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1.
Chemosphere ; 357: 141864, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38588901

RESUMO

Sustainable, efficient, and environmentally friendly ways to tailor the carbonaceous materials from bio sources with desired functionalities remain a challenge around the world. In this study, we represent a novel approach to synthesize carbon hybrid material based on Zinc Oxide/carbon (ZnO/C) hybrid systems by catalytic hydrothermal process via crosslinking reaction through nucleation and growth of ZnO particles at the functional groups of oxidized carbon material. This research explored the volarization of Condensed Corn Distillers Soluble (CDS) as a carbon precursor to synthesize biobased carbon spheres. Surface modification of the produced carbon spheres took place using zinc chloride (ZnCl2) during hydrothermal carbonization (HTC). Zinc chloride (ZnCl2) was used to function as a catalyst during HTC and functioned as a ZnO source to synthesize (ZnO/C) hybrid systems. Design Expert software v13 was used to design the hydrothermal carbonization (HTC) experiments and response surface methodology was used to find the optimized conditions for the preparation of carbon hybrid systems. The hydrothermal synthesis process introduced 3D stone like zinc oxide particles onto the carbon matrix. These particles were self-assembled onto the carbon framework to produce carbon hybrid systems with unique physical, chemical, structural and functional properties. Herein, the obtained carbon hybrid systems (ZnO/C) were investigated and discussed in detail. ZnO/C hybrid systems were analyzed for surface morphology using scanning electron microscopy (SEM) that presented a 3D spherical interconnected phase and XRD analyses were used for phase crystallinity that showed new crystalline phases such as hopeite and zincite after the ZnCl2 incorporation. Surface functional groups were also analyzed by FTIR and results confirmed the presence of hydrophilic groups such as -OH, CC, and COOH on the surface of ZnO/C hybrid carbon systems. This study provided the insightful guidance for tailoring novel design of multifunctional carbon material as an adsorbent/catalyst for various applications of sustainable remediation.


Assuntos
Carbono , Recuperação e Remediação Ambiental , Zea mays , Óxido de Zinco , Óxido de Zinco/química , Zea mays/química , Carbono/química , Catálise , Recuperação e Remediação Ambiental/métodos , Compostos de Zinco/química , Propriedades de Superfície , Cloretos/química
2.
ACS Omega ; 8(17): 15422-15440, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37151540

RESUMO

We investigated the thermal conductivity of materials based on pyrolysis temperature, filler loading, filler size, and type of biomass feedstock. Hemp stalk and switchgrass were pyrolyzed at 450, 550, and 650 °C and crushed into 50, 75, and 100 µm particle sizes. Biocarbon fillers (10, 15, and 20 wt %) were added to the bioepoxy polymer matrix. The study showed increased filler loading and particle size increased thermal conductivity-the biocomposite samples with 20 wt % filler loading of 100 µm particle size of the biocarbon obtained at 650 °C showed the maximum thermal conductivity in both hemp biocarbon-filled composites (0.59 W·m-1·K-1) and switchgrass-filled composites (0.58 W·m-1·K-1) with the highest flame time. Biocarbon in biofiber-reinforced polymer composites can improve thermal conductivity and extend the flame time. These findings significantly contribute to developing hemp-based bioepoxy composite materials for thermal applications in various fields. These include insulating materials for buildings and thermal management systems, energy-efficient applications, and help in material selection and product design with a positive environmental impact.

