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1.
Ital J Pediatr ; 50(1): 138, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39080772

RESUMEN

BACKGROUND: Elexacaftor-tezacaftor-ivacaftor (ETI) is a transmembrane conductance regulator modulator that significantly improves lung function in patients affected by cystic fibrosis (CF). This triple drug is currently not indicated in liver transplant patients, as clinical trials including subjects with previous solid organ transplantation are lacking. CASE PRESENTATION: We report on a liver transplant girl with CF-related advanced pulmonary disease meeting clinical criteria for lung transplant, who started the triple modulator because she could not get on the lung transplant waiting list due to psycho-social motivations. Since initiation of ETI therapy, she has experienced a significant improvement in respiratory function and quality of life, without adverse effects. CONCLUSIONS: This case shows that ETI therapy can represent a lifesaving drug for individuals without alternatives, even in liver transplant patients. The clinical benefits of the modulator overcome risks, which may be limited with a close drug monitoring of immunosuppressants serum levels and functional liver tests.


Asunto(s)
Benzodioxoles , Indoles , Trasplante de Hígado , Trasplante de Pulmón , Pirazoles , Piridinas , Femenino , Humanos , Aminofenoles/uso terapéutico , Benzodioxoles/uso terapéutico , Combinación de Medicamentos , Indoles/uso terapéutico , Pirazoles/uso terapéutico , Piridinas/uso terapéutico , Quinolinas/uso terapéutico , Quinolonas/uso terapéutico , Listas de Espera , Adolescente
2.
Mar Pollut Bull ; 201: 116270, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38520997

RESUMEN

Seagrass wrack plays multiple ecological roles in coastal habitats but is often removed from beaches and used for economical processing, neglecting its potential role in sustaining dune plant establishment under changing climate scenarios. Rainwater shortage is a major stress for seedlings and reduced precipitations are expected in some coastal areas. We investigated in mesocosm how wrack influenced seedling performance of Cakile maritima, Thinopyrum junceum, and Calamagrostis arenaria under current and reduced precipitation. We also assessed wrack water holding capacity and leachate chemical/physical properties. Wrack stimulated seedling growth while reduced precipitation decreased root development. Wrack mitigated the effects of reduced precipitation on T. junceum and C. arenaria biomass. Wrack retained water up to five-fold its weight, increased water pH, conductivity, and nutrient content. Wrack promotes dune colonization by vegetation even under rainwater shortage. Thus, the maintenance of this natural resource on beaches is critical for improving dune resilience against climate changes.


Asunto(s)
Ecosistema , Plantas , Poaceae , Plantones , Recursos Naturales , Cambio Climático , Agua
3.
ACS Sustain Chem Eng ; 11(32): 12014-12026, 2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37593378

RESUMEN

This work is focused on the application of Life Cycle Assessment (LCA) methodology for the quantification of the potential environmental impacts associated with the obtainment of levulinic acid from residual Cynara cardunculus L. biomass and its subsequent valorization in innovative bioplasticizers for tuning the properties as well as the processability of biopolymers. This potentially allows the production of fully biobased and biodegradable bioplastic formulations, thus addressing the issues related to the fossil origin and nonbiodegradability of conventional additives, such as phthalates. Steam explosion pretreatment was applied to the epigean residue of C. cardunculus L. followed by a microwave-assisted acid-catalyzed hydrolysis. After purification, the as-obtained levulinic acid was used to synthesize different ketal-diester derivatives through a three-step selective synthesis. The levulinic acid-base additives demonstrated remarkable plasticizing efficiency when added to biobased plastics. The LCA results were used in conjunction with those from the experimental activities to find the optimal compromise between environmental impacts and mechanical and thermal properties, induced by the bioadditives in poly(3-hydroxybutyrate), PHB biopolymer.

