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1.
Water Sci Technol ; 84(6): 1309-1323, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34559068

RESUMEN

Environmental and economic considerations suggest a more efficient and comprehensive use of biomass for bioenergy production. One of the most attractive technologies is the microbial fuel cell using the catabolic activity of microorganisms to generate electricity from organic matter. The microbial fuel cell (MFC) has operational benefits and higher performance than current technologies for producing energy from organic materials because it converts electricity from the substrate directly (at ambient temperature). However, MFCs are still not suitable for high energy demand due to practical limitations. The overall performance of an MFC depends on the electrode material, the reactor design, the operating parameters, substrates, and microorganisms. Furthermore, the optimization of the parameters will lead to the commercial development of this technology in the near future. The simultaneous effect of the parameters on each other (intensifier or attenuator) has also been investigated. The investigated parameters in this study include temperature, pH, flow rate and hydraulic retention time, mode, external resistance, and initial concentration.


Asunto(s)
Fuentes de Energía Bioeléctrica , Purificación del Agua , Biomasa , Electricidad , Electrodos , Aguas Residuales
2.
Curr Microbiol ; 78(10): 3770-3781, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34487210

RESUMEN

Enhanced biofuel production strategies from microalgae by employing affordable bio-waste usage are fetching significance, nowadays. This study examines the effect of VWE for enhanced biomass from new indigenous microalgal isolates, Asterarcys sp. SPC, Scenedesmus sp. KT-U, Scenedesmus sp. KTWL-A, Coelastrum sp. T-E, and Chlorella sp. TWL-B. The growth of microalgae in VWE-treated growth media showed considerable increase (1.14-2.3 folds) than control medium (without VWE). Further, two effective native microalgae were selected based on growth in VWE treatment, biomass productivity, and TAG accumulation through statistical clustering analysis. Mixotrophic batch cultivation of Scenedesmus sp. KT-U and Asterarcys sp. SPC cultivated using VWE treatment in the optimum concentration had produced significant average increase in BP (1.8 and 1.4 folds, respectively) than control (without VWE). Whereas in the lipid production phase, there was a noticeable increase in lipid yield in VWE-treated cells of lipid phase (231.8 ± 17.9 mg/L and 243.5 ± 25 mg/L) in Scenedesmus sp. KT-U and Asterarcys sp. SPC, respectively, than in control (140.5 ± 28 mg/L and 166.4 ± 23 mg/L) with considerable TAG accumulation. Thus, this study imparts strain selection process of native microalgae based on vegetable waste usage for improved yield of biomass and lipid amenable for cost-effective biodiesel production.


Asunto(s)
Chlorella , Microalgas , Scenedesmus , Biocombustibles , Biomasa , Lípidos , Verduras , Aguas Residuales
3.
Talanta ; 235: 122752, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34517620

RESUMEN

As the production of biofuels increase, there is an urgent need to easily analytically control their production at the plant level as well as to assess the quality of the final products. Especially method capable of determining fatty acid ethyl ester content of 96.5% is crucial for utilization in praxis. In this work, a refractive index method with required sensitivity was developed and validated by means of a standard reference gas chromatography method. Validation with a considerable set of real unique samples obtained at pilot scale was performed for both purposes - process monitoring at high conversions and final product quality control. The results confirmed a favourable degree of accuracy with a relative deviation lower than 3.5% from the reference value given by the gas chromatography. Moreover, application of the method for quality control of fresh and long-term stored samples revealed that the deterioration of final products during storage can be detected. The developed refractive index method is thus suitable for the simple and rapid evaluation of the quality of produced fatty acid ethyl esters and for analytical monitoring of their production process.