3.
Int J Mol Sci ; 24(7)2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-37047064

RESUMO

Natural fiber-reinforced composites perform poorly when exposed to moisture. Biocarbon has been proven to improve the water-absorbing behavior of natural fiber composites. However, the interaction effect of the design parameters on the biocarbon-filled hemp fiber-reinforced bio-epoxy composites has not been studied. In this study, the effects of the design parameters (pyrolysis temperature, biocarbon particle size, and filler loading) on the water absorptivity and water diffusivity of hemp-reinforced biopolymer composites have been investigated. Biocarbon from the pyrolysis of hemp and switchgrass was produced at 450, 550, and 650 °C. Composite samples with 10 wt.%, 15 wt.%, and 20 wt.% of biocarbon fillers of sizes below 50, 75, and 100 microns were used. The hemp fiber in polymer composites showed a significant influence in its water uptake behavior with the value of water absorptivity 2.41 × 10-6 g/m2.s1/2. The incorporation of biocarbon fillers in the hemp biopolymer composites reduces the average water absorptivity by 44.17% and diffusivity by 42.02%. At the optimized conditions, the value of water absorptivity with hemp biocarbon and switchgrass biocarbon fillers was found to be 0.72 × 10-6 g/m2.s1/2 and 0.73 × 10-6 g/m2.s1/2, respectively. The biocarbon at 650 °C showed the least composite thickness swelling due to its higher porosity and lower surface area. Biocarbon-filled hemp composites showed higher flexural strength and energy at the break due to the enhanced mechanical interlocking between the filler particles and the matrix materials. Smaller filler particle size lowered the composite's water diffusivity, whereas the larger particle size of the biocarbon fillers in composites minimizes the water absorption. Additionally, higher filler loading results in weaker composite tensile energy at the break due to the filler agglomeration, reduced polymer-filler interactions, reduced polymer chain mobility, and inadequate dispersion of the filler.


Assuntos
Cannabis , Água , Fenômenos Químicos , Tamanho da Partícula , Polímeros
4.
Food Chem ; 401: 134120, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36096002

RESUMO

Proteins of low-value and underexplored corn distillers solubles (CDS) have not been considerably valorized. Hence, the influence of one-step enzymatic hydrolysis of proteins with alcalase (A), trypsin (T) or flavourzyme (F) and two steps with AT, TA, AF, FA, TF, or FT was assessed to release peptides with angiotensin-I converting enzyme inhibition (ACEi) and dipeptidyl peptidase4 inhibition (DPP4i). The AF hydrolysate was the best sample in terms of yield, protein content, degree of hydrolysis, ACEi (97.68 ± 1.09 %), and DPP4i (51.51 ± 0.28 %). Mass spectrometry of the most active AF hydrolysate (<3 kDa) identified new major peptides like APLA, PLFP, LFLP, LPPYL, PLYPLP, NDWHTGPL, LPPYLPS, GSPFLGQ, SWQQPIVGG. Bioinformatic analysis showed these can inhibit both ACE and DPP4. This is because peptides contain functional groups and adopt conformations significantly binding with other functional groups at enzyme active sites (p < 0.05). This establishes dual bioactivity of peptides, which may have applications in food, feed, and pharmaceutical industries.


Assuntos
Hidrolisados de Proteína , Zea mays , Hidrolisados de Proteína/química , Hidrólise , Zea mays/química , Dipeptidil Peptidase 4 , Tripsina/metabolismo , Inibidores da Enzima Conversora de Angiotensina/química , Peptídeo Hidrolases/metabolismo , Subtilisinas/metabolismo , Peptídeos/farmacologia , Peptídeos/química , Peptidil Dipeptidase A , Angiotensinas
5.
Food Funct ; 13(15): 8179-8203, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35829682

RESUMO

This study aimed to investigate the biological potential of underutilized and low-value corn distillers solubles, containing a unique unexplored blend of heat-treated corn and yeast proteins, from the bioethanol industries, by bioinformatic and biochemical approaches. Protein hydrolysates were produced by applying four commercially accessible proteases, among which alcalase provided the best results in terms of yield, degree of hydrolysis, molecular weight, number of proteins, bioactive peptides, and deactivation against anti-angiotensin I-converting enzyme (ACE) and anti-dipeptidyl peptidase IV (DPP IV). The optimal conditions to produce anti-ACE and anti-DPP IV peptides were using alcalase for 10.82 h and an enzyme : substrate ratio of 7.90 (%w/w), with inhibition values for ACE and DPP IV of 98.76 ± 1.28% and 34.99 ± 1.44%, respectively. Corn (α-zein) and yeast (glyceraldehyde-3-phosphate dehydrogenase) proteins were mainly suitable, upon enzymolysis, for the release of bioactive peptides. The peptides DPANLPWG, FDFFDNIN, WNGPPGVF, and TPPFHLPPP inhibited ACE more effectively as verified with binding energies of -11.3, -11.6, -10.5, and -11.6 kcal mol-1, respectively, as compared to captopril (-6.38 kcal mol-1). Compared with the binding energy of sitagliptin (-8.6 kcal mol-1), WNGPPGVF (-9.6 kcal mol-1), WPLPPFG (-9.8 kcal mol-1), LPPYLPS (-9.7 kcal mol-1), TPPFHLPPP (-10.1 kcal mol-1), and DPANLPWG peptides (-10.1 kcal mol-1) had greater inhibition potential against DPP IV. The peptides impeded ACE and DPP IV majorly via hydrophobic and hydrogen linkage interactions. The key amino acids TYR523, GLU384, and HIS353 were bound to the catalytic sites of ACE and GLN553, GLU206, PHE364, VAL303, and THR304 were bound to the DPP IV enzyme. The PHs can be used as ingredients in the feed or food industries with possible health advantages.