4.
Waste Manag ; 168: 235-245, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37320891

RESUMEN

Levulinic acid production by acid-catalyzed hydrothermal conversion of (ligno)cellulosic biomass generates significant amounts of carbonaceous hydrochar, which is currently considered a final waste. In this work, the hydrochar recovered after the levulinic acid production, was subjected to cascade pyrolysis and chemical activation treatments (by H3PO4 or KOH), to synthesize activated carbons. The pyrolysis post-treatment was already effective in improving the surface properties of the raw hydrochar (Specific Surface Area: 388 m2/g, VP: 0.22 cm3/g, VMESO: 0.07 cm3/g, VMICRO: 0.14 cm3/g), by removing volatile compounds. KOH activation resulted as the most appropriate for further improving the surface properties of the pyrolyzed hydrochar, showing the best surface properties (Specific Surface Area: 1421 m2/g, VP: 0.63 cm3/g, VMESO: 0.10 cm3/g, VMICRO: 0.52 cm3/g), which synergistically makes it a promising system towards adsorption of CO2 (∼90 mg/g) and methylene blue (∼248 mg/g). In addition, promising surface properties can be achieved after direct chemical activation of the raw hazelnut shells, preferably by H3PO4 (Specific Surface Area: 1918 m2/g, VP: 1.34 cm3/g, VMESO: 0.82 cm3/g, VMICRO: 0.50 cm3/g), but this choice is not the smartest, as it does not allow the valorization of the cellulose fraction to levulinic acid. Our approach paves the way for possible uses of these hydrochars originating from the levulinic acid chain for new environmental applications, thus smartly closing the biorefinery loop of the hazelnut shells.


Asunto(s)
Celulosa , Carbón Orgánico , Carbón Orgánico/química , Ácidos Levulínicos , Azul de Metileno , Adsorción
5.
Ital J Pediatr ; 49(1): 56, 2023 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-37173776

RESUMEN

BACKGROUND: Preterm birth is a risk factor for a child's neurological development. Preterm children have unusual neurodevelopmental profiles with executive, visual-motor functions, fine and gross motor skills, language and behavior that affect learning. In this study, we analyzed the neurodevelopmental outcomes of a cohort of very low birth weight infants admitted to the Treviso Neonatal Intensive Care Unit (NICU) between 2014 and 2016 and followed up to preschool childhood. METHOD: This is a prospective cohort study. Infants were followed at birth and after NICU discharge at two- and four-year follow-ups. The two-year assessment was conducted with Bayley III, and at four years with the Wechsler Preschool and Primary Scale of Intelligence - III scales and Movement Assessment Battery for Children - 2. RESULTS: The cohort consisted of 207 subjects with a mean gestational age of 28.9 weeks, and a mean birth weight of 1097.2 g. At two years of age, children without disabilities were 90 (59.6%), those with minor disabilities 47 (31.1%), and those with major disabilities 14 (9.3%); at four years, 58.4% of children without previous disabilities, presented problems with verbal tests and manual dexterity: aiming, grasping and balance at movement assessment. There was significant alteration in processing speed (p < 0.001). Furthermore, there was a strong correlation between processing speed and manual dexterity (p < 0.001) and between processing speed and aiming and grasping (p = 0.0059). CONCLUSIONS: We found that more than half the children free of disability at two years, at four years had deficit often involving the oculo-motor coordination and processing speed. These motor profile alterations limit the expression of cognitive abilities and the achievement of expected school performance, thus resulting in behavioral disorders, typical of preterm children. Early professional follow-up could improve the expected educational outcomes.


Asunto(s)
Trastornos Mentales , Nacimiento Prematuro , Lactante , Femenino , Preescolar , Recién Nacido , Humanos , Niño , Estudios Prospectivos , Recién Nacido de muy Bajo Peso , Peso al Nacer , Desarrollo Infantil
6.
Polymers (Basel) ; 15(6)2023 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-36987333

RESUMEN

Arundo donax L samples, before or after aqueous extraction to remove extractives, were subjected to chemical fractionation in H2SO4-catalyzed mixtures of 1-butanol and water. The partial miscibility of 1-butanol and water at room temperature allowed the separation of the three major feedstock components in separate streams (lignin, accumulated in the 1-butanol-rich phase; hemicellulose-derived products, accumulated in the aqueous acidic phase; and cellulose, present in the solid phase). The effects of selected variables (temperature, catalyst concentration, reaction time and 1-butanol content of the reaction media) on variables measuring the solid recovery yield and the compositions of phases from fractionation were measured. Using water-extracted A. donax L as a substrate, the best operational conditions enabled 93.2% hemicellulose removal and 85.4% delignification with limited cellulose solubilization (15%). The experimental results provided key information to assess the proposed process in the scope of biorefineries.

