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Biomass, bioproducts, Biomasse, bioproduits, Biotechnology, Biotechnologies, Wastes, Déchets, Energy, Énergie, Environment, Environnement, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Biotechnologie, Biotechnology, Absorption, Absorción, Biosorption, Biosorción, Cinétique, Kinetics, Cinética, Eau douce, Fresh water, Agua dulce, Etude comparative, Comparative study, Estudio comparativo, Lanthane, Lanthanum, Lantano, Microorganisme, Microorganism, Microorganismo, Modélisation, Modeling, Modelización, Paroi cellulaire, Cell wall, Pared celular, Algue, Alga, Cell wall properties, Micro algae, and Modelling

In this study, the adsorption and desorption kinetics of lanthanum (La) on micro algal cells was investigated. The internal transcribed spacer (ITS) and 18S ribosomal RNA gene (rRNA) were used for molecular identification of the species. The algal species were found to have 95-98% identities to Desmodesmus multivariabilis, Scenedesmus acuminutus, Chloroidium saccharophilum and Stichococcus bacillaris. The species were cultured and tested independently. D. multivariabilis was found to be the most efficient at adsorbing lanthanum with a maximum sorption capacity (qmax) of 100mg/g and a high affinity (b) of 4.55 L/g. Desorption of La was also highest in D. multivariabilis with recovery up to 99.63% at initial concentration as high as 100 mg/L. Desorption data fitted best to the modified pseudo second-order with a better correlation coefficient (R2) of ≤0.98 than first order model. The results showed feasibility of lanthanum recovery using algal sorbents, a cost effective method.

Biomass, bioproducts, Biomasse, bioproduits, Biotechnology, Biotechnologies, Wastes, Déchets, Energy, Énergie, Environment, Environnement, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Chitosane, Chitosan, Quitosano, Cinétique, Kinetics, Cinética, Dérivé du chitosane, Chitosan derivatives, Quitosano derivado, Ion, Ions, Ión, Résine, Resins, Resina, Solution aqueuse, Aqueous solution, Solución acuosa, Sorbant, Sorbent, Sorbente, Thermodynamique, Thermodynamics, Termodinámica, Uranium, Uranio, Chitosan derivative, Ferromagnetic sorbent, and Uranyl ion removal

Chitosan was cross-linked using glutaraldehyde in the presence of magnetite. The resin was chemically modified through the reaction with tetraethylenepentamine (TEPA) to produce amine bearing chitosan. The resin showed a higher affinity towards the uptake of UO22 ions from aqueous medium: maximum sorption capacity reached 1.8 mmol g-1 at pH 4 and 25 °C. The nature of interaction of UO22 ions with the resin was identified. Kinetics were carried out at different temperatures and thermodynamic parameters were evaluated. Breakthrough curves for the removal of UO22 were studied at different flow rates, bed heights and after 3 regeneration cycles. Hydrochloric acid (0.5 M) was used for desorbing UO22 from loaded resin: desorption yield as high as 98% was obtained.

Biotechnology, Biotechnologies, Ecology, Ecologie, Energy, Énergie, Environment, Environnement, Pollution, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Pollution, Traitement et pollution des eaux, Water treatment and pollution, Pollution des eaux naturelles, Natural water pollution, Phénomènes biologiques et physicochimiques, Biological and physicochemical phenomena, Pollution du sol et des sédiments, Soil and sediments pollution, Propriétés biologiques et physicochimiques des polluants. Interaction dans le sol, Biological and physicochemical properties of pollutants. Interaction in the soil, Terre, ocean, espace, Earth, ocean, space, Sciences de la terre, Earth sciences, Géologie de l'ingénieur et de l'environnement. Géothermie, Engineering and environment geology. Geothermics, Pollution, géologie de l'environnement, Pollution, environment geology, Composé organique, Organic compounds, Compuesto orgánico, Polluant organique persistant, Persistent organic pollutant, Contaminante organico persistente, Activité microbienne, Microbial activity, Actividad microbiana, Aérobie, Aerobe, Aerobio, Bactérie Gram négatif, Gram negative bacteria, Bacteria Gram negativa, Biodisponibilité, Bioavailability, Biodisponibilidad, Carcinogène, Carcinogen, Carcinógeno, Cinétique, Kinetics, Cinética, Composé aromatique polycyclique, Polycyclic aromatic compound, Compuesto aromático policíclico, Composé hydrophobe, Hydrophobic compound, Compuesto hidrofobo, Devenir polluant, Pollutant behavior, Evolución contaminante, Dissolution, Disolución, Dégradation biologique, Biodegradation, Degradación biológica, Environnement, Environment, Medio ambiente, Hydrocarbure, Hydrocarbon, Hidrocarburo, Mutagène, Mutagen, Mutágeno, Phénanthrène, Phenanthrene, Fenantreno, Pollution, and Polución