Asunto(s)
Ésteres , Ácidos Grasos , Biocombustibles , Cromatografía de Gases , Ésteres/análisis , Control de Calidad
5.
Bioresour Technol ; 341: 125845, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34467892

RESUMEN

An upgraded digital twin of the Anaerobic Digestion Model 1 is proposed to enhance its industrial applicability and range of use. Through the optimization and generalization of kinetic coefficients toward co-digestion reactors simulation and insertion of new equations for the complete biokinetics modeling of H2S, the proposed model can predict more precisely the exiting biogas fractions comprehensive of H2S and O2 without any parametric adjustment. Moreover, it is proposed a new function representing the oxygen-methanogens. The model has been validated through the comparison with other literature models and with experimental data coming both from the literature and from an industrial plant. The comparisons show its flexibility and industrial applicability. Finally, an optimization of the methane content through oxygen rate adjustment is proposed, increasing CH4 content of 4%vol. The mathematical model has been built using Python™, which makes it easily spreadable and usable.


Asunto(s)
Reactores Biológicos , Metano , Anaerobiosis , Biocombustibles , Digestión
6.
Bioresour Technol ; 341: 125850, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34474233

RESUMEN

The frequent occurrence of surfactants in urban wastewaters represents a multifaceted environmental concern. In this investigation, bio-electro-Fenton-microbial fuel cell (BEF-MFC) was developed for the degradation of sodium dodecyl sulphate (SDS) from wastewater. The synthesised cathode catalyst (powdered activated carbon and iron oxide) facilitated the Fenton reaction in the cathodic chamber of the MFC, concurrently generating a maximum power density of 105.67 mW m-2. The overall performance of the BEF-MFC for SDS removal and power generation excelled the control MFC (C-MFC) having carbon black coated cathode under similar operating conditions. Although, the rate of SDS degradation was favourable in acidic pH, under neutral pH, 70.8 ± 6.4% of SDS degradation was achieved in 120 min in BEF-MFC. A comparison of environmental impacts of BEF-MFC with up-flow MFC and electrochemical oxidation using life cycle assessment tool suggests that BEF-MFC can be one of the promising technologies for the tertiary treatment of wastewater.


Asunto(s)
Fuentes de Energía Bioeléctrica , Contaminantes Químicos del Agua , Electricidad , Electrodos , Peróxido de Hidrógeno , Dodecil Sulfato de Sodio , Aguas Residuales , Contaminantes Químicos del Agua/análisis
7.
Bioresour Technol ; 341: 125829, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34474239

RESUMEN

The stability of dry anaerobic digestion (AD) of food waste (FW) as well as the resulting methane gas generation was investigated from the perspective of system dynamics. Various organic loading rates were applied to the system by modifying the water content in the FW feed and solid retention time (SRT). The excessive organic loading due to the accumulation of volatile fatty acids (VFAs) from the feed with 80% water content during the short SRT (15 and 20 d) caused system failure. In contrast, more intermediate materials, such as VFAs, was easily converted into methane at higher water contents. In addition, the biogas production rate of dry AD was effectively predicted based on SRT, soluble chemical oxygen demand, total VFA, total ammonia, and free ammonia using a recurrent neural network-the so-called "black-box" model. This implies the feasibility of applying this data-based black-box model for controlling and optimizing complex biological processes.


Asunto(s)
Biocombustibles , Eliminación de Residuos , Anaerobiosis , Reactores Biológicos , Alimentos , Metano , Redes Neurales de la Computación
8.
Bioresour Technol ; 341: 125834, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34479139

RESUMEN

Orange waste (OW), an abundant and severe globally environmental treat, was used for biobutanol and biohydrogen production emploing acetone-butanol-ethanol (ABE) fermentation through a biorefinery process. The solvent yield from untreated OW was insufficient; thus, the substrate was subjected to hydrothermal pretreatment before hydrolysis. The pretreatment at 140 ℃ for 30 min resulted in the solid with the highest yield of hydrolysis and fermentation. Moreover, the anaerobic digestion of hydrolysis residue produced appreciable amounts of biomethane. However, the pretreatment liquor was not fermentable; thus, it was detoxified by overliming for 24 h at 30 ℃ and then fermented. Overall, this sustainable biorefinery, based on pretreatment without any additional chemical agent, hydrolysis of pretreated solids, detoxification of pretreatment liquor, ABE fermentation, and anaerobic digestion of residues, produced 42.3 g biobutanol, 33.1 g acetone, 13.4 g ethanol, 104.5 L biohydrogen, and 28.3 L biomethane per kg of OW that contained 4560 kJ energy.


