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1.
Chem Commun (Camb) ; 60(68): 9074-9077, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39104310

RESUMEN

This study presents a self-bonding conductive electrode triggered by water-induced structure reconfiguration. Water wetting causes the swelling and mobility of cotton-derived cellulose nanofibers in the conductive electrode, and the formation of hydrogen bonds, which enables the conductive electrode to heal damage, bond separated pieces, and directly bond on diverse substrates.

2.
RSC Adv ; 11(30): 18213-18224, 2021 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-35480937

RESUMEN

This study attempts to enhance the mixture instability of methanol/hydrous methanol mixed with diesel fuel, waste cooking oil (WCO) biodiesel, and Jet A-1 fuel using n-octanol and n-decanol as cosolvent at numerous temperatures of 10 °C, 20 °C, and 30 °C. The experiment is divided into two stages: first, blending pure methanol with diesel oil, Jet A-1, and WCO biodiesel individually utilizing n-octanol and n-decanol as cosolvent at various temperatures. Second, combining hydrous methanol (90% methanol + 10 wt% water) with diesel oil, Jet A-1, and WCO biodiesel independently and applying n-octanol and n-decanol as cosolvent at different temperatures. Pure methanol or hydrous methanol is mixed with the base fuels at different mixing proportions varying from 0 to 100 vol% with 10 vol% increments. The co-solvent, mainly n-octanol and n-decanol (titrant), is progressively and separately inserted into the tube with continuous shaking by utilizing a high-precision pipette until the ternary mixtures' phase borders seem. The findings demonstrate phase separation in pure methanol-diesel and pure methanol-Jet A-1 combinations even when the blend temperature increased to 60 °C. The pure methanol/biodiesel combination proves complete solubility without adding an external agent. The results also illustrate that the ambient temperature considerably affects the stability of mixture and amount of cosolvent in the blend. n-Octanol and n-decanol showed promising performance in enhancing the phase stability issue of methanol and hydrous methanol with the base fuels. It can be deduced that the minimum amount of cosolvent is recorded for biodiesel-hydrous methanol, Jet A-1-hydrous methanol, and diesel-hydrous methanol, respectively.

3.
J Hazard Mater ; 379: 120810, 2019 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-31255849

RESUMEN

In this study, the alkaline hydrothermal ferric carbon (AHFC), which was prepared by hydrothermal liquefaction method using Fenton iron sludge with NH3·H2O, was used as a skeleton materials for the dewatering of sewage sludge (SS) via thermal hydrolysis. NH2 functional group presented in the AHFC and nano-sized γ-Fe2O3 was anchored on the surface of AHFC. The NH2 functional group notably promoted thermal hydrolysis of SS from the increasing of TOC and TN value. γ-Fe2O3 showed adsorption effect to the water, resulting in decline of the dewatering rate of SS in present condition. When 100% of AHFC was added, dewatering rate of SS was decreased by 19.93% (at 160 °C), 4.50% (at 180 °C) and 8.34% (at 200 °C) respectively. 3D-EEM results showed that the degree of hydrolysis was deepened when AHFC was added for the intensity of soluble microbial products decline. AHFC promoted the decomposition of protein to form heterocycle compounds in the resulting cake according to in situ FTIR results. The nano γ-Fe2O3 catalysis to cake also can be observed for the activation energy was lower than blank in the range of 40˜60%. The study demonstrated concept and the effectiveness the reuse/recycle of the Fenton iron sludge for dewatering of SS.


Asunto(s)
Amoníaco/química , Desecación/métodos , Peróxido de Hidrógeno/química , Hierro/química , Aguas del Alcantarillado/química , Eliminación de Residuos Líquidos/métodos , Calor , Hidrólisis
4.
Bioresour Technol ; 278: 311-317, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30711839

RESUMEN

In order to obtain the N-containing organics from cellulose under mild conditions, hydrothermal liquefaction of cellulose in the presence of ammonia was conducted in this study. The results showed that the increasing reaction temperature and prolonging time facilitated the conversion of cellulose in hydrothermal liquefaction (HTL) with NH3·H2O and decreased the amount of solid residue. Reaction temperature showed more influence than reaction time on solid residue formation. The components of bio-oil were significantly affected by reaction temperature and reaction time. Electrospray ionization-Fourier transform-ion cyclotron resonance-mass spectrometry (ESI FT-ICR MS) provided an insight for understanding the distribution of the different kinds of N-heterocycle compounds in the bio-oil. The possible reaction pathway of N-heterocycle compounds formation from cellulose during hydrothermal liquefaction with NH3·H2O was proposed.


Asunto(s)
Celulosa/química , Amoníaco/química , Espectrometría de Masas , Temperatura , Agua/química
5.
Bioresour Technol ; 270: 129-137, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30216922

RESUMEN

Hydrothermal liquefaction (HTL) of microalgae produces high amount of water-insoluble organic compounds, the biocrude oil. Using high-growth-rate Spirulina platensis as feedstock, product fraction distribution and biocrude oil chemistry from HTL at a temperature of 240-300 °C under acidic, neutral and alkaline condition were studied. Positive effects on biocrude oil yield were only found with KOH and acetic acid, and these effects were stronger under milder HTL conditions. FT-ICR MS showed that O2 class in the biocrude was high due to higher carbohydrate in the biomass, numbers of N3O5-6 species present in the sample from acetic acid run, indicating its less decarboxylation ability. GC-MS showed more ketones and amides were formed from fatty acids in catalytic HTL, and this effect was sensitive toward reaction temperature. GPC suggested more light volatiles were in biocrude from KOH run, while analysis from NMR, FT-IR and elemental confirmed its high oil quality.