Assuntos
Inibidores da Dipeptidil Peptidase IV , Peptidil Dipeptidase A , Dipeptidil Peptidase 4/química , Inibidores da Dipeptidil Peptidase IV/química , Simulação de Acoplamento Molecular , Peptídeos/química , Peptidil Dipeptidase A/química , Subtilisinas , Zea mays/metabolismo
6.
Environ Sci Pollut Res Int ; 29(36): 53967-53995, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35624378

RESUMO

Fertilizers play an essential role in increasing crop yield, maintaining soil fertility, and provide a steady supply of nutrients for plant requirements. The excessive use of conventional fertilizers can cause environmental problems associated with nutrient loss through volatilization in the atmosphere, leaching to groundwater, surface run-off, and denitrification. To mitigate environmental issues and improve the longevity of fertilizer in soil, controlled release fertilizers (CRFs) have been developed. The application of CRFs can reduce the loss of nutrients, provide higher nutrient use efficiency, and improve soil health simultaneously to achieve the goals of climate-smart agricultural (CSA) practices. The major findings of this review paper are (1) CRFs can prevent direct exposure of fertilizer granule to soil and prevent loss of nutrients such as nitrate and nitrous oxide emissions; (2) CRFs are less affected by the change in environmental parameters, and that can increase longevity in soil compared to conventional fertilizers; and (3) CRFs can maintain required soil nitrogen levels, increase water retention, reduce GHG emissions, lead to optimum pH for plant growth, and increase soil organic matter content. This paper could give good insights into the ongoing development and future perspectives of CRFs for CSA practices.


Assuntos
Agricultura , Fertilizantes , Agricultura/métodos , Preparações de Ação Retardada , Fertilizantes/análise , Nitrogênio/análise , Solo/química
7.
Food Chem ; 388: 133036, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35500330

RESUMO

Plant-based protein concentrate (PC) was extracted from under-utilized corn distillers solubles comprising a distinctive heat-treated blend of corn and yeast proteins. Enzymolysis of PC with alcalase generated protein hydrolysate (PH) containing angiotensin converting enzyme (ACE) inhibitory peptides. A novel kinetic model is developed to elucidate enzymolysis kinetics of PC. The PH of greatest DH (∼25%) revealed maximum ACE inhibition (%). Fractionated PH (<3 kDa) had non-toxic and non-allergenic unique peptides encrypted with anti-ACE fragments. Promising bioactive peptides (PeptideRanker > 0.85) docked with ACE had free energies between -8.40 and -10.60 kcal.mol-1 greater than captopril (-6.34 kcal.mol-1). The yeast-derived RLLPF peptide interacted with all active pockets of ACE (S1, S2, S') via hydrogen-, polar- and hydrophobic-bonds. Docking results suggested that ARG522, VAL518, TRP357, TYR523, GLU384, ALA356, ARG124, HIS387, HIS410, ASN66, and ALA354 of ACE aided in stabilizing complexes with peptides. Thus, PH could be used as antihypertensive ingredient for feed, food, or pharmaceutical industries.


