In Chile, bamboo bushes of Chusquea quila genus (or popularly known as ‘quila’) have brought econ... more In Chile, bamboo bushes of Chusquea quila genus (or popularly known as ‘quila’) have brought economic and ecological problems for decades in the south-central part of this country. On the other hand, this plant species was studied as a raw material for the production of nanofibrillated cellulose (CNF) and nanocrystalline cellulose (CNC), presenting an opportunity for sustainable and environmentally friendly management, positioning Chile as a Latin American country at the forefront of studies with nanotechnological approaches. The methodology applied to generate these nanostructures contemplated hydrolysis with sulfuric acid and oxalic acid, in addition to an intermediate stage of microfluidization to generate nanofibrillated cellulose. The products obtained showed morphological and topographic homogeneity in the scanning electron microscopy (SEM) and atomic force microscopy (AFM) images. The diameter values of the particles ranged from 10 to 20 nanometers for the CNCs. Through Fouri...
Quila (Chusquea quila) is a very abundant native Chilean bamboo species. This work reports on a d... more Quila (Chusquea quila) is a very abundant native Chilean bamboo species. This work reports on a delignification process which can be applied to quila to produce crystalline cellulose, an important resource for obtaining cellulose nanofibres or nanocrystals. Alternatively, the crystalline cellulose can then be subjected to fermentation processes, making it a useful raw material for biofuel production. The treatment studied is an oxidative treatment at low concentration (15% v/v), for short time periods (10, 20 min) and at temperatures between 100 and 140 °C, which produces alpha-cellulose fibres with high crystallinity (over 70%) and low residual lignin content (< 2%). The morphology of the cellulose fibres was analysed by scanning electron microscope, revealing a smooth surface containing many fibrils. Infrared spectroscopy was used to identify functional groups, showing that almost 99% of the lignin was removed. The crystallinity index of the cellulose fibres after the reaction ...
Environmental Engineering and Management Journal, 2017
ABSTRACT This study assesses the feasibility of using the filamentous fungus Fusarium solani for ... more ABSTRACT This study assesses the feasibility of using the filamentous fungus Fusarium solani for the removal of colour, chemical oxygen demand (COD) and total phenols from a pulp mill industry effluent, inoculated in a rotating biological contactor (RBC). The study was done in a RBC of total volume 7.2 L, operated with 40% of useful volume at 37(±2)°C, inflow 3.5 L d-1, hydraulic residence time (HRT) 20 h and rotation speed 2 rpm. A Haldane model was used to determine the kinetic parameters of F. solani with a model effluent. The results show maximum elimination capacities and removal efficiencies for COD and phenols of 2921 mg m-2 d-1 (84%) and 72 mg m-2 d-1 (83%), respectively. Colour removal efficiencies of 60% (equivalent to 32 colour units, CU) were also obtained. The kinetic results show COD inhibition at concentrations above 110 mg L-1.
The low solubility of hydrophobic volatile organic compounds (VOCs) is one of the main problems f... more The low solubility of hydrophobic volatile organic compounds (VOCs) is one of the main problems for their treatment in biofilters. However, this obstacle may be reduced using fungi. Otherwise they may produce spores, under some conditions, that could present some health hazard if nor contained. The aim of this work was to study the effect of operating temperature and humidity of the filter bed in the spores generation of Fusarium solani in the hydrophobic VOCs biofiltrarion.
ABSTRACT The aim of this study is to evaluate the effect of the lignin content in four hybrid pop... more ABSTRACT The aim of this study is to evaluate the effect of the lignin content in four hybrid poplars for enhancing ethanol production. The study was conducted using steam explosion at 200 and 220°C for 5 min as a pre-treatment and then a simultaneous saccharification and fermentation (SSF) process with Saccharomyces cerevisiae. The composition of raw material, liquid and solid fraction obtained after pretreatment, enzymatic digestion, and ethanol production under the different experimental conditions were analyzed. The best results for bioethanol production were obtained from steam explosion pre-treatment carried out at 220°C with the hybrid poplar H-29, with cellulose recovery of over 63%, enzymatic hydrolysis yield of approximately 67%, and SSF yield of 70% of the theoretical value. However, the highest enzymatic hydrolysis yield (79%) was obtained for the hybrid poplar H-34, which has the lowest lignin content.