Asunto(s)
Biocombustibles , Citrus sinensis , Acetona , Butanoles , Fermentación , Hidrólisis
9.
J Environ Manage ; 299: 113592, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34479149

RESUMEN

Acid-base bifunctional heterogeneous solid catalysts, known as the active site with base-acid properties, exhibited relatively good performance on the transesterification for soybean oil for green fuel production. We investigated the use of niobium and three alkali metal oxides (Li, Na, and K) as MyNbOX (M = Li, Na, K) composite as acid-base catalysts for biodiesel production. MyNbOX catalysts were prepared using a simple solid-state reaction, mixing, and grinding niobium dioxide with alkali metal carbonates calcined at 800 °C in air for 4 h. XRD, BET, FE-SEM, TEM and TPD techniques were employed for catalysts characterization. The highest biodiesel yield (98.08%) was achieved under the transesterification condition of 65 °C, 6 h, 24 methanol/oil molar ratio and 2 wt% of LiNbO3 as the catalyst. The results showed that LiNbO3 could be efficiently reused at least 10 cycles with an insignificant reduction in the biodiesel yield. The physicochemical properties of the biodiesel were further studied and compared with the ASTM and the EN biodiesel specifications. The results showed that the properties of the biodiesel produced complied with the international standard specifications.


Asunto(s)
Biocombustibles , Aceite de Soja , Catálisis , Esterificación , Metanol
10.
J Environ Manage ; 299: 113656, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34482111

RESUMEN

Chicken manure management has grabbed significant attention in Morocco due to the increasing demand on chicken and eggs. Bioconversion of chicken manure to biogas could reduce the chicken manure amount as well as generate clean energy. To evaluate the feasibility of converting chicken manure to biogas in terms of energy gain, the energy balance of the chicken manure for biogas production in the region of Rabat-Salé-Zemmour-Zaïr of Morocco has been investigated. The result showed that there was an energy gain of 1350 MJ for per tonne of dry chicken manure was converted to biogas. The energy gain increased to 3996 MJ/tonne of dry chicken manure when the wheat straw was added to co-digest with chicken manure. With consideration of converting the obtained biogas for electricity generation, there was extra electricity for sale after subtracting the electricity consumed inside the poultry industry. Comparing with co-firing, pyrolysis, and gasification, chicken manure anaerobic digestion was superior in terms of energy gain.


Asunto(s)
Biocombustibles , Estiércol , Anaerobiosis , Animales , Reactores Biológicos , Metano , Marruecos , Aves de Corral
11.
J Environ Manage ; 299: 113597, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34492435

RESUMEN

This review discusses the technical aspects of improving the efficiency of the pyrolysis of lignocellulosic materials to increase the yield of the main products, which are bio-oil, biochar, and syngas. The latest aspects of catalyst development in the biomass pyrolysis process are presented focusing on the various catalyst structures, the physical and chemical performance of the catalysts, and the mode of the catalytic reaction. In bio-oil upgrading, atmospheric catalytic cracking is shown to be more economical than catalytic hydrotreating. Catalysts help in the upgrading process by facilitating several reaction pathways such as polymerization, aromatization, and alkyl condensation. However, the grade of bio-oil must be similar to that of diesel fuel. Hence, the properties of the pyrolysis liquid such as viscosity, kinematic viscosity, density, and boiling point are important and have been highlighted. Switching between types of catalysts has a significant influence on the final product yields and exhibits different levels of durability. Various catalysts have been shown to enhance gas yield at the expense of the yields of bio-oil and biochar that shift the overall purpose of pyrolysis. Therefore, the catalytic activity as a function of temperature, pressure, and catalyst biomass ratio is discussed in detail. These operational parameters are crucial because they determine the overall yield as well as the ratio of the oil, char, and gas products. Although significant progress has been made in catalytic pyrolysis, the economic feasibility of the process and the catalyst cost remain the major obstacles. This review concludes that the catalytic process would be feasible when the fuel selling price is reduced to less than US $ 4 per gallon of gasoline-equivalent, and when the selectivity of catalysts is further enhanced.