Assuntos
Peptidil Dipeptidase A , Hidrolisados de Proteína , Inibidores da Enzima Conversora de Angiotensina/química , Simulação de Acoplamento Molecular , Peptídeos/química , Peptidil Dipeptidase A/metabolismo , Proteínas de Plantas , Hidrolisados de Proteína/química , Tecnologia , Zea mays/metabolismo
8.
Sci Rep ; 12(1): 5038, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35322147

RESUMO

Developing and applying a novel and sustainable energy crop is essential to reach an efficient and economically feasible technology for bioenergy production. In this study, plant tissue culture, also referred to as in vitro culture, is introduced as one of the most promising and environmentally friendly methods for the sustainable supply of biofuels. The current study investigates the potential of in vitro -grown industrial hemp calli obtained from leaf, root, and stem explants as a new generation of energy crop. For this purpose, the in vitro grown explants were first fully characterized in terms of elemental and chemical composition. Secondly, HTL experiments were designed by Design Expert 11 with a particular focus on biocrude. Finally, the chemical components, functional groups, and petroleum-like hydrocarbons present in the biocrude were identified by PY-GCMS. A 22.61 wt.% biocrude was produced for the sample grown through callogenesis of the leaf (CL). The obtained biocrude for CL consisted of 19.55% acids, 0.42% N compounds, 15.44% ketones, 16.03% aldehydes, 2.21% furans, 20.01% aromatics, 5.2% alcohols, and 19.88% hydrocarbons. To the best of the authors' knowledge, this is the first report that in vitro -grown biomass is hydrothermally liquefied toward biocrude production; the current work paves the way for integrating plant tissue culture and thermochemical processes for the generation of biofuels and value-added chemicals.


Assuntos
Biocombustíveis , Petróleo , Biomassa
9.
Waste Biomass Valorization ; 13(3): 1385-1429, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34548888

RESUMO

Single-atom-thick graphene is a particularly interesting material in basic research and applications owing to its remarkable electronic, mechanical, chemical, thermal, and optical properties. This leads to its potential use in a multitude of applications for improved energy storage (capacitors, batteries, and fuel cells), energy generation, biomedical, sensors or even as an advanced membrane material for separations. This paper provided an overview of research in graphene, in the area of synthesis from various sources specially from biomass, advanced characterization techniques, properties, and application. Finally, some challenges and future perspectives of graphene are also discussed.

10.
ACS Omega ; 6(23): 14875-14886, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34151069

RESUMO

Corn wet distillers' fiber (corn fiber) is a byproduct of the corn-ethanol production process, with high potential as a precursor for activated carbon due to its moderate nitrogen content and availability. However, there has been limited investigation into activated carbons from the corn fiber. In this work, we produce activated carbons from the corn fiber using three procedures, including direct KOH activation, hydrothermal carbonization (HTC) followed by KOH activation, and FeCl3-catalyzed HTC followed by KOH activation. Catalytic HTC with FeCl3 was found to slightly increase the degree of carbonization relative to uncatalyzed HTC while also removing the nitrogen content at increasing concentrations and slightly increasing the porosity. The resulting activated carbon samples are then characterized by thermal gravimetric analysis, Fourier transform infrared spectroscopy, scanning electron microscopy, and nitrogen analysis. The two-step process resulted in activated carbon with substantially higher surface areas than the one-step process (1220 vs 789 m2/g), as well as much higher thermal stability and nitrogen content (up to 1.20%). The results show that the corn fiber has potential for activated carbon production, with the two-step HTC followed by the activation process producing more favorable material properties than direct activation.

11.
Sci Rep ; 11(1): 5387, 2021 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-33686179

RESUMO

Two state-of-the-art electrodes were successfully synthesized and used to assemble both symmetric and asymmetric type supercapacitors. 3DFAB was fabricated by direct pyrolysis of green macroalgae in the presence of NaOH. Possible NaOH activation mechanisms are proposed, which explains the formation of oxygen functional groups through quick penetration of OH- and NaOH into the vacancies. To obtain CoTLM, the tile-like architecture of cobalt oxides was introduced to the 3D interconnected functional algal biochar (3DFAB) by a simple one-pot hydrothermal method under mild conditions. For the symmetric supercapacitors, the maximum specific capacitance of RAB, 3DFAB, and CoTLM were 158, 296, and 445 F g-1 at the current density of 1 A g-1. Regarding cobalt-based asymmetric systems, the maximum capacitance for the 3DFAB//CoTLM was 411 F g-1. This asymmetric supercapacitor device also retained 100.9% of its initial capacitance after 4000 cycles at the current density of 4 A g-1. Unbuffered aqueous electrolyte and the unique morphological structure used in this study might catapult forward commercialization of such advanced energy storage devices.