SUMMARY Hexenuronic acid (HexA) formed in alkaline pulping is known to react with bleaching agent... more SUMMARY Hexenuronic acid (HexA) formed in alkaline pulping is known to react with bleaching agents, leading to increased production costs, and affecting product quality and environmental performance. This article focuses on environmental implications of HexA removal from ...
Thermal insulation is probably one of the most important elements in reducing the heating demands... more Thermal insulation is probably one of the most important elements in reducing the heating demands of residential accommodation in a cool temperate climate. However many insulating materials have a large environmental impact and high embodied energy. Research has shown that natural fibres can provide insulation with a lower impact especially when sourced locally. This paper presents a study of the natural fibres with insulating potential available in the micro-region of Araucania Andina in Chile’s 9th Region, a temperate region with long cold wet winters and short hot summers. An environmental impact matrix is used to select the materials with the lowest impact, which in turn are subjected to laboratory guarded hot box testing to determine their thermal conductivity. The final results will inform the design of a sustainable construction system for the micro-region. Materials evaluated include cellulose fibre from the forestry industry which is one of the principal sectors in the loca...
In Chile, bamboo bushes of Chusquea quila have brought economic and ecological problems for decad... more In Chile, bamboo bushes of Chusquea quila have brought economic and ecological problems for decades in the south-central part of this country. On the other hand, this plant species was studied as a raw material for the production of nanofibrillated cellulose (CNF) and nanocrystalline cellulose (CNC), presenting an opportunity for sustainable and environmentally friendly management, positioning Chile as a Latin American country at the forefront of studies with nanotechnological approaches. The methodology applied to generate these nanostructures contemplated hydrolysis with sulfuric acid and oxalic acid, in addition to an intermediate stage of microfluidization to generate nanofibrillated cellulose. The products obtained showed morphological and topographic homogeneity in the scanning electron microscopy (SEM) and atomic force microscopy (AFM) images. The diameter values of the particles ranged from 10 to 20 nanometers for the CNCs. Through Fourier transformed spectrophotometry (FTIR...
Abstract Polymers of renewable origin have aroused great interest among researchers due to their ... more Abstract Polymers of renewable origin have aroused great interest among researchers due to their sustainable, environmentally friendly nature. This work presents a biopolymer called bio-tissue, as it is created by electrospinning. This bio-tissue was formed with a polymer matrix of cellulose acetate (CA) reinforced with crystalline cellulose (NCC) derived from an autochthonous Chilean bamboo species of no commercial value which is considered a pest, Chusquea quila or quila. Bio-tissues were produced with three concentrations of NCC (1, 5 and 10% as a dry weight proportion of cellulose acetate) and their technological potential as an interior coating in small constructions was assessed. The morphology of the bio-tissues showed that the CA nanofibers containing NCC were of better quality and more uniform diameter than pure CA. The thermal profile showed that the highest concentration of NCC (10% as a dry weight proportion of cellulose acetate) induced earlier degradation; it was less thermally stable and decomposed at lower temperatures. The bio-tissue with 5% as a dry weight proportion of cellulose acetate showed the greatest resistance to traction with a break-point of 30 MPa and an elasticity module of 1.597 MPa. Finally, it was shown that the permeability to water vapour, oxygen and carbon dioxide was low, allowing regulated passage of these molecules. These results show the feasibility of using cellulose nanofibers as a reinforcement in polymer matrices; this could have various applications in fields ranging from the construction industry to food packaging.