Asunto(s)
Biocombustibles , Pirólisis , Biomasa , Calor , Lignina
12.
J Environ Manage ; 299: 113678, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34523543

RESUMEN

This study assessed the anaerobic digestion (AD) of wastes deriving from cosmetics production: sludge from onsite wastewater treatment plant (sWWTP), residues of shampoo/conditioner (RSC) and sludge from mascara production (MS), considered as single substrates and as mixture according to the produced amounts (54 %-wt sWWTP, 31 %-wt RSC, 13 %-wt MS, plus 2 %-wt food waste from the canteen, FW). Total COD (CODT) was 624-1436 g O2/kg VS, while soluble COD was 5-23 %-wt of CODT. AD tests at 35 °C achieved the following biogas yields: 0.10 Nm3/kgvs (70 %-v/v methane) for sWWTP; 0.07 Nm3/kgvs (62 %-v/v methane) for RSC; 0.04 Nm3/kgvs (67 %-v/v methane) for MS. The mixed substrates underwent physico-chemical pre-treatments (thermo-alkaline, TA: 120 min at 50 °C; thermo-alkaline-sonication, TAS: 15 min at 40 kHz and 80 °C, both based on the addition of 0.08 g NaOH per each g of total solid in the substrate), reaching 64-66% disintegration rate, and AD tests (5 %-wt dry substance) at 35 and 52 °C. Biogas yields were (for TA and TAS respectively): 0.22 and 0.20 Nm3/kgVS (62-70% methane); 0.21 and 0.19 Nm3/kgVS (66-66% methane) at 52 °C. At both temperatures, methane yields considerably improved (+71-100%), compared to mixed untreated substrates, and 5-8 %-wt total solids reductions were observed. A technical-economic scale-up assessment completed the research. The energy analysis highlighted the crucial role of TA pre-treatment in achieving the process energetic sustainability. The economic analysis showed that the AD of the considered cosmetic waste could be sustainable anyway, thanks to the savings related to the disposal of the digestate compared to current waste management costs.


Asunto(s)
Cosméticos , Eliminación de Residuos , Anaerobiosis , Biocombustibles , Reactores Biológicos , Estudios de Factibilidad , Alimentos , Residuos Industriales/análisis , Metano , Aguas del Alcantarillado
13.
Bioresour Technol ; 341: 125909, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34523547

RESUMEN

A novel electrochemical system of microbial fuel cell (MFC) coupled solid-phase denitrification biofilm reactor (DBR) system was established to explore the effect of simultaneous power generation and pollutant removal under different HRTs (Ⅰ:48 h; Ⅱ :24 h). The average removal rates of methyl orange, Cr (VI) and NO3--N in test group were 93.0, 98.6 and 95.5% within 60 days, while those were 53.1, 72.1 and 72.7% in control. The maximum power density was 61.2 (Ⅰ) and 16.1 mW/m2 (Ⅱ), while average output voltage was 122 (Ⅰ) and 83.6 mV (Ⅱ). Components 1 and 2 in soluble microbial products were identified, and the humic-like and fulvic acid-like substances varied through different layers. Pseudomonas produced electricity in anode, while denitrified in denitrification layer. Importantly, symbiotic cooperation was absolutely dominant in network analysis of both anodic and denitrifying biofilms. MFC significantly improved DBR's ability to treatment co-polluted wastewater.