12.
Sci Rep ; 11(1): 2254, 2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33500445

RESUMO

Influential spreaders are the crucial nodes in a complex network that can act as a controller or a maximizer of a spreading process. For example, we can control the virus propagation in an epidemiological network by controlling the behavior of such influential nodes, and amplify the information propagation in a social network by using them as a maximizer. Many indexing methods have been proposed in the literature to identify the influential spreaders in a network. Nevertheless, we have notice that each individual network holds different connectivity structures that we classify as complete, incomplete, or in-between based on their components and density. These affect the accuracy of existing indexing methods in the identification of the best influential spreaders. Thus, no single indexing strategy is sufficient from all varieties of network connectivity structures. This article proposes a new indexing method Network Global Structure-based Centrality (ngsc) which intelligently combines existing kshell and sum of neighbors' degree methods with knowledge of the network's global structural properties, such as the giant component, average degree, and percolation threshold. The experimental results show that our proposed method yields a better spreading performance of the seed spreaders over a large variety of network connectivity structures, and correlates well with ranking based on an SIR model used as ground truth. It also out-performs contemporary techniques and is competitive with more sophisticated approaches that are computationally cost.

13.
ACS Omega ; 5(44): 28555-28564, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33195906

RESUMO

Experimental investigations on the technical viability of solid oxide fuel cells to replace internal combustion engines in automobiles have increased in recent years. However, the performance and stability of catalysts in the presence of carbon is key for the commercial success of fuel cell reformers. In this paper, finite element method was used to study the effect of coke deposition on heat and mass transfer during the catalytic partial oxidation of ethanol in a packed bed reactor. The properties of Ni/Al2O3 catalyst bed were investigated after being subjected to several hours of carbon buildup. Bed permeability, porosity, and temperature distribution were significantly affected after just 1500 s of reaction time. It was observed that void fraction and permeability became nonuniform across the bed. These two parameters decreased with axial position, and the difference became more pronounced with time. A decrease in bed porosity reduced the bed temperature due to an increase in effective thermal conductivity and ethanol conversion and hydrogen selectivity decreased as a result. Thus, it was concluded that heat transfer becomes a limiting factor in reforming reactions in the presence of carbon. Production distribution before deactivation was also studied, and it was observed that a maximum ethanol conversion of 100% was achieved at 600 °C and a C/O ratio of 1.0. Finally, results from the reactions were compared to that of a different study to validate the reaction mechanism and similar results were found in the literature.

14.
ACS Omega ; 5(25): 15390-15401, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32637813

RESUMO

In this article, supercritical water gasification of biocrude at different conditions was performed and compared to each other. Three scenarios were considered while treating biocrude originating from cattle manure (CM) and corn husk (CH), namely, uncatalyzed feedstock, catalyzed with 10% Ni-0.08% Ru/Al2O3 and finally catalyzed with 10% Ni-0.08% Ru/Al2O3-ZrO2. It was found that 10% Ni-0.08% Ru/Al2O3-ZrO2 has performed significantly better than the other two scenarios over the 5 hour run time with a 193 and 187% higher hydrogen yield compared to the uncatalyzed and 10% Ni-0.08% Ru/Al2O3 catalyzed scenarios, respectively. Compared to CM gasification in the presence of a 10% Ni-0.08% Ru/Al2O3-ZrO2 catalyst, the catalyst got deactivated because of the high phenol and furan content in the corn husk biocrude, therefore hydrogen yield performance fell significantly. It was observed that the carbon gasification efficiency of the biocrude was independent of temperature. In terms of carbon conversion, the equilibrium conditions for the biocrude considered were attained at lower temperature. A mechanistic model based on the Eley-Rideal method was devised and tested against the obtained data. The dissociation of adsorbed oxygenated hydrocarbon is found to be the rate-determining step with an average absolute deviation of 3.55%.