7.
ACS Sustain Chem Eng ; 11(5): 1875-1887, 2023 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-36778524

RESUMEN

In this work, a three-step approach to isolate the main components of lignocellulosic cardoon, lignin and cellulose, was investigated. The raw defatted biomass, Cynara cardunculus, after steam explosion was subjected to a mild organosolv treatment to extract soluble lignin (L1). Then, enzymatic hydrolysis was performed to achieve decomposition of the saccharidic portion into monosaccharides and isolate residual lignin (L2). The fractionation conditions were optimized to obtain a lignin as less degraded as possible and to maximize the yield of enzymatic hydrolysis. Furthermore, the effect of the use of aqueous ammonia as an extraction catalyst on both fractions was studied. Each fraction was characterized by advanced techniques, such as elemental analysis and 31P nuclear magnetic resonance (NMR), 13C-1H two-dimensional (2D)-NMR, attenuated total reflectance-Fourier transform infrared (ATR-FTIR), and UV-vis spectroscopies for lignin and X-ray diffraction (XRD), Klason compositional analysis, elemental analysis, and ATR-FTIR spectroscopy for cellulose-rich fractions. The impact of the cellulose-rich fraction composition and crystallinity was also correlated to the efficiency of the hydrolysis step, performed using the enzymatic complex Cellic CTec3.

8.
Environ Pollut ; 316(Pt 2): 120738, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36435282

RESUMEN

Pollution associated to marine plastic litter is raising increasing concerns due to its potential harmful effects on human health, biota, and coastal ecosystems. However, limited information is available on the degradation behavior of plastics, especially biodegradable ones, in dune habitats. Moreover, the effects of plastics on dune plant growth and ability to withstand environmental stresses and invasion by non-native plants have been largely neglected. This is a particularly relevant issue since biological invasions are major threats to dune ecosystems. In this 18-month study, we examined the degradation behavior of two plastic bags, non-biodegradable (NBP) or biodegradable/compostable (BP), in the dune environment by visual observations and analytical techniques. Concomitantly, we investigated the individual and combined effects of bag type and sand burial (no burial vs. partial burial) on the performance of a native dune plant (Thinopyrum junceum) and an invasive plant (Carpobrotus sp.) and on their interaction. NBP did not show relevant degradation signs over the experimental period as expected. BP exhibited gradual surface modifications and changes in chemical functionality and were almost disintegrated after 18 months. Bags and burial reduced independently T. junceum survival and growth, and most plants died within 8 months of plastic exposure. Bags and burial did not affect Carpobrotus survival. However, burial decreased Carpobrotus growth while NBP increased it. Both plastics increased Carpobrotus competitive ability, and no T. junceum plants survived to co-occurrent Carpobrotus, BP, and burial. These findings indicate that removing all littered plastics from beach-dune systems not only is critical to reduce plastic pollution but also to prevent further spread of invasive species in coastal dunes.


Asunto(s)
Plásticos , Arena , Humanos , Ecosistema , Desarrollo de la Planta , Especies Introducidas
9.
Molecules ; 29(1)2023 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-38202709

RESUMEN

Diphenolic acid, or 4,4-bis(4-hydroxyphenyl)pentanoic acid, represents one of the potentially most interesting bio-products obtainable from the levulinic acid supply-chain. It represents a valuable candidate for the replacement of bisphenol A, which is strongly questioned for its toxicological issues. Diphenolic acid synthesis involves the condensation reaction between phenol and levulinic acid and requires the presence of a Brønsted acid as a catalyst. In this review, the state of the art related to the catalytic issues of its synthesis have been critically discussed, with particular attention to the heterogeneous systems, the reference benchmark being represented by the homogeneous acids. The main opportunities in the field of heterogeneous catalysis are deeply discussed, as well as the bottlenecks to be overcome to facilitate diphenolic acid production on an industrial scale. The regioselectivity of the reaction is a critical point because only the p,p'-isomer is of industrial interest; thus, several strategies aiming at the improvement of the selectivity towards this isomer are considered. The future potential of adopting alkyl levulinates, instead of levulinic acid, as starting materials for the synthesis of new classes of biopolymers, such as new epoxy and phenolic resins and polycarbonates, is also briefly considered.