Metabolism of a low-solubility substrate is limited by dissolution and availability and can hardly be determined. We developed a numerical model for simultaneously calculating dissolution kinetics of such substrates and their metabolism and microbial growth (Monod kinetics with decay) and tested it with three aerobic phenanthrene (PHE) degraders: Novosphingobium pentaromativorans US6-1, Sphingomonas sp. EPA505, and Sphingobium yanoikuyae B1. PHE was present as microcrystals, providing non-limiting conditions for growth. Total PHE and protein concentration were tracked over 6―12 days. The model was fitted to the test results for the rates of dissolution, metabolism, and growth. The strains showed similar efifciency, with vmax values of 12―18 g dw g―1 d―1, yields of 0.21 g g―1, maximum growth rates of 2.5―3.8 d―1, and decay rates of 0.04―0.05 d―1. Sensitivity analysis with the model shows that (i) retention in crystals or NAPLs or by sequestration competes with biodegradation, (ii) bacterial growth conditions (dissolution flux and resulting chemical activity of substrate) are more relevant for the final state of the system than the initial biomass, and (iii) the desorption flux regulates the turnover in the presence of solid-state, sequestered (aged), or NAPL substrate sources.

Biomass, bioproducts, Biomasse, bioproduits, Biotechnology, Biotechnologies, Wastes, Déchets, Energy, Énergie, Environment, Environnement, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Pollution, Déchets, Wastes, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Biotechnologie, Biotechnology, Agronomie. Sciences du sol et productions vegetales, Agronomy. Soil science and plant productions, Agronomie générale. Phytotechnie, General agronomy. Plant production, Utilisation de déchets et sous-produits agricoles et forestiers. Exploitation de la biomasse, bioconversion, Use of agricultural and forest wastes. Biomass use, bioconversion, Biosorption, Biosorción, Cinétique, Kinetics, Cinética, Déchet agricole, Agricultural waste, Desperdicio agrícola, Déchet industriel, Industrial waste, Desperdicio industrial, Industrie agricole, Agricultural industry, Industria agrícola, Isotherme, Isotherm, Isoterma, Métal lourd, Heavy metal, Metal pesado, Agro industrial waste, and Kinetic study

A novel multi-metal binding biosorbent (MMBB) was developed by combining a group of three from the selective natural lignocellulosic agro-industrial wastes for effectively eliminating lead, cadmium, copper and zinc from aqueous solutions. Four MMBBs with different combinations (MMBB1: tea waste, corncob, sugarcane bagasse; MMBB2: tea waste, corncob and sawdust; MMBB3: tea waste, corncob and apple peel; MMBB4: tea waste, corncob and grape stalk) were evaluated. FTIR analysis for characterizing the MMBB2 explored that the MMBB2 contains more functional groups available for multi-metals binding. Comparing among the MMBBs as well as the single group biosorbents, MMBB2 was the best biosorbent with the maximum biosorption capacities of 41.48, 39.48, 94.00 and 27.23 mg/g for Cd(II), Cu(II), Pb(II) and Zn(II), respectively. After 5 times of desorption with CaCl2, CH3COOH and NaCl as eluent, the MMBB2 still remained excellent biosorptive capacity, so as it could be well regenerated for reuse and possible recovery of metals.

Biochemistry, molecular biology, biophysics, Biochimie, biologie moléculaire, biophysique, Biotechnology, Biotechnologies, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Biotechnologie, Biotechnology, Tobamovirus, Virus, Antibactérien, Antibacterial agent, Antibacteriano, Argent, Silver, Plata, Cinétique, Kinetics, Cinética, Croissance, Growth, Crecimiento, Nanoparticule, Nanoparticle, Nanopartícula, Polypeptide, Polipéptido, Virus mosaïque tabac, Tobacco mosaic virus, Biomimétique, Biomimetics, Growth kinetics, Heterogeneous reaction, Polypeptides, and Silver nanoparticles

We report simple, facile and size-controllable synthesis of uniform Ag nanoparticles with tobacco mosaic virus (TMV) as a biomediator in the absence of external reducing agents. UV-vis and TEM analysis show that Ag nanoparticles with average diameter of 2, 4 and 9 nm were obtained by simply tuning the ratio of TMV/Ag(NH3)2+. The Ag formation in the presence of TMV showed autocatalytic growth followed by coalescence. The as-prepared TMV-mediated Ag nanoparticles show substantially higher catalytic and antibacterial activities than previous results. For the 4-nitrophenol hydrogenation reaction, the rate constants per surface area for 2 and 9 nm Ag nanoparticles were determined to be 0.64 and 1.2 Lm-2 s-1 respectively. Both Kirby-Bauer disk diffusion test and tube culture results demonstrate high antibacterial activity of TMV-mediated Ag particles against Escherichia coli, with minimal inhibition concentration (MIC) of 2.3 and 2.5 ppm for 2 and 9 nm Ag nanoparticles respectively. We expect that our biomediated Ag synthesis approach can be readily extended to other biomaterials and metal nanoparticle systems.