Asunto(s)
Fuentes de Energía Bioeléctrica , Contaminantes Ambientales , Microbiota , Desnitrificación , Electricidad , Electrodos , Aguas Residuales
14.
Bioresour Technol ; 341: 125857, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34523553

RESUMEN

Pyrolysis characteristics and bio-oil of Chlorella vulgaris were investigated under SiC and ZnO (SZ) mixture (compound additive) with various mixing ratios (S/Z = 10:0, 7:3, 5:5, 3:7, 0:10) and addition amounts (5%, 10%, 15%) by thermogravimetric analysis and GC-MS. At three experimental groups of 10% compound additive, as ZnO in compound additive increased, maximum weight loss rate (Rp) increased, the time (tp) corresponding to Rp and the weight stabilization time (tf) first decreased and then increased, while average rate of weight loss (Ra) and total weight loss (M) first increased and then decreased; maximum temperature rising rate (Hx) and average rate of temperature rising (Hg) increased, while the time (tx) corresponding to Hx decreased. Compound additives reduced the bio-oil yield, increased the gas yield, and reduced the acid compounds in bio-oil. Besides, it might promote the production of alicyclic hydrocarbons and oxygen/nitrogen-containing long-chain compounds.


Asunto(s)
Chlorella vulgaris , Biocombustibles , Calor , Microondas , Pirólisis , Temperatura
15.
Bioresour Technol ; 341: 125874, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34523567

RESUMEN

To solve the issue of narrow micropores in traditional protonic type Zeolite Socony Mobil-5 (HZSM-5) catalysts in the restricting of large-molecular reactants/products diffusion, hollow HZSM-5 with a mesoporous shell was prepared using a hydrothermal method combined with a tetrapropylammonium hydroxide (TPAOH) treatment process. Applying for in-situ catalyst upgrading of bio-oil from rapid pyrolysis of biomass, the obtained most efficient catalyst of Hollow(30)-TP resulted in aromatic hydrocarbon yields in the range of 78.49-78.67% for cellulose and hemicellulose, which is much greater than those using the traditional HZSM-5 (61.06-68.26%). Furthermore, in the case using real biomass (cedar) with an optimal biomass/catalyst weight ratio of 1:2, the aromatic hydrocarbon yield reached up to 80.16%. In addition, this catalyst exhibited excellent reusability and regeneration property due to the increased accessibility to the acid sites in the hollow HZSM-5 for the improving of the reaction rate as well as the reducing of coking.


Asunto(s)
Biocombustibles , Pirólisis , Biomasa , Catálisis , Calor , Aceites Vegetales , Polifenoles
16.
Bioresour Technol ; 341: 125826, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34523568

RESUMEN

Corn straw (CS) was pretreated by ultrasonic combined aerobic with biogas slurry as medium for anaerobic digestion (AD), that strengthened the degradation efficiency CS, varied in the composition of digestion slurry, thereby the methane production was increased. Central combinatorial design (CCD) test was used to treat CS at ultrasonic power (200, 400, and 600 W), time (10, 20, and 30 min) and AD for 25 days, at 37 ± 1℃. According to data showed that the pH and volatile fatty acids (VFAs) affected methane production directly. With an ultrasonic power 309 W, time 26 min, it reached the maximum content of VFAs with 16.24 g/L, the cumulative methane production achieved the highest with 198.56 mL/g VS, which was 46.73% higher than unpretreated raw material as CK. Ultrasonic-aerobic hydrolysis pretreatment can obtain higher VFAs and methane production content in a short period of time that is great significance to biogas engineering.


Asunto(s)
Metano , Zea mays , Anaerobiosis , Biocombustibles , Hidrólisis , Ultrasonido
17.
Bioresour Technol ; 341: 125877, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34523574

RESUMEN

Energy security and global climate change have necessitated the development of renewable energy with net-zero emissions. As alternatives to traditional fuels used in heavy-duty vehicles, advanced biofuels derived from fatty acids and terpenes have similar properties to current petroleum-based fuels, which makes them compatible with existing storage and transportation infrastructures. The fast development of metabolic engineering and synthetic biology has shown that microorganisms can be engineered to convert renewable feedstocks into these advanced biofuels. The oleaginous yeast Yarrowia lipolytica is rapidly emerging as a valuable chassis for the sustainable production of advanced biofuels derived from fatty acids and terpenes. Here, we provide a summary of the strategies developed in recent years for engineering Y. lipolytica to synthesize advanced biofuels. Finally, efficient biotechnological strategies for the production of these advanced biofuels and perspectives for future research are also discussed.


