treated with the O. piceae esterase (a control with boiled enzyme was included). The treated Pulps were lyophilized, Soxhlet extracted with acetone, and the chloroform soluble compounds analyzed by gas chromatography-mass spectrometry. After 3-h treatment, 87 % of triglycerides and 46 % of sterols esters in the spruce Pulp were degraded by the O. piceae esterase. These results suggest that O. piceae esterase could be used for pitch biocontrol in both hardwood and softwood Paper Pulp manufacturin
-
Towards industrially-feasible delignification and pitch removal by treating Paper Pulp with Myceliophthora thermophila laccase and a phenolic mediator
Bioresource technology, 2011Co-Authors: Esteban D. Babot, Alejandro Rico, Jorge Rencoret, Lisbeth Kalum, Henrik Lund, Javier Romero, José C. Del Río, Ángel T. Martínez, Ana GutiérrezAbstract:The ability of two natural phenols to act as mediators of the recombinant Myceliophthora thermophila laccase (MtL) in eucalypt-Pulp delignification was investigated. After alkaline peroxide extraction, the properties of the enzymatically-treated Pulps improved with respect to the control. The Pulp brightness increased (3.1 points) after the enzymatic treatment with MtL alone, but the highest improvements were obtained after the MtL treatment using syringaldehyde (4.7 points) and especially methyl syringate (8.3 points) as mediators. Likewise, a decrease in kappa number up to 2.7 points was obtained after the MtL– methyl syringate treatment, followed by decreases of 1.4 and 0.9 points after the treatments with MtL– syringaldehyde and MtL alone, respectively. On the other hand, removal of the main lipophilic extractives present in eucalypt Pulp was observed after the above laccase–mediator treatments. Finally, the doses of both MtL and methyl syringate were reduced, and results compatible with industrial implementation were obtained.
-
enzymatic delignification of plant cell wall from nature to mill
Current Opinion in Biotechnology, 2009Co-Authors: Ángel T. Martínez, Maria Jesus Martinez, Francisco J Ruizduenas, Ana GutiérrezAbstract:Lignin removal is a central issue in Paper Pulp manufacture, and production of other renewable chemicals, materials, and biofuels in future lignocellulose biorefineries. Biotechnology can contribute to more efficient and environmentally sound deconstruction of plant cell wall by providing tailor-made biocatalysts based on the oxidative enzymes responsible for lignin attack in Nature. With this purpose, the already-known ligninolytic oxidoreductases are being improved using (rational and random-based) protein engineering, and still unknown enzymes will be identified by the application of the different ‘omics’ technologies. Enzymatic delignification will be soon at the Pulp mill (combined with pitch removal) and our understanding of the reactions produced will increase by using modern techniques for lignin analysis.
-
Oxidative degradation of model lipids representative for main Paper Pulp lipophilic extractives by the laccase-mediator system
Applied Microbiology and Biotechnology, 2008Co-Authors: Setefilla Molina, Eric Record, Anne Lomascolo, Jorge Rencoret, José C. Del Río, Ángel T. Martínez, Ana GutiérrezAbstract:Different model lipids—alkanes, fatty alcohols, fatty acids, resin acids, free sterols, sterol esters, and triglycerides—were treated with Pycnoporus cinnabarinus laccase in the presence of 1-hydroxybenzotriazole as mediator, and the products were analyzed by gas chromatography. The laccase alone decreased the concentration of some unsaturated lipids. However, the most extensive lipid modification was obtained with the laccase–mediator system. Unsaturated lipids were largely oxidized and the dominant products detected were epoxy and hydroxy fatty acids from fatty acids and free and esterified 7-ketosterols and steroid ketones from sterols and sterol esters. The former compounds suggested unsaturated lipid attack via the corresponding hydroperoxides. The enzymatic reaction on sterol esters largely depended on the nature of the fatty acyl moiety, i.e., oxidation of saturated fatty acid esters started at the sterol moiety, whereas the initial attack of unsaturated fatty acid esters was produced on the fatty acid double bonds. In contrast, saturated lipids were not modified, although some of them decreased when the laccase–mediator reactions were carried out in the presence of unsaturated lipids suggesting participation of lipid peroxidation radicals. These results are discussed in the context of enzymatic control of pitch to explain the removal of lipid mixtures during laccase–mediator treatment of different Pulp types.