Quila (Chusquea quila) is a very abundant native Chilean bamboo species. This work reports on a d... more Quila (Chusquea quila) is a very abundant native Chilean bamboo species. This work reports on a delignifica- tion process which can be applied to quila to produce crys- talline cellulose, an important resource for obtaining cellu- lose nanofibres or nanocrystals. Alternatively, the crystalline cellulose can then be subjected to fermentation processes, making it a useful raw material for biofuel production. The treatment studied is an oxidative treatment at low concen- tration (15% v/v), for short time periods (10, 20 min) and at temperatures between 100 and 140 °C, which produces alpha-cellulose fibres with high crystallinity (over 70%) and low residual lignin content (< 2%). The morphology of the cellulose fibres was analysed by scanning electron microscope, revealing a smooth surface containing many fibrils. Infrared spectroscopy was used to identify functional groups, showing that almost 99% of the lignin was removed. The crystallinity index of the cellulose fibres after the r...
The Science of the total environment, Jan 15, 2017
The objective of this research was to determine emission factors (EF) for particulate matter (PM2... more The objective of this research was to determine emission factors (EF) for particulate matter (PM2.5), combustion gases and particle size distribution generated by the combustion of Eucalyptus globulus (EG), Nothofagus obliqua (NO), both hardwoods, and Pinus radiata (PR), softwood, using a controlled combustion chamber (3CE). Additionally, the contribution of the different emissions stages associated with the combustion of these wood samples was also determined. Combustion experiments were performed using shaving size dried wood (0% humidity). The emission samples were collected with a tedlar bag and sampling cartridges containing quartz fiber filters. High reproducibility was achieved between experiment repetitions (CV<10%, n=3). The EF for PM2.5 was 1.06gkg(-1) for EG, 1.33gkg(-1) for NO, and 0.84gkg(-1) for PR. Using a laser aerosol spectrometer (0.25-34μm), the contribution of particle emissions (PM2.5) in each stage of emission process (SEP) was sampled in real time. Particle...
In Chile, bamboo bushes of Chusquea quila genus (or popularly known as ‘quila’) have brought econ... more In Chile, bamboo bushes of Chusquea quila genus (or popularly known as ‘quila’) have brought economic and ecological problems for decades in the south-central part of this country. On the other hand, this plant species was studied as a raw material for the production of nanofibrillated cellulose (CNF) and nanocrystalline cellulose (CNC), presenting an opportunity for sustainable and environmentally friendly management, positioning Chile as a Latin American country at the forefront of studies with nanotechnological approaches. The methodology applied to generate these nanostructures contemplated hydrolysis with sulfuric acid and oxalic acid, in addition to an intermediate stage of microfluidization to generate nanofibrillated cellulose. The products obtained showed morphological and topographic homogeneity in the scanning electron microscopy (SEM) and atomic force microscopy (AFM) images. The diameter values of the particles ranged from 10 to 20 nanometers for the CNCs. Through Fouri...
Quila (Chusquea quila) is a very abundant native Chilean bamboo species. This work reports on a d... more Quila (Chusquea quila) is a very abundant native Chilean bamboo species. This work reports on a delignification process which can be applied to quila to produce crystalline cellulose, an important resource for obtaining cellulose nanofibres or nanocrystals. Alternatively, the crystalline cellulose can then be subjected to fermentation processes, making it a useful raw material for biofuel production. The treatment studied is an oxidative treatment at low concentration (15% v/v), for short time periods (10, 20 min) and at temperatures between 100 and 140 °C, which produces alpha-cellulose fibres with high crystallinity (over 70%) and low residual lignin content (< 2%). The morphology of the cellulose fibres was analysed by scanning electron microscope, revealing a smooth surface containing many fibrils. Infrared spectroscopy was used to identify functional groups, showing that almost 99% of the lignin was removed. The crystallinity index of the cellulose fibres after the reaction ...