Biotechnology, Biotechnologies, Chemical engineering, Génie chimique, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Genie chimique, Chemical engineering, Hydrodynamique des appareils de contact, Hydrodynamics of contact apparatus, Fluidisation, Fluidization, Systèmes solides-solides, Solid-solid systems, Divers, Miscellaneous, Angle contact, Contact angle, Angulo contacto, Capacimètre, Capacitance meter, Capacimétro, Capacité électrique, Capacitance, Capacitancia, Cinétique, Kinetics, Cinética, Craquage catalytique fluide, Fluid catalytic cracking, Craqueo catalítico fluido, Fluidisation, Fluidization, Fluidización, Hydrodynamique, Hydrodynamics, Hidrodinámica, Lit fluidisé, Fluidized bed, Lecho fluidizado, Modélisation, Modeling, Modelización, Surveillance, Vigilancia, Tension superficielle, Surface tension, Tensión superficial, Viscosité, Viscosity, Viscosidad, Débit fluide, Agglomerate formation, Capacitance sensor, Fluid Coking, and Liquid injection

Uniform distribution of liquid feed on fluidized particles increases the yield of valuable products and improves operability in processes such as Fluid Coking™ and Fluid Catalytic Cracking. Contact between the injected liquid and the bed particles can be greatly affected by the liquid properties and local bed hydrodynamics. In this study, the effect of viscosity, contact angle, surface tension, fluidization velocity and atomization gas flowrate on the distribution of liquid sprayed into a fluidized bed was investigated with a reliable and fast response capacitance meter. This method was also extended to monitor the agglomerate breakup kinetics.

Biotechnology, Biotechnologies, Chemical engineering, Génie chimique, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Genie chimique, Chemical engineering, Systèmes solides-solides, Solid-solid systems, Divers, Miscellaneous, Sécurité, Safety, Cinétique, Kinetics, Cinética, Combustion, Combustión, Dimension particule, Particle size, Dimensión partícula, Distribution dimension particule, Particle size distribution, Distribución dimensión partícula, Déflagration, Deflagration, Deflagración, Explosion, Explosions, Explosión, Mélangeage, Mixing, Mezclado, Particule fine, Fine particle, Partícula fina, Poussière, Dust, Polvo, Risque accidentel, Hazard, Riesgo accidente, Aluminum, Deflagration index, and Polydispersity

This paper reports experimental results elucidating the effect of particle size polydispersity (σD) on the explosion severity of aluminum dust. Five mixtures with a median diameter (D50) of 15 μm and σD values of 0.95,1.17,1.48, 1.87, and 2.51, were systematically prepared by mixing original aluminum samples having narrow size distributions. The explosion severity of each sample was determined in a 36 L dust explosion vessel by measuring the maximum pressure (Pmax), the maximum rate of pressure rise ((dP/dt)max), and the deflagration index (KSt). Interestingly, we found that values of Pmax and KSt revealed an increase in explosion severity as σD increases, where the latter presented a more dramatic effect due to the contribution of fine particles on the combustion kinetics. The effect of dust concentration on the explosion propagation was analyzed comparing the time span to reach (dP/dt)max, (τ), during a dust explosion. τ was obtained from the experimental pressure traces of the original samples and their mixtures. The values of Pmax and KSt were plotted as a function of the median diameter (D50) and the volume- (D4,3) and surface- (D3,2) weighted mean diameter. We observed that D3,2 provided a better description of the average sample size and D50 is inadequately related to the real hazard potential of aluminum dust. Therefore, we suggest that the explosion hazard characterization of these types of materials should be reported in terms of D3.2 and σD.

Biotechnology, Biotechnologies, Chemical engineering, Génie chimique, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Genie chimique, Chemical engineering, Adsorption, Systèmes solides-solides, Solid-solid systems, Divers, Miscellaneous, Adsorption, Adsorción, Antibiotique, Antibiotic, Antibiótico, Capacité adsorption, Adsorption capacity, Capacidad adsorción, Cinétique, Kinetics, Cinética, Complexe superficiel, Surface complex, Complejo superficial, En discontinu, Batchwise, En discontinuo, Interaction électrostatique, Electrostatic interaction, Interacción electrostática, Isotherme adsorption, Adsorption isotherm, Isotermo adsorción, Poudre, Powder, Polvo, Solution aqueuse, Aqueous solution, Solución acuosa, Système binaire, Binary system, Sistema binario, pH, Composed materials, Iron oxide, Mesoporous silica, Minocycline adsorption, Solid-water interface, and Surface complexes