15.
ACS Omega ; 4(1): 1425-1433, 2019 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-30775646

RESUMO

To lock atmospheric CO2 at anthropogenic timescale, fast weathering silicates can be applied to soil to speed up natural CO2 sequestration via enhanced weathering. Agricultural lands offer large area for silicate application, but expected weathering rates as a function of soil and crop type, and potential impacts on the crops, are not well known. This study investigated the role of plants on enhanced weathering of wollastonite (CaSiO3) in soils. Using rooftop pot experiments with leguminous beans (Phaseolus vulgaris L.) and nonleguminous corn (Zea mays L.), CO2 sequestration was inferred from total inorganic carbon (TIC) accumulation in the soil and thermogravimetric analysis, and mineral weathering rate was inferred from alkalinity of soil porewater. Soil amendment with wollastonite promoted enhanced plant growth: beans showed a 177% greater dry biomass weight and corn showed a 59% greater plant height and a 90% greater dry biomass weight. Wollastonite-amended soil cultivated with beans showed a higher TIC accumulation of 0.606 ± 0.086%, as compared to that with corn (0.124 ± 0.053%). This demonstrates that using wollastonite as a soil amendment, along with legume cultivation, not only buffers the soil against acidification (due to microbial nitrogen fixation) but also sequesters carbon dioxide (12.04 kg of CO2/tonne soil/month, 9 times higher than the soil without wollastonite amendment).

16.
Waste Manag ; 80: 274-284, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30455008

RESUMO

This work presents an investigation into the potential use of eggshell as a CO2 sorbent in the calcium looping gasification of biomass to enhance carbon negativity. Calcination reaction was studied in a quartz wool matrix reactor and a thermogravimetric analyser coupled with a Fourier transform infrared spectroscopy. The resulting sorbent was characterised with a scanning electron microscope, colourimeter, inductively coupled plasma optical emission spectroscopy, and nitrogen sorption analyser. The pore structures of the samples are of Type II isotherm. Results show that increasing the calcination temperature enhances decomposition and improves the calcium content and specific surface area of the sorbent. As compared to nitrogen, calcination in a CO2 environment is not effective due to the increased CO2 partial pressure. Samples with low particle size displayed higher carbonation conversion. Increasing the carbonation temperature to an extent enhances the carbonation conversion. The carbonation conversion by the sorbent in multiple calcination-carbonation cycles was also studied. Initial CO2 uptake by the sorbent was highly encouraging. A conversion of 76.41% was realized after the first cycle, but due to sintering and attrition, the conversion reduced with increasing cycle. The sorbent exhibited a low conversion of 18% after the seventh cycle and this corresponds to a decay extent of 76.65%.


Assuntos
Cálcio , Dióxido de Carbono , Animais , Biomassa , Carbonato de Cálcio , Casca de Ovo , Óxidos
17.
Bioresour Technol ; 200: 804-11, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26584229

RESUMO

The effect of the phase during the hydrothermal carbonization (HTC) of corn husks was studied to determine whether liquid water or water vapor was the more suitable reaction medium, as well as if the HTC process could produce a solid fuel (hydrochar) from green corn husks that was comparable to coal. Using liquid water for the HTC process produced a hydrochar with an increased heating value (27.66MJkg(-1)) compared to using water vapor (25.46MJkg(-1)). HTC using liquid water removed 90% of the potassium contained in raw corn husk, whereas the water vapor HTC treatment removed 58%. The liquid water treated hydrochar contained a 29% decrease in ash content compared to the water vapor hydrochar. Using a TGA-FTIR analysis the liquid treated hydrochar demonstrated a more coal-like combustion in terms of mass loss and heat production, compared to the vapor treated hydrochar.