Asunto(s)
Cianobacterias/química , Microalgas/química , Biomasa , Catálisis , Cromatografía de Gases y Espectrometría de Masas , Concentración de Iones de Hidrógeno , Petróleo , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura
6.
Bioresour Technol ; 256: 446-455, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29477083

RESUMEN

The green macroalga Enteromorpha clathrata was pyrolyzed with or without catalysts at the temperature of 550 °C for producing high-quality bio-oil. The ZSM-5 and 1,2,3 mmol Mg-Ce/ZSM-5 catalysts were introduced to investigate the yields and components distribution of bio-oil. Increase of bio-oil production was obtained with the use of ZSM-5 and 1,2,3 mmol Mg-Ce/ZSM-5 catalysts. The 1 mmol Mg-Ce/ZSM-5 catalyst exhibited more promising property for promoting the relative content of C5-C7 compounds, and decreasing the relative content of acids in bio-oil. The results suggested that E. clathrata had potential as pyrolysis feedstocks for producing the high-quality bio-oil with large amounts of C5-C7 compounds and low relative content of acids when the 1 mmol Mg-Ce/ZSM-5 catalyst was used. Furthermore, the physicochemical properties of ZSM-5 and 1 mmol Mg-Ce/ZSM-5 catalysts were investigated by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and temperature-programmed desorption of ammonia.


Asunto(s)
Metales , Aceites de Plantas , Biocombustibles , Catálisis , Polifenoles , Algas Marinas
7.
Bioresour Technol ; 249: 992-999, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29145127

RESUMEN

In the present work, a novel approach of using growth medium with different substitutions of lipid-free algal hydrolysate (LFAH, 0, 5, 10 and 15%) and/or waste glycerol (WG, 0, 5, 10 and 20 g L-1) for enhanced biodiesel production from Scenedesmus obliquus was studied. Combination of different concentrations of WG with 15% LFAH showed the maximum significant biomass productivity, which represented 27.4, 30.5 and 28.9% over the control at combined 5, 10 and 20 g L-1 WG, respectively. The combinations of different LFAH with 20 g L-1 WG showed the maximum significant lipid accumulation, where lipid productivity showed its maximum significant value of 59.66 mg L-1 d-1 using LFAH15-WG10. In addition, LFAH15-WG10 significantly enhanced total FAMEs yield by 21.2% over the control. Moreover, it reduced polyunsaturated fatty acids (PUFAs) ratio from 52.1% to 47.8% of total FAMEs, and increased monounsaturated fatty acids (MUFAs) ratio from 26.6% to 31.3% of total FAMEs.


Asunto(s)
Microalgas , Biocombustibles , Biomasa , Glicerol , Lípidos , Scenedesmus
8.
Entropy (Basel) ; 20(11)2018 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-33266542

RESUMEN

Mixture working fluids can reduce effectively energy loss at heat sources and heat sinks, and therefore enhance the organic Rankine cycle (ORC) performance. The entropy and entransy dissipation analyses of a basic ORC system to recover low-grade waste heat using three mixture working fluids (R245fa/R227ea, R245fa/R152a and R245fa/pentane) have been investigated in this study. The basic ORC includes four components: an expander, a condenser, a pump and an evaporator. The heat source temperature is 120 °C while the condenser temperature is 20 °C. The effects of four operating parameters (evaporator outlet temperature, condenser temperature, pinch point temperature difference, degree of superheat), as well as the mass fraction, on entransy dissipation and entropy generation were examined. Results demonstrated that the entransy dissipation is insensitive to the mass fraction of R245fa. The entropy generation distributions at the evaporator for R245/pentane, R245fa/R152a and R245fa/R227ea are in ranges of 66-74%, 68-80% and 66-75%, respectively, with the corresponding entropy generation at the condenser ranges of 13-21%, 4-17% and 11-21%, respectively, while those at the expander for R245/pentane, R245fa/R152a and R245fa/R227ea are approaching 13%, 15% and 14%, respectively. The optimal mass fraction of R245fa for the minimum entropy generation is 0.6 using R245fa/R152a.

9.
Bioresour Technol ; 228: 305-314, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28086171

RESUMEN

Co-pyrolysis conversion of seaweed (Enteromorpha clathrat and Sargassum fusiforme) polysaccharides and cellulose has been investigated. From the Py-GC/MS results, Enteromorpha clathrata (EN) polysaccharides pyrolysis mainly forms furans; while the products of Sargassum fusiforme (SA) polysaccharides pyrolysis are mainly acid esters. The formation mechanisms of H2O, CO2, and SO2 during the pyrolysis of seaweed polysaccharides were analyzed using the thermogravimetric-mass spectrometry. Meanwhile the pyrolysis of seaweed polysaccharide based on the Amber and the ReaxFF force fields, has also been proposed and simulated respectively. The simulation results coincided with the experimental results. During the fast pyrolysis, strong synergistic effects among cellulose and seaweed polysaccharide molecules have been simulated. By comparing the experimental and simulation value, it has been found that co-pyrolysis could increase the number of molecular fragments, increase the pyrolysis conversion rate, and increase gas production rate at the middle temperature range.


Asunto(s)
Biotecnología/métodos , Celulosa/química , Simulación por Computador , Algas Marinas/química , Temperatura , Cromatografía de Gases y Espectrometría de Masas , Gases/análisis , Modelos Moleculares , Sargassum/química , Termogravimetría
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