The remotion of the antibiotic minocycline (MC) on mesoporous silica (SiO2) and on the binary system iron(III) oxide-SiO2 (Fe-SiO2) has been studied in batch experiments by performing adsorption isotherms/kinetics under different conditions of pH, KCI concentration and temperature. The adsorption of MC on the studied materials is strongly dependent on pH, increasing as pH decreases. The incorporation of a low concentration of iron (1.03 wt.%, mainly as amorphous Fe2O3) on the SiO2 matrix not only increases the adsorption capacity but also changes the adsorption mechanism. The adsorption of MC on SiO2 strongly decreases as KCl concentration increases but it is not significantly affected by varying the temperature. This is attributed to electrostatic attractions and H-bond formations between dimethylamino, amide, carbonylic and phenolic groups of the antibiotic and the functional groups of silica particles. The adsorption of MC on Fe-SiO2, on the contrary, strongly increases as temperature increases but remains invariable by varying the KCl concentration. This suggests that the formation of inner-sphere complexes between the functional groups of the antibiotic and the active sites of Fe2O3 plays a key role on the adsorption mechanism. The analysis of adsorption thermodynamic parameters is also reported and discussed. The synthesized materials can act as excellent adsorbents for environmental and engineering processes.

Biotechnology, Biotechnologies, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Biotechnologie, Biotechnology, Méthodes. Procédés. Technologies, Methods. Procedures. Technologies, Bioconversions. Hémisynthèses, Bioconversions. Hemisynthesis, Carboxylic ester hydrolases, Enzyme, Enzima, Esterases, Hydrolases, Cinétique, Kinetics, Cinética, Modèle cinétique, Kinetic model, Modelo cinético, Mécanisme, Mechanism, Mecanismo, Optimisation, Optimization, Optimización, Solvant, Solvent, Solvente, Triacylglycerol lipase, Isobutyl propionate, Kinetic models, Novozym® 435, Ping-Pong Bi―Bi mechanism, and Solvent free system (SFS)

Isobutyl propionate is widely used in food and beverage industries as a rum flavor. This work presents the optimization and kinetic aspects of synthesis of isobutyl propionate by esterification of propionic acid with isobutyl alcohol using immobilized lipase Novozym® 435 in a solvent free system (SFS). Process parameters such as reaction time, temperature, enzyme loading, speed of agitation, water concentration and acid to alcohol molar ratio were optimized to achieve maximum conversion. Higher conversion of 92.52% was obtained with the reaction conditions such as: temperature 40 C, enzyme loading 5% w/w, acid to alcohol molar ratio 1:3, time 10h and stirring speed of 300 rpm. The bisubstrate kinetic models of the enzyme catalyzed reactions namely Ordered Bi―Bi, Random Bi―Bi and Ping-Pong Bi―Bi were applied to determine the initial rates and correlated with the experimental findings. Ping-Pong Bi―Bi model with substrate inhibition by both acid and alcohol gives the best fit with parameter values as Vmax = 0.5 Mol/min/g catalyst, KA = 0.631 M, KB = 0.003 M, KiA = 0.0042 M and KiB = 0.1539 M for the concentration ranges of 2.25―10.21 M for propionic acid and 2.55―9.01 M for iso-butanol. The immobilized lipase could be reused for seven times with the % conversion of acid reaching to 83%; signifies that still it can be reused for several more times. SFS is the added benefit to produce such commercially valuable flavor ester.

Biochemistry, molecular biology, biophysics, Biochimie, biologie moléculaire, biophysique, Biotechnology, Biotechnologies, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Biotechnologie, Biotechnology, Chimie, Chemistry, Química, Chlorure de sodium, Sodium chloride, Sodio cloruro, Cinétique, Kinetics, Cinética, Dénaturation, Denaturation, Desnaturalización, Inhibition, Inhibición, Paramètre cinétique, Kinetic parameter, Parámetro cinético, Protéine, Protein, Proteína, Synergie, Synergism, Sinergia, Thermodynamique, Thermodynamics, Termodinámica, Tréhalose, Trehalose, Trehalosa, Biophysical chemistry, Ferricytochrome c, Kinetic parameters, and Protein denaturation

It is known that trehalose and sodium chloride (NaCl) can both effectively inhibit acid-induced protein denaturation, but the thermodynamic and kinetic behaviors of acid-induced protein unfolding synergistically inhibited by trehalose and NaCl are unclear. In this study, the synergistic inhibition effects of trehalose and NaCl on the acid-induced unfolding of ferricytochrome c were studied at pH 2.0. Thermodynamic parameters were firstly derived based on fluorescence spectroscopic data. Then, kinetic behaviors were studied using stopped-flow fluorescence spectroscopy. It was found that the kinetics of the acid-induced protein unfolding transformed from a triphasic process (i.e., fast, intermediate and slow phases) into a biphasic one (i.e., intermediate and slow phases) and then a single slow phase process with increasing either trehalose or NaCl concentration in the mixture. The rate constants for all the unfolding phases change slightly, while the amplitudes for the fast and intermediate phases diminish greatly with increasing the concentration of trehalose or NaCl. This clearly indicates that the mixture of trehalose and NaCl could synergistically inhibit acid-induced protein unfolding by reducing the extent of protein conformational changes, thus inducing a stable molten-globule state at higher concentrations of the agents.