10.
Chempluschem ; 87(10): e202200189, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35997649

RESUMEN

This work investigated the catalytic high-pressure CO2 pretreatment of giant reed. CO2 is a renewable resource; its use does not generate chemical wastes and it can be easily removed and recycled. The effect of the addition of low concentrations of FeCl3 (0.16 wt %) and PEG 400 (1.0 wt %) on the hemicellulose hydrolysis to xylose and xylo-oligosaccharides (XOS) is reported for the first time. Under the optimised pretreatment conditions, the xylan conversion of 82 mol % and xylose and XOS yields of 43 and 20 mol % were achieved, respectively. The solid residues obtained from different pretreatments were used as the substrate for the enzymatic hydrolysis to give glucose. The total glucose yield achieved under the optimised two-step process was 67.8 mol % with respect to the glucan units in the biomass. The results demonstrated that PEG-assisted FeCl3 -catalysed scCO2 pretreatment can produce xylose- or XOS-rich hydrolysates and improve the enzymatic hydrolysis of biomass.


Asunto(s)
Dióxido de Carbono , Xilosa , Glucanos , Glucosa , Oligosacáridos/química , Xilanos
11.
Chemosphere ; 307(Pt 3): 135997, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35987266

RESUMEN

Hydrothermal carbonization (HTC) is emerging as a promising technology for the management of sewage sludge. The fate of phytosanitary products, Polycyclic aromatic hydrocarbons (PAHs) and PCBs (Polychlorinated biphenyls) after HTC, as well as the formation of dioxins and furans, is still unclear. Moreover, only little information is available on the distribution of heavy metals and major nutrients between the hydrochars and the process water. Here, we aim to contribute to fill these gaps. HTC of sewage sludge from six different wastewater treatment plants has been carried out at 220 °C for 85 min. Feedstock, hydrochars and spent liquor have been then characterized and discussed. HTC is here proven to be a suitable technology for the immobilization of both heavy hydrocarbons and heavy metals, with the exception arsenic, which was also found in the spent liquor at a significant proportion (∼15-∼50%). DDD, DDT, DDE were detected in all sludge samples and their content was reduced by nearly one order of magnitude after the process. HTC is here proven to not be responsible at an appreciable extent of PCBs enrichment of the processed solids. Moreover, the sum of PCDDs and PCDFs in hydrochars never exceeded 20 ng kg-1 s.s. The results obtained encourage further developing of HTC, with the aim to improve the sustainability of sewage sludge management. Additional studies on the environmental impact of hydrochar when used as alternative fuel, as well as soil amendment, could lead to the overcoming of the issues which still hinder these applications.


Asunto(s)
Arsénico , Dioxinas , Metales Pesados , Plaguicidas , Bifenilos Policlorados , Hidrocarburos Policíclicos Aromáticos , Carbono , DDT , Diclorodifenil Dicloroetileno , Furanos , Aguas del Alcantarillado , Suelo , Temperatura , Agua
12.
ChemSusChem ; 15(13): e202200241, 2022 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-35384331

RESUMEN

The depletion of fossil resources is driving the research towards alternative renewable ones. Under this perspective, 5-hydroxymethylfurfural (HMF) represents a key molecule deriving from biomass characterized by remarkable potential as platform chemical. In this work, for the first time, the hydrogenation of HMF in ethanol was selectively addressed towards 2,5-bis(hydroxymethyl)furan (BHMF) or 2,5-bis(hydroxymethyl)tetrahydrofuran (BHMTHF) by properly tuning the reaction conditions in the presence of the same commercial catalyst (Ru/C), reaching the highest yields of 80 and 93 mol%, respectively. These diols represent not only interesting monomers but strategic precursors for two scarcely investigated ethoxylated biofuels, 2,5-bis(ethoxymethyl)furan (BEMF) and 2,5-bis(ethoxymethyl)tetrahydrofuran (BEMTHF). Therefore, the etherification with ethanol of pure BHMF and BHMTHF and of crude BHMF, as obtained from hydrogenation step, substrates scarcely investigated in the literature, was performed with several commercial heterogeneous acid catalysts. Among them, the zeolite HZSM-5 (Si/Al=25) was the most promising system, achieving the highest BEMF yield of 74 mol%. In particular, for the first time, the synthesis of the fully hydrogenated diether BEMTHF was thoroughly studied, and a novel cascade process for the tailored conversion of HMF to the diethyl ethers BEMF and BEMTHF was proposed.