-
removal of lipophilic extractives from Paper Pulp by laccase and lignin derived phenols as natural mediators
Environmental Science & Technology, 2007Co-Authors: Ana Gutiérrez, Jorge Rencoret, Javier Romero, José C. Del Río, David Ibarra, Susana Camarero, Setefilla Molina, Ángel T. MartínezAbstract:In this Paper, we show for the first time that lignin-derived phenols can act as laccase mediators for the removal of lipophilic compounds from Paper Pulp. These natural mediators represent an alternative to synthetic mediators, such as 1-hydroxybenzotriazole (HBT), that cause some economic and environmental concerns. Unbleached kraft Pulp from eucalypt wood, which contained free and conjugated sterols responsible for pitch deposition in the manufacture of totally chlorine free Paper, was treated with a fungal laccase in the presence of syringaldehyde, acetosyringone, and p-coumaric acid as mediators. The composition of lipophilic extractives in the Pulps after the enzymatic treatment followed by a hydrogen peroxide stage was analyzed by gas chromatography and gas chromatography/mass spectrometry. The enzymatic treatment using syringaldehyde as laccase mediator caused the highest removal (over 90%) of free and conjugated sitosterol, similar to that attained with HBT, followed by acetosyringone (over 60% r...
Ana Gutiérrez - One of the best experts on this subject based on the ideXlab platform.
-
SPRUCE Pulp TREATMENT WITH AN ESTERASE FROM Ophiostoma piceae SIGNIFICANTLY DECREASES THE CONTENT OF BOTH TRIGLYCERIDES AND STEROL ESTERS RESPONSIBLE FOR PITCH DEPOSITS
2016Co-Authors: Olga Calero-rueda, José C. Del Río, Ángel T. Martínez, Ana Gutiérrez, María JAbstract:An esterase has been isolated from the ascomycete Ophiostoma piceae showing high affinity (Km around 1 mM) and activity on both glycerol and sterol esters of long chain fatty acids (kcat around 290 s-1 for triolein and 138 s-1 for cholesteryl oleate). This enzyme could have high potential for the enzymatic control of pitch in Paper Pulp manufacturing from different raw materials. Northern spruce (Picea abies) Pulp containing triglycerides and sterol esters as the main lipophilic compounds, was treated with the O. piceae esterase (a control with boiled enzyme was included). The treated Pulps were lyophilized, Soxhlet extracted with acetone, and the chloroform soluble compounds analyzed by gas chromatography-mass spectrometry. After 3-h treatment, 87 % of triglycerides and 46 % of sterols esters in the spruce Pulp were degraded by the O. piceae esterase. These results suggest that O. piceae esterase could be used for pitch biocontrol in both hardwood and softwood Paper Pulp manufacturin
-
Towards industrially-feasible delignification and pitch removal by treating Paper Pulp with Myceliophthora thermophila laccase and a phenolic mediator
Bioresource technology, 2011Co-Authors: Esteban D. Babot, Alejandro Rico, Jorge Rencoret, Lisbeth Kalum, Henrik Lund, Javier Romero, José C. Del Río, Ángel T. Martínez, Ana GutiérrezAbstract:The ability of two natural phenols to act as mediators of the recombinant Myceliophthora thermophila laccase (MtL) in eucalypt-Pulp delignification was investigated. After alkaline peroxide extraction, the properties of the enzymatically-treated Pulps improved with respect to the control. The Pulp brightness increased (3.1 points) after the enzymatic treatment with MtL alone, but the highest improvements were obtained after the MtL treatment using syringaldehyde (4.7 points) and especially methyl syringate (8.3 points) as mediators. Likewise, a decrease in kappa number up to 2.7 points was obtained after the MtL– methyl syringate treatment, followed by decreases of 1.4 and 0.9 points after the treatments with MtL– syringaldehyde and MtL alone, respectively. On the other hand, removal of the main lipophilic extractives present in eucalypt Pulp was observed after the above laccase–mediator treatments. Finally, the doses of both MtL and methyl syringate were reduced, and results compatible with industrial implementation were obtained.