Biomass, bioproducts, Biomasse, bioproduits, Biotechnology, Biotechnologies, Wastes, Déchets, Energy, Énergie, Environment, Environnement, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Biomasse, Biomass, Biomasa, Charbon bitumineux, Bituminous coal, Carbón bituminoso, Cinétique, Kinetics, Cinética, Comportement thermique, Thermal behavior, Comportamiento térmico, Lignocellulose, Lignocellulosics, Lignocelulosa, Modélisation, Modeling, Modelización, Mélange, Mixture, Mezcla, Pyrolyse, Pyrolysis, Pirólisis, Synergie, Synergism, Sinergia, Co-pyrolysis, Coal, Lignocellulosic biomass, and Synergistic effect

Co-thermochemical conversion of lignocellulosic biomass and coal has been investigated as an effective way to reduce the carbon footprint. Successful evaluating on thermal behavior of the co-pyrolysis is prerequisite for predicting performance and optimizing efficiency of this process. In this paper, pyrolysis and kinetics characteristics of three kinds of lignocellulosic biomass model components (cellulose, hemicellulose, and lignin) blended with a kind of Chinese bituminous coal were explored by thermogravimetric analyzer and Kissinger-Akahira-Sunose method. The results indicated that the addition of model compounds had different synergistic effects on thermal behavior of the bituminous coal. The cellulose showed positive synergistic effects on the thermal decomposition of the coal bituminous coal with lower char yield than calculated value. For hemicellulose and lignin, whether positive or negative synergistic was related to the mixed ratio and temperature range. The distribution of the average activation energy values for the mixtures showed nonadditivity performance.

Biomass, bioproducts, Biomasse, bioproduits, Biotechnology, Biotechnologies, Wastes, Déchets, Energy, Énergie, Environment, Environnement, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Biotechnologie, Biotechnology, Applications et implications industrielles. Aspects économiques, Industrial applications and implications. Economical aspects, Energie, Energy, Production de biocombustibles, Biofuel production, Environnement et pollution, Environment and pollution, Traitement biologique des boues résiduaires et des déchets, Biological treatment of sewage sludges and wastes, Angiospermae, Gramineae, Monocotyledones, Spermatophyta, Arundo donax, Biochimie, Biochemistry, Bioquímica, Biogaz, Biogas, Biogás, Cinétique, Kinetics, Cinética, Date de récolte, Harvesting date, Fecha de cosecha, Digestion anaérobie, Anaerobic digestion, Digestión anaerobia, Méthane, Methane, Metano, Plante pérenne, Perennial plant, Planta perenne, Plante énergétique, Energy crop, Planta energética, Rendement, Yield, Rendimiento, Biochemical Methane Potential, Double harvest, and Perennial energy crops

This study aimed to investigate the potential of giant reed for biomethane production by examining the influence of harvest time and frequency on the Biochemical Methane Potential (BMP), the kinetics of biomethane accumulation in batch reactors and the expected methane yield per hectare. The crop was cut at five different times, regrowths from early cuts were harvested in autumn and BMP of each cut was assessed. The highest BMP (392 NL kg VS―1) and the best kinetics of methane production were associated to juvenile traits of the crop. By coupling the early cuts with the corresponding regrowths (double harvest), the dry biomass (from 35 to 40 Mg ha―1) equaled that obtained by a single cut at end of the season (38 Mg ha―1), while the methane yield per hectare (11,585―12,981 Nm3 ha―1) exceeded up to 35% the methane produced with a single harvest at crop maturity (9452 Nm3 ha―1).

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Biotechnology, Biotechnologies, Energy, Énergie, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Energie, Energy, Combustibles, Fuels, Bois. Tourbe. Lignite, Wood. Peat. Brown coal, Bois, Wood, Arbre forestier résineux, Softwood forest tree, Arbol forestal resinoso, Coniferales, Gymnospermae, Spermatophyta, Analyse thermique, Thermal analysis, Análisis térmico, Bois de feu, Fuelwood, Leña para fuego, Chromatographie pyrolytique, Pyrolytic chromatography, Cromatografía pirolítica, Cinétique, Kinetics, Cinética, Lignine, Lignin, Lignina, Microscope platine chauffante, Hot stage microscope, Microscopio platina caliente, Mécanisme réaction, Reaction mechanism, Mecanismo reacción, Produit réaction, Reaction product, Producto reacción, Pseudotsuga menziesii, Pyrolyse éclair, Flash pyrolysis, Pirolisis rápida, Pyrolyse, Pyrolysis, Pirólisis, Réacteur, Reactor, Hot stage, Liquid intermediate, and Wire mesh reactor