Asunto(s)
Biocombustibles , Furaldehído , Etanol , Furaldehído/análogos & derivados , Furaldehído/química , Furanos/química
13.
Bioresour Technol ; 325: 124635, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33461125

RESUMEN

Giant reed (Arundo donax L.) is a promising source of carbohydrates that can be converted into single cell oil (SCO) by oleaginous yeasts. Microbial conversion of both hemicellulose and cellulose fractions represents the key step for increasing the economic sustainability for SCO production. Lipomyces starkeyi DSM 70,296 was cultivated in two xylose-rich hydrolysates, obtained by the microwave-assisted hydrolysis of hemicellulose catalysed by FeCl3 or Amberlyst-70, and in two glucose-rich hydrolysates obtained by the enzymatic hydrolysis of cellulose. L. starkeyi grew on both undetoxified and partially-detoxified hydrolysates, achieving the lipid content of 30 wt% and yield values in the range 15-24 wt%. For both integrated cascade processes the final production of about 8 g SCO from 100 g biomass was achieved. SCO production through integrated hydrolysis cascade processes represents a promising solution for the effective exploitation of lignocellulosic feedstock from perennial grasses towards new generation biodiesel and other valuable bio-based products.


Asunto(s)
Lipomyces , Fermentación , Poaceae , Xilosa
14.
Bioresour Technol ; 315: 123790, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32707500

RESUMEN

Single cell oil (SCO) represents an outstanding alternative to both fossil sources and vegetable oils from food crops waste. In this work, an innovative two-step process for the conversion of cellulosic paper mill waste into SCO was proposed and optimised. Hydrolysates containing glucose and xylose were produced by enzymatic hydrolysis of the untreated waste. Under the optimised reaction conditions (Cellic® CTec2 25 FPU/g glucan, 48 h, biomass loading 20 g/L), glucose and xylose yields of 95 mol% were reached. The undetoxified hydrolysate was adopted as substrate for a batch-mode fermentation by the oleaginous yeast Lipomyces starkeyi. Lipid yield, content for single cell, production and maximum oil productivity were 20.2 wt%, 37 wt%, 3.7 g/L and 2.0 g/L/d respectively. This new generation oil, obtained from a negative value industrial waste, represents a promising platform chemical for the production of biodiesel, biosurfactants, animal feed and biobased plastics.


Asunto(s)
Lipomyces , Fermentación , Hidrólisis , Azúcares , Levaduras
15.
Bioresour Technol ; 313: 123650, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32585455

RESUMEN

A two-step exploitation of the giant reed cellulose to glucose and levulinic acid, after the complete removal of the hemicellulose fraction, was investigated using FeCl3 as catalyst. In the first step, the microwave-assisted hydrolysis of cellulose to glucose was optimised by response surface methodology analysis, considering the effect of temperature, reaction time and catalyst amount. Under the optimised reaction conditions, the glucose yield was 39.9 mol%. The cellulose-rich residue was also converted by enzymatic hydrolysis, achieving the glucose yield of 39.8 mol%. The exhausted residue deriving from the chemical hydrolysis was further converted to levulinic acid by microwave treatment at harsher reaction conditions. The maximum levulinic acid yield was 64.3 mol%. On the whole, this cascade approach ensured an extensive and sustainable exploitation of the C6 carbohydrates to glucose and levulinic acid, corresponding to about 70 mol% of glucan converted to these valuable bioproducts in the two steps.


Asunto(s)
Celulosa , Microondas , Cloruros , Compuestos Férricos , Glucosa , Calefacción , Hidrólisis , Ácidos Levulínicos , Poaceae
16.
Bioresour Technol ; 293: 122050, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31454732

RESUMEN

The present work aimed to investigate and optimize the selective exploitation of hemicellulose and cellulose fractions of the energy crop Arundo donax L. (giant reed), to give xylose and levulinic acid, respectively. In order to improve the sustainability of this process, a microwave-assisted hydrolysis in the presence of FeCl3 was implemented using as substrate the raw biomass without any pretreatment process. The effects of the hydrolysis reaction conditions, such as temperature, reaction time, salt amount and biomass loading, on giant reed exploitation were investigated. In the first step, under the optimized conditions (150 °C, 2.5 min and 1.6 wt% FeCl3), the xylose yield reached 98.2 mol%. In the second step, under the best conditions (190 °C, 30 min and 2.4 wt% FeCl3), the levulinic acid yield was 57.6 mol%. This novel cascade approach ensured an extensive exploitation of giant reed polysaccharides working in the respect of Green Chemistry principles.