Asunto(s)
Yarrowia , Biocombustibles , Ácidos Grasos , Ingeniería Metabólica , Biología Sintética , Yarrowia/genética
18.
Bioresour Technol ; 341: 125902, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34523575

RESUMEN

Biohydrogen using migrated ammonia as nitrogen source, and biogas upgrading with hydrogen collected at biocathode in an integrated bioelectrochemical system (BES) were investigated, during the anaerobic digestion of Taihu blue algae. Under an applied voltage of 0.4 V, biohydrogen (202.87 mL) reached 2.34 and 2.90 times than groups with applied voltage of 0 V and 0.8 V, respectively. Moreover, biohydrogen of the group with 1000 mg/L initial ammonia addition (524.16 mL) reached 1.53 times than that the of the control. With 0.25 bar of H2 injected at the beginning (R1), highest methane production (286.62) mL and content (75.73%) were obtained. Comparing to other groups, not only microbial genus responsible for both aceticlastic and hydrogenotrophic methanogens of the group R1 were apparently enriched, but key enzymes related to methane production also acquired better abundances. Therefore, it's promising to conduct the ammonia alleviating, hydrogen producing and biogas upgrading simultaneously using BES.


Asunto(s)
Amoníaco , Biocombustibles , Anaerobiosis , Reactores Biológicos , Hidrógeno , Metano , Nitrógeno
19.
Bioresour Technol ; 341: 125915, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34523582

RESUMEN

Anaerobic digestion (AD) is a widely used technology to valorise food waste for biogas production yet a considerable amount of digestate remains under-utilised. Sustainable management and recycling of the nutrient-rich food waste anaerobic digestate (FWD) is highly desirable for closing resource loop and actualising circular economy. This work reviews the distinct properties of FWD and the existing treatment technologies. FWD shows great prospects as a nutrient source for microalgal cultivation and biofuel production. Emerging technologies such as thermal conversion (e.g., pyrolysis and hydrothermal treatment) of FWD into value-added products such as functionalised biochar/hydrochar with diverse applications would be attractive and warrant further research investigation. Integrated AD with subsequent valorisation facilities is highly encouraged to achieve complete utilisation of resources and reduce carbon emissions.


Asunto(s)
Microalgas , Eliminación de Residuos , Administración de Residuos , Anaerobiosis , Biocombustibles , Alimentos
20.
Environ Sci Pollut Res Int ; 28(38): 52832-52843, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34476693

RESUMEN

Rising human population has increased the utilization of available resources for food, clothes, medicine, and living space, thus menacing natural environment and mounting the gap between available resources, and the skills to meet human desires is necessary. Humans are satisfying their desires by depleting available natural resources. Therefore, multifunctional plants can contribute towards the livelihoods of people, to execute their life requirements without degrading natural resources. Thus, research on multipurpose industrial crops should be of high interest among scientists. Hemp, or industrial hemp, is gaining research interest because of its fastest growth and utilization in commercial products including textile, paper, medicine, food, animal feed, paint, biofuel, biodegradable plastic, and construction material. High biomass production and ability to grow under versatile conditions make hemp, a good candidate species for remediation of polluted soils also. Present review highlights the morphology, adaptability, nutritional constituents, textile use, and medicinal significance of industrial hemp. Moreover, its usage in environmental conservation, building material, and biofuel production has also been discussed.


Asunto(s)
Cannabis , Alérgenos , Animales , Biocombustibles , Biomasa , Humanos , Industrias
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