The formation of liquid intermediates and the distribution of products were studied under slow and fast pyrolysis conditions. Results indicate that monomers are formed from lignin oligomeric products during secondary reactions, rather than directly from the native lignin. Lignin from Douglas-fir (Pseudotsuga menziesii) wood was extracted using the milled wood enzyme lignin isolation method. Slow pyrolysis using a microscope with hot-stage captured the liquid formation (>150 °C), shrinking, swelling (foaming), and evaporation behavior of lignin intermediates. The activation energy (Ea) for 5―80% conversions was 213 kJ mol-1, and the pre-exponential factor (log A) was 24.34. Fast pyrolysis tests in a wire mesh reactor were conducted (300―650 °C). The formation of the liquid intermediate was visualized with a fast speed camera (250 Hz), showing the existence of three well defined steps: formation of lignin liquid intermediates, foaming and liquid intermediate swelling, and evaporation and droplet shrinking. GC/MS and UV-Fluorescence of the mesh reactor condensate revealed lignin oligomer formation but no mono-phenols were seen. An increase in pyrolytic lignin yield was observed as temperature increased. The molar mass determined by ESI-MS was not affected by pyrolysis temperature. SEM of the char showed a smooth surface with holes, evidence of a liquid intermediate with foaming; bursting from these foams could be responsible for the removal of lignin oligomers. Py-GC/MS studies showed the highest yield of guaiacol compounds at 450―550 °C. .

Biomass, bioproducts, Biomasse, bioproduits, Biotechnology, Biotechnologies, Wastes, Déchets, Energy, Énergie, Environment, Environnement, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Pollution, Traitement et pollution des eaux, Water treatment and pollution, Eaux usées, Wastewaters, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Bactérie, Bacteria, Cinétique, Kinetics, Cinética, Eau usée, Waste water, Agua residual, Epuration eau usée, Waste water purification, Depuración aguas servidas, Lutte antipollution, Pollution control, Lucha anticontaminación, Réacteur, Reactor, Simulation, Simulación, Sucrerie, Sugar works, Dulces, Algue, Alga, Remédiation, Remediation, Remediación, C. vulgaris, P. putida, Polyacrylate polyalcohol, Sugar factory wastewater, and Wastewater treatment

The remediation kinetics of simulated sugar factory wastewater (SFW) using an algal―bacterial culture (ABC) of Chlorella vulgaris in association with Pseudomonas putida in a raceway reactor was found to be enhanced by 89% with the addition of 80 ppm of copolymer Polyacrylate polyalcohol (PAPA). This was achieved by efficient suspension of the ABC throughout the water body maintaining optimum pH and dissolved oxygen that led to rapid COD removal and improved algal biomass production. The suspension of the ABC using the co-polymer PAPA maintained a DO of 8―10 mg l―1 compared to 2-3 mg l―1 when not suspended. As a result, the non-suspended ABC only achieved a 50% reduction in COD after 96 h compared to a 89% COD removal using 80 ppm PAPA suspension. In addition, the algae biomass increased from 0.4 g l―1 d―1 for the non-suspended ABC to 1.1 g l―1 d―1 when suspended using 80 ppm PAPA.

Biotechnology, Biotechnologies, Electronics, Electronique, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Biotechnologie, Biotechnology, Méthodes. Procédés. Technologies, Methods. Procedures. Technologies, Méthodes et appareillages divers, Various methods and equipments, Biodétecteurs. Biocapteurs, Biosensors, Biodétecteur, Biosensor, Biodetector, Cinétique, Kinetics, Cinética, DNA, Détecteur, Detector, Electrode, Electrodes, Electrodo, Glucose, Glucosa, Nanoparticule, Nanoparticle, Nanopartícula, Nickel, Niquel, Transfert électron, Electron transfer, Transferencia electrón, Enzymeless biosensor, Nickel oxide, and Triangular nanoparticles

Herein we describe improved electron transfer properties and catalytic activity of nickel oxide nanoparticles (NiONPs) via the electrochemical deposition on DNA modified glassy carbon electrode (DNA/GCE) surface. NiONPs deposited on the bare and DNA-coated GCE showed different morphologies, electrochemical kinetics and catalytic activities. The atomic force microscopy (AFM) images revealed the formation of triangular NPs on the DNA/GCE that followed the shape produced by the DNA template, while the electrodeposition of NiONPs on the bare GCE surface led to the formation of spherical nanoparticles. Electrochemical impedance spectroscopy (EIS) measurements revealed lower charge-transfer resistance (Rct) of triangular NiONPs compared to spherical NPs. Furthermore, the electrocatalytic activity of triangular NiONPs compared to spherical NPs toward glucose oxidation in alkaline media was significantly improved. The amperometric oxidation of glucose at NiONP-DNA/GCE, yielded a very high sensitivity of 17.32 mA mM-1 cm-2 and an unprecedented detection limit of 17 nM. The enhanced electron transfer properties and electrocatalytic activity of NiONP-DNA/GCE can be attributed to the higher fraction of sharp corners and edges present in the triangular NiONPs compared to the spherical NPs. The developed sensor was successfully applied to the determination of glucose in serum samples.