Environmental Engineering and Management Journal, 2017
ABSTRACT This study assesses the feasibility of using the filamentous fungus Fusarium solani for ... more ABSTRACT This study assesses the feasibility of using the filamentous fungus Fusarium solani for the removal of colour, chemical oxygen demand (COD) and total phenols from a pulp mill industry effluent, inoculated in a rotating biological contactor (RBC). The study was done in a RBC of total volume 7.2 L, operated with 40% of useful volume at 37(±2)°C, inflow 3.5 L d-1, hydraulic residence time (HRT) 20 h and rotation speed 2 rpm. A Haldane model was used to determine the kinetic parameters of F. solani with a model effluent. The results show maximum elimination capacities and removal efficiencies for COD and phenols of 2921 mg m-2 d-1 (84%) and 72 mg m-2 d-1 (83%), respectively. Colour removal efficiencies of 60% (equivalent to 32 colour units, CU) were also obtained. The kinetic results show COD inhibition at concentrations above 110 mg L-1.
The low solubility of hydrophobic volatile organic compounds (VOCs) is one of the main problems f... more The low solubility of hydrophobic volatile organic compounds (VOCs) is one of the main problems for their treatment in biofilters. However, this obstacle may be reduced using fungi. Otherwise they may produce spores, under some conditions, that could present some health hazard if nor contained. The aim of this work was to study the effect of operating temperature and humidity of the filter bed in the spores generation of Fusarium solani in the hydrophobic VOCs biofiltrarion.
ABSTRACT The aim of this study is to evaluate the effect of the lignin content in four hybrid pop... more ABSTRACT The aim of this study is to evaluate the effect of the lignin content in four hybrid poplars for enhancing ethanol production. The study was conducted using steam explosion at 200 and 220°C for 5 min as a pre-treatment and then a simultaneous saccharification and fermentation (SSF) process with Saccharomyces cerevisiae. The composition of raw material, liquid and solid fraction obtained after pretreatment, enzymatic digestion, and ethanol production under the different experimental conditions were analyzed. The best results for bioethanol production were obtained from steam explosion pre-treatment carried out at 220°C with the hybrid poplar H-29, with cellulose recovery of over 63%, enzymatic hydrolysis yield of approximately 67%, and SSF yield of 70% of the theoretical value. However, the highest enzymatic hydrolysis yield (79%) was obtained for the hybrid poplar H-34, which has the lowest lignin content.
SUMMARY Hexenuronic acid (HexA) formed in alkaline pulping is known to react with bleaching agent... more SUMMARY Hexenuronic acid (HexA) formed in alkaline pulping is known to react with bleaching agents, leading to increased production costs, and affecting product quality and environmental performance. This article focuses on environmental implications of HexA removal from ...
Thermal insulation is probably one of the most important elements in reducing the heating demands... more Thermal insulation is probably one of the most important elements in reducing the heating demands of residential accommodation in a cool temperate climate. However many insulating materials have a large environmental impact and high embodied energy. Research has shown that natural fibres can provide insulation with a lower impact especially when sourced locally. This paper presents a study of the natural fibres with insulating potential available in the micro-region of Araucania Andina in Chile’s 9th Region, a temperate region with long cold wet winters and short hot summers. An environmental impact matrix is used to select the materials with the lowest impact, which in turn are subjected to laboratory guarded hot box testing to determine their thermal conductivity. The final results will inform the design of a sustainable construction system for the micro-region. Materials evaluated include cellulose fibre from the forestry industry which is one of the principal sectors in the loca...