-
enzymatic delignification of plant cell wall from nature to mill
Current Opinion in Biotechnology, 2009Co-Authors: Ángel T. Martínez, Maria Jesus Martinez, Francisco J Ruizduenas, Ana GutiérrezAbstract:Lignin removal is a central issue in Paper Pulp manufacture, and production of other renewable chemicals, materials, and biofuels in future lignocellulose biorefineries. Biotechnology can contribute to more efficient and environmentally sound deconstruction of plant cell wall by providing tailor-made biocatalysts based on the oxidative enzymes responsible for lignin attack in Nature. With this purpose, the already-known ligninolytic oxidoreductases are being improved using (rational and random-based) protein engineering, and still unknown enzymes will be identified by the application of the different ‘omics’ technologies. Enzymatic delignification will be soon at the Pulp mill (combined with pitch removal) and our understanding of the reactions produced will increase by using modern techniques for lignin analysis.
-
Oxidative degradation of model lipids representative for main Paper Pulp lipophilic extractives by the laccase-mediator system
Applied Microbiology and Biotechnology, 2008Co-Authors: Setefilla Molina, Eric Record, Anne Lomascolo, Jorge Rencoret, José C. Del Río, Ángel T. Martínez, Ana GutiérrezAbstract:Different model lipids—alkanes, fatty alcohols, fatty acids, resin acids, free sterols, sterol esters, and triglycerides—were treated with Pycnoporus cinnabarinus laccase in the presence of 1-hydroxybenzotriazole as mediator, and the products were analyzed by gas chromatography. The laccase alone decreased the concentration of some unsaturated lipids. However, the most extensive lipid modification was obtained with the laccase–mediator system. Unsaturated lipids were largely oxidized and the dominant products detected were epoxy and hydroxy fatty acids from fatty acids and free and esterified 7-ketosterols and steroid ketones from sterols and sterol esters. The former compounds suggested unsaturated lipid attack via the corresponding hydroperoxides. The enzymatic reaction on sterol esters largely depended on the nature of the fatty acyl moiety, i.e., oxidation of saturated fatty acid esters started at the sterol moiety, whereas the initial attack of unsaturated fatty acid esters was produced on the fatty acid double bonds. In contrast, saturated lipids were not modified, although some of them decreased when the laccase–mediator reactions were carried out in the presence of unsaturated lipids suggesting participation of lipid peroxidation radicals. These results are discussed in the context of enzymatic control of pitch to explain the removal of lipid mixtures during laccase–mediator treatment of different Pulp types.
-
removal of lipophilic extractives from Paper Pulp by laccase and lignin derived phenols as natural mediators
Environmental Science & Technology, 2007Co-Authors: Ana Gutiérrez, Jorge Rencoret, Javier Romero, José C. Del Río, David Ibarra, Susana Camarero, Setefilla Molina, Ángel T. MartínezAbstract:In this Paper, we show for the first time that lignin-derived phenols can act as laccase mediators for the removal of lipophilic compounds from Paper Pulp. These natural mediators represent an alternative to synthetic mediators, such as 1-hydroxybenzotriazole (HBT), that cause some economic and environmental concerns. Unbleached kraft Pulp from eucalypt wood, which contained free and conjugated sterols responsible for pitch deposition in the manufacture of totally chlorine free Paper, was treated with a fungal laccase in the presence of syringaldehyde, acetosyringone, and p-coumaric acid as mediators. The composition of lipophilic extractives in the Pulps after the enzymatic treatment followed by a hydrogen peroxide stage was analyzed by gas chromatography and gas chromatography/mass spectrometry. The enzymatic treatment using syringaldehyde as laccase mediator caused the highest removal (over 90%) of free and conjugated sitosterol, similar to that attained with HBT, followed by acetosyringone (over 60% r...
Manfredi Saeli - One of the best experts on this subject based on the ideXlab platform.
-
innovative recycling of lime slaker grits from Paper Pulp industry reused as aggregate in ambient cured biomass fly ash based geopolymers for sustainable construction material
Sustainability, 2019Co-Authors: Manfredi Saeli, L Senff, D M Tobaldi, Giada La Scalia, M P Seabra, J A LabrinchaAbstract:Lime slaker grits and biomass fly ash are solid wastes produced by the Kraft Paper-Pulp industry that are commonly disposed of in landfill. However, recent studies and European regulations discourage such disposal practices. This work investigates an alternative and innovative way to recycle and reuse these wastes in the production of green geopolymeric mortars intended for application in the construction industry. Here, biomass fly ash was used as the main source of alumino-silicate in the binder precursor (70 wt.% substitution to metakaolin), and grits (ranging from 1–12.5 mm, as provided by the industry) were reused as aggregate. Aggregate granulometry was also completed by using a commercial natural siliceous sand (<1 mm). Mortars using sand only were prepared for comparative reasons. The implemented mix was designed to investigate the influence of the grits on the mortar’s properties such as its binder/aggregate ratio, workability, bulk density, water sorptivity, and compressive strength. At the same time, waste reuse was analysed in light of its limitations and potentialities. Moreover, in the pursuit of sustainability, the manufacturing process that was followed was highly cost-effective in ambient curing conditions (20 °C, 65% RH), which avoided the use of any external source of energy as commonly used in geopolymers processing. The achieved results proved that the combined use of these wastes, which to date has hardly been explored, along with ambient manufacturing conditions increases the material sustainability. The produced mortars are suitable for innovative applications in various fields, with a particular focus on construction and contribute to the circular economy.