Biotechnology, Biotechnologies, Chemical engineering, Génie chimique, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Genie chimique, Chemical engineering, Adsorption, Systèmes solides-solides, Solid-solid systems, Divers, Miscellaneous, Adsorption, Adsorción, Aire superficielle, Surface area, Area superficial, Capacité adsorption, Adsorption capacity, Capacidad adsorción, Charbon actif, Activated carbon, Carbón activado, Cinétique, Kinetics, Cinética, Conception, Design, Diseño, Matériau composite, Composite material, Material compuesto, Microscopie électronique balayage, Scanning electron microscopy, Microscopía electrónica barrido, Microscopie électronique transmission, Transmission electron microscopy, Microscopía electrónica transmisión, Milieu poreux, Porous medium, Medio poroso, Modélisation, Modeling, Modelización, Nanomatériau, Nanostructured materials, Nanoparticule, Nanoparticle, Nanopartícula, Optimisation, Optimization, Optimización, Ordre 2, Second order, Orden 2, Plan expérience, Experimental design, Plan experiencia, Polluant, Pollutant, Contaminante, Solution aqueuse, Aqueous solution, Solución acuosa, Ultrason, Ultrasound, Ultrasonido, Alizarin Red S, Gold nanoparticles loaded on activated carbon, and Ultrasound-assisted removal

The present study is developed to investigate Alizarin Red S removal process from aqueous solution which was carried out through the application of ultrasound onto gold nanoparticles loaded on activated carbon (Au-NP-AC). The fully detailed characterization of this nanomaterial using TEM, SEM, XRD, and BET shows its high surface area alongside its porous structure which makes this adsorbent a candidate for the removal of a large amount of pollutants. Central composite design and response surface methodology were applied to evaluate the main effect and interaction among the variables. The experimental equilibrium data efficiency fitted the Langmuir model with a high adsorption capacity, while second-order equation was suitable to explain the kinetics of the adsorption. A small amount of adsorbent (0.015 g) was applied for a successful removal of ARS (RE >95%) in a short time (5 min) and with a high adsorption capacity (123.4 mg g-1).

Biomass, bioproducts, Biomasse, bioproduits, Biotechnology, Biotechnologies, Wastes, Déchets, Energy, Énergie, Environment, Environnement, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Bactérie, Bacteria, Enterobacteriaceae, Azote, Nitrogen, Nitrógeno, Cinétique, Kinetics, Cinética, Composé minéral, Inorganic compound, Compuesto inorgánico, Désazotation, Denitrogenation, Desazotación, EDTA, Fer II, Iron II, Hierro II, Fer III, Iron III, Hierro III, Immobilisation, Immobilization, Inmovilización, Klebsiella, Microsphère, Microsphere, Microsfera, Milieu poreux, Porous medium, Medio poroso, Oxyde d'azote, Nitrogen oxide, Nitrógeno óxido, Porosité, Porosity, Porosidad, Réduction chimique, Chemical reduction, Reducción química, Styrène polymère, Styrene polymer, Estireno polímero, Intraparticle diffusion, Iron-reducing bacteria, Magnetic porous microspheres, and Nitrogen oxides removal

Fe3O4 poly (styrene-glycidyl methacrylate) magnetic porous microspheres (MPPMs) were introduced to immobilize Klebsiella sp. FD-3, an iron-reducing bacterium applied to reduce Fe(III)EDTA. The effects of potential inhibitors (S2-, SO2-3, NO-3, NO-2 and Fe(II)EDTA-NO) on Fe(III)EDTA reduction were investigated. S2- reacted with Fe(III)EDTA as an electron-shuttling compound and enhanced the reduction. But Fe(III)EDTA reduction was inhibited by SO2-3 and Fe(II)EDTA-NO due to their toxic to microorganisms. Low concentrations of NO-3 and NO-2 accelerated Fe(III)EDTA reduction, but high concentrations inhibited the reduction, whether by free or immobilized FD-3. The immobilized FD-3 performed better than freely-suspended style. The substrate mass transfer and diffusion kinetics in the porous microspheres were calculated. The value of Thiele modulus and effectiveness factors showed that the intraparticle diffusion was fairly small and neglected in this carrier. Fe(III)EDTA reduction fitted first-order model at low Fe(III)EDTA concentration, and changed to zero-order model at high concentrations.