Assuntos
Carbono/química , Gases/química , Vapor , Temperatura , Resíduos , Zea mays/química , Reatores Biológicos , Carvão Vegetal/química , Carvão Mineral , Porosidade
18.
Bioresour Technol ; 192: 185-91, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26038322

RESUMO

Life cycle (LC) of ethanol has been evaluated to determine the environmental and economical viability of ethanol that was derived from biosyngas fermentation process (gasification-biosynthesis). Four scenarios [S1: untreated (raw), S2: treated (torrefied); S3: untreated-chemical looping gasification (CLG), S4: treated-CLG] were considered. The simulated biosyngas composition was used in this evaluation process. The GHG emissions and production cost varied from 1.19 to 1.32 kg-CO2 e/L and 0.78 to 0.90$/L, respectively, which were found to be dependent on the scenarios. The environmental and economical viability was found be improved when untreated feedstock was used instead of treated feedstock. Although the GHG emissions slightly reduced in the case of CLG process, production cost was nominally increased because of the cost incurred by the use of CaO. This study revealed that miscanthus is a promising feedstock for the ethanol industry, even if it is grown on marginal land, which can help abate GHG emissions.


Assuntos
Biocombustíveis/análise , Biocombustíveis/economia , Custos e Análise de Custo/economia , Etanol/química , Efeito Estufa/economia , Poluição do Ar/análise , Poluição do Ar/economia , Dióxido de Carbono/química , Meio Ambiente , Fermentação
19.
Sci Total Environ ; 527-528: 401-12, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25981938

RESUMO

As more municipalities and communities across developed world look towards implementing organic waste management programmes or upgrading existing ones, composting facilities are emerging as a popular choice. However, odour from these facilities continues to be one of the most important concerns in terms of cost & effective mitigation. This paper provides a technological and life cycle assessment of some of the different odour control technologies and treatment methods that can be implemented in organics processing facilities. The technological assessment compared biofilters, packed tower wet scrubbers, fine mist wet scrubbers, activated carbon adsorption, thermal oxidization, oxidization chemicals and masking agents. The technologies/treatment methods were evaluated and compared based on a variety of operational, usage and cost parameters. Based on the technological assessment it was found that, biofilters and packed bed wet scrubbers are the most applicable odour control technologies for use in organics processing faculties. A life cycle assessment was then done to compare the environmental impacts of the packed-bed wet scrubber system, organic (wood-chip media) bio-filter and inorganic (synthetic media) bio-filter systems. Twelve impact categories were assessed; cumulative energy demand (CED), climate change, human toxicity, photochemical oxidant formation, metal depletion, fossil depletion, terrestrial acidification, freshwater eutrophication, marine eutrophication, terrestrial eco-toxicity, freshwater eco-toxicity and marine eco-toxicity. The results showed that for all impact categories the synthetic media biofilter had the highest environmental impact, followed by the wood chip media bio-filter system. The packed-bed system had the lowest environmental impact for all categories.


Assuntos
Poluição do Ar/prevenção & controle , Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental/métodos , Odorantes/análise , Poluição do Ar/análise , Meio Ambiente
20.
Bioresour Technol ; 150: 407-11, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23993286

RESUMO

The life cycle of ethanol derived from sawdust by enzymatic hydrolysis process is evaluated to determine if environmentally preferable and economically viable ethanol can be produced. Two scenarios are considered to estimate net energy consumption, greenhouse gas (GHG) emission and production costs. The estimated net energy consumption, GHG emission and production costs are 12.29-13.37 MJ/L, 0.75-0.92 kg CO2 e/L and about $0.98-$1.04/L, respectively depending on the scenarios of this study. The result confirmed that environmental benefit can be gained with present technologies; however, economic viability remains doubtful unless Feed-in Tariff (FiT) is considered. The production cost of ethanol reduces to $0.5/L, if FiT is considered to be $0.025/MJ. This study indicates that the implementation of FiT program for ethanol industry not only helps Ontario mitigate GHG emissions, but may also attract more investment and create rural employment opportunities.


Assuntos
Etanol/metabolismo , Madeira/metabolismo , Biocombustíveis/análise , Biocombustíveis/economia , Biotecnologia/economia , Dióxido de Carbono/análise , Custos e Análise de Custo , Etanol/economia , Termodinâmica
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