-
mix design and mechanical performance of geopolymeric binders and mortars using biomass fly ash and alkaline effluent from Paper Pulp industry
Journal of Cleaner Production, 2019Co-Authors: Manfredi Saeli, D M Tobaldi, M P Seabra, J A LabrinchaAbstract:Abstract This work investigates the use of biomass fly ash (BFA) and an alkaline effluent (AEF), both generated from the Kraft Pulp industry, in the preparation of geopolymeric binders and mortars for construction applications. BFA replaced the metakaolin (MK) while the AEF substituted the distilled water used to dissolve NaOH pellets. The mix design aims to maximize the amount of both the wastes and to optimize the materials properties, such as workability and mechanical performance. At the same time, also the environmental impact decreases enhancing the materials' sustainability and facilitating the circular economy. For the previously optimized BFA/MK ratio (70/30 wt.%) several NaOH/Na2SiO3 ratios and water to AEF substitutions were tested. The best performance was achieved for the alkaline activator having one part of NaOH and three parts of Na2SiO3. According to the main results, the biologic AEF can totally replace the distilled water in the NaOH preparation. Thus will increase the sustainability of the novel materials. Subsequently, the optimized binder was used – with and without AEF - to manufacture mortars with various binder/aggregate ratios. It is concluded that the formulations with a binder/aggregate mass proportion of 1:3 showed the best mechanical performance (compressive strength surpassing 20 MPa, class M20) and the replacement of distilled water with AEF did not affect the specimens final properties, but enhance the materials sustainability. Furthermore, in the pursuit of sustainability, manufacture and curing were conducted at ambient conditions (20 °C, 65% RH), avoiding any external source of energy, involving simple, reproducible, and low-cost processes.
Sudharsan Sadhasivam - One of the best experts on this subject based on the ideXlab platform.
-
deployment of trichoderma harzianum wl1 laccase in Pulp bleaching and Paper industry effluent treatment
Journal of Cleaner Production, 2010Co-Authors: Sudharsan Sadhasivam, S Savitha, Krishnasamy SwaminathanAbstract:Abstract The ability of Trichoderma harzianum WL1 crude laccase and the fungal system for the biobleaching of wastePaper Pulp and treatment of Paper industry effluent was investigated. Three different modes of treatment, enzyme, enzyme-alkali and enzyme-EDED were employed for the bleaching of wastePaper Pulp. The process parameters such as treatment period, Pulp consistency, temperature and enzyme charge had a great influence on the quality of Paper Pulp. The Paper industry effluent was subjected to eight different treatments via. aerobic, anaerobic, fungal and combination of these treatments. Fungal followed by anaerobic treatment was found to be effective in Paper industry effluent treatment.
-
deployment of trichoderma harzianum wl1 laccase in Pulp bleaching and Paper industry effluent treatment
Journal of Cleaner Production, 2010Co-Authors: Sudharsan Sadhasivam, S Savitha, Krishnasamy SwaminathanAbstract:Abstract The ability of Trichoderma harzianum WL1 crude laccase and the fungal system for the biobleaching of wastePaper Pulp and treatment of Paper industry effluent was investigated. Three different modes of treatment, enzyme, enzyme-alkali and enzyme-EDED were employed for the bleaching of wastePaper Pulp. The process parameters such as treatment period, Pulp consistency, temperature and enzyme charge had a great influence on the quality of Paper Pulp. The Paper industry effluent was subjected to eight different treatments via. aerobic, anaerobic, fungal and combination of these treatments. Fungal followed by anaerobic treatment was found to be effective in Paper industry effluent treatment.