Biomass, bioproducts, Biomasse, bioproduits, Biotechnology, Biotechnologies, Wastes, Déchets, Energy, Énergie, Environment, Environnement, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Agronomie. Sciences du sol et productions vegetales, Agronomy. Soil science and plant productions, Agronomie générale. Phytotechnie, General agronomy. Plant production, Utilisation de déchets et sous-produits agricoles et forestiers. Exploitation de la biomasse, bioconversion, Use of agricultural and forest wastes. Biomass use, bioconversion, Biomasse, Biomass, Biomasa, Cinétique, Kinetics, Cinética, Coque (fruit), Husk (fruit), Cáscara (fruto), Noisette, Hazelnut, Avellana, Pyrolyse, Pyrolysis, Pirólisis, Thermogravimétrie, Thermogravimetry, Termogravimetría, and Hazelnut husk

This study aims at investigating physicochemical properties and pyrolysis kinetics of hazelnut husk, an abundant agricultural waste in Turkey. The physicochemical properties were determined by bomb calorimeter, elemental analysis and FT-IR spectroscopy. Physicochemical analysis results showed that hazelnut husk has a high calorimetric value and high volatile matter content. Pyrolysis experiments were carried out in a thermogravimetric analyzer under inert conditions and operated at different heating rates (5, 10, 20 °C/min). Three different kinetic models, the iso-conversional Kissinger―Akahira―Sunose (KAS) and Ozawa―Flynn―Wall (OFW) models and Coats―Redfern method were applied on TGA data of hazelnut husk to calculate the kinetic parameters including activation energy, pre-exponential factor and reaction order. Simulation of hazelnut husk pyrolysis using data obtained from TGA analysis showed good agreement with experimental data. Combining with physicochemical properties, it was concluded that this biomass can become useful source of energy or chemicals.

Biomass, bioproducts, Biomasse, bioproduits, Biotechnology, Biotechnologies, Wastes, Déchets, Energy, Énergie, Environment, Environnement, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Biotechnologie, Biotechnology, Applications et implications industrielles. Aspects économiques, Industrial applications and implications. Economical aspects, Energie, Energy, Production de biocombustibles, Biofuel production, Biocarburant, Biofuel, Biocarburante, Biomasse, Biomass, Biomasa, Chromatographie phase gazeuse, Gas chromatography, Cromatografía fase gaseosa, Chromatographie pyrolytique, Pyrolytic chromatography, Cromatografía pirolítica, Cinétique, Kinetics, Cinética, Energie activation, Activation energy, Energía activación, Microorganisme, Microorganism, Microorganismo, Modélisation, Modeling, Modelización, Méthode couplée, Coupled method, Método acoplado, Pyrolyse, Pyrolysis, Pirólisis, Spectrométrie masse, Mass spectrometry, Espectrometría masa, Algue, Alga, DAEM, Microalgae, and Py―GC/MS

To assess the energy potential of different microalgae, Chlorella sorokiniana and Monoraphidium were selected for studying the pyrolytic behavior at different heating rates with the analytical method of thermogravimetric analysis (TG), distributed activation energy model (DAEM) and pyrolysis―gas chromatography―mass spectrometry (Py―GC/MS). Results presented that Monoraphidium 3s35 showed superiority for pyrolysis at low heating rate. Calculated by DAEM, during the conversion rate range from 0.1 to 0.7, the activation energies of C. sorokiniana 21 were much lower than that of Monoraphidium 3s35. Both C. sorokiniana 21 and Monoraphidium 3s35 can produce certain amount (up to 20.50%) of alkane compounds, with 9-Octadecyne (C18H34) as the primary compound. Short-chain alkanes (C7―C13) with unsaturated carbon can be released in the pyrolysis at 500 °C for both microalgal biomass. It was also observed that the pyrolysis of C. sorokiniana 21 released more alcohol compounds, while Monoraphidium 3s35 produced more saccharides.

Biomass, bioproducts, Biomasse, bioproduits, Biotechnology, Biotechnologies, Wastes, Déchets, Energy, Énergie, Environment, Environnement, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Biomasse, Biomass, Biomasa, Charbon, Coal, Carbón, Cinétique, Kinetics, Cinética, Condition isotherme, Isothermal condition, Condición isoterma, Pyrolyse, Pyrolysis, Pirólisis, Co-pyrolysis, Hard-coking coal, and Weak-coking coal

To investigate the kinetic characteristics of coking coal mixed with biomass during pyrolysis, thermogravimetric (TG) and thermo-balance reactor (TBR) analyses were conducted under non-isothermal and isothermal condition. Yellow poplar as a biomass (B) was mixed with weak coking coal (WC) and hard coking coal (HC), respectively. The calculated activation energies of WC/B blends were higher than those of HC/B blends under non-isothermal and isothermal conditions. The coal/biomass blends show increased reactivity and decreased activation energy with increasing biomass blend ratio, regardless of the coking properties of the coal. The different char structures of the WC/B and HC/B blends were analyzed by BET and SEM.