Asunto(s)
Microondas , Xilosa , Biomasa , Cloruros , Compuestos Férricos , Ácidos Levulínicos , Poaceae
17.
Waste Manag ; 93: 1-13, 2019 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-31235045

RESUMEN

Hydrothermal carbonization (HTC) of sewage sludge reduces the waste volume and can be source of energy and valuable products. Furthermore, HTC offers several advantages over conventional dry-thermal pre-treatments, as no prior drying is requested, and the high quality of the char produced promotes applications as energy production and storage, wastewater remediation, and soil amendment. Relationships between char yields, physicochemical properties and process parameters are here analysed, with the aim to provide insight into the choice of the process severity required to fit the desired application. Moreover, presence and fate of heavy metals and organic contaminants are discussed. The highest reaction temperature is the main parameter affecting the physicochemical characteristics of the char produced, while the heating rate governs the heat mass transfer and the rate of intermediates formation. Depolymerization of the biomass results in a reduction of the oxygen to carbon ratio and, therefore, in augmented high heating values, further increased by deposition of 5-(hydroxymethyl)furfural. Recirculation of process water may enhance dehydration reactions and the deposition of degraded polymers, increasing dewaterability and yield, but field trials are recommended to assess the feasibility of this option. An overuse of chars for energy generation purposes would be deleterious for the environmental life cycle. Further research is encouraged to assess the pollutants abatement and their degradation pathways when incorporated in the carbonaceous product, to promote the application of hydrochars as soil amendment, as well as for environmental remediation purposes.


Asunto(s)
Metales Pesados , Aguas del Alcantarillado , Biomasa , Carbono , Aguas Residuales
18.
Bioresour Technol ; 264: 180-189, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29803088

RESUMEN

Levulinic acid is a platform chemical obtained from acid-catalyzed hydrothermal conversion of cellulose-rich biomass. The low amounts of solid biomass which can be handled in the reactor limit the levulinic acid concentration in the aqueous stream, making the economic viability of the aqueous phase process unsuitable for large scale applications. Now a novel approach to biphasic process has been proposed, where a mineral oil has been used as non-solvent for levulinic acid, thus concentrating it in the water phase, reducing the water volume to be processed downstream but at the same time maintaining enough liquid phase to sustain the slurry processability. The work has studied: i) the optimization of the biphasic hydrolysis of corn grain to levulinic acid; ii) the characterization of the recovered oil; iii) the evaluation of the energetic properties of the recovered hydrochar for its exploitation, thus smartly closing the biorefinery cycle.


Asunto(s)
Ácidos Levulínicos , Biomasa , Celulosa , Hidrólisis , Solventes
19.
Bioresour Technol ; 244(Pt 1): 880-888, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28847076

RESUMEN

For the first time, the exploitation of hazelnut shells for the combined production of levulinic acid (LA) and hydrochar was investigated. The optimization of the catalytic hydrothermal treatment was performed both in autoclave and microwave reactor, approaching a maximum LA yield of ∼9-12wt%. Hydrochars recovered with high yield (∼43-47wt%) were characterized by different techniques, including elemental and proximate analysis, heating value, FT-IR, XPS, XRD, SEM-EDX, and SAA. Their "lignite-like" energetic properties make them suitable for the energy recovery within the same biorefinery plant for LA production, thus partially offsetting the cost of the entire process. Alternatively, since the synthesized hydrochars maintain high levels of oxygenated groups, they could be smartly exploited as natural sorbents for environmental applications. The proposed integrated approach makes possible to fully exploit this waste, smartly closing its biorefinery cycle in a sustainable development perspective.


Asunto(s)
Corylus , Ácidos Levulínicos , Carbón Mineral , Calor , Espectroscopía Infrarroja por Transformada de Fourier
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