In Chile, bamboo bushes of Chusquea quila have brought economic and ecological problems for decad... more In Chile, bamboo bushes of Chusquea quila have brought economic and ecological problems for decades in the south-central part of this country. On the other hand, this plant species was studied as a raw material for the production of nanofibrillated cellulose (CNF) and nanocrystalline cellulose (CNC), presenting an opportunity for sustainable and environmentally friendly management, positioning Chile as a Latin American country at the forefront of studies with nanotechnological approaches. The methodology applied to generate these nanostructures contemplated hydrolysis with sulfuric acid and oxalic acid, in addition to an intermediate stage of microfluidization to generate nanofibrillated cellulose. The products obtained showed morphological and topographic homogeneity in the scanning electron microscopy (SEM) and atomic force microscopy (AFM) images. The diameter values of the particles ranged from 10 to 20 nanometers for the CNCs. Through Fourier transformed spectrophotometry (FTIR...
Abstract Polymers of renewable origin have aroused great interest among researchers due to their ... more Abstract Polymers of renewable origin have aroused great interest among researchers due to their sustainable, environmentally friendly nature. This work presents a biopolymer called bio-tissue, as it is created by electrospinning. This bio-tissue was formed with a polymer matrix of cellulose acetate (CA) reinforced with crystalline cellulose (NCC) derived from an autochthonous Chilean bamboo species of no commercial value which is considered a pest, Chusquea quila or quila. Bio-tissues were produced with three concentrations of NCC (1, 5 and 10% as a dry weight proportion of cellulose acetate) and their technological potential as an interior coating in small constructions was assessed. The morphology of the bio-tissues showed that the CA nanofibers containing NCC were of better quality and more uniform diameter than pure CA. The thermal profile showed that the highest concentration of NCC (10% as a dry weight proportion of cellulose acetate) induced earlier degradation; it was less thermally stable and decomposed at lower temperatures. The bio-tissue with 5% as a dry weight proportion of cellulose acetate showed the greatest resistance to traction with a break-point of 30 MPa and an elasticity module of 1.597 MPa. Finally, it was shown that the permeability to water vapour, oxygen and carbon dioxide was low, allowing regulated passage of these molecules. These results show the feasibility of using cellulose nanofibers as a reinforcement in polymer matrices; this could have various applications in fields ranging from the construction industry to food packaging.
Quila (Chusquea quila) is a very abundant native Chilean bamboo species. This work reports on a d... more Quila (Chusquea quila) is a very abundant native Chilean bamboo species. This work reports on a delignifica- tion process which can be applied to quila to produce crys- talline cellulose, an important resource for obtaining cellu- lose nanofibres or nanocrystals. Alternatively, the crystalline cellulose can then be subjected to fermentation processes, making it a useful raw material for biofuel production. The treatment studied is an oxidative treatment at low concen- tration (15% v/v), for short time periods (10, 20 min) and at temperatures between 100 and 140 °C, which produces alpha-cellulose fibres with high crystallinity (over 70%) and low residual lignin content (< 2%). The morphology of the cellulose fibres was analysed by scanning electron microscope, revealing a smooth surface containing many fibrils. Infrared spectroscopy was used to identify functional groups, showing that almost 99% of the lignin was removed. The crystallinity index of the cellulose fibres after the r...
The Science of the total environment, Jan 15, 2017
The objective of this research was to determine emission factors (EF) for particulate matter (PM2... more The objective of this research was to determine emission factors (EF) for particulate matter (PM2.5), combustion gases and particle size distribution generated by the combustion of Eucalyptus globulus (EG), Nothofagus obliqua (NO), both hardwoods, and Pinus radiata (PR), softwood, using a controlled combustion chamber (3CE). Additionally, the contribution of the different emissions stages associated with the combustion of these wood samples was also determined. Combustion experiments were performed using shaving size dried wood (0% humidity). The emission samples were collected with a tedlar bag and sampling cartridges containing quartz fiber filters. High reproducibility was achieved between experiment repetitions (CV<10%, n=3). The EF for PM2.5 was 1.06gkg(-1) for EG, 1.33gkg(-1) for NO, and 0.84gkg(-1) for PR. Using a laser aerosol spectrometer (0.25-34μm), the contribution of particle emissions (PM2.5) in each stage of emission process (SEP) was sampled in real time. Particle...
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