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1.
Food Chem ; 369: 130963, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34479005

RESUMEN

Oleogels,gels in which the continuous liquid phase is oil, have been suggested as promising low-saturated alternatives to the conventional shortenings. In this study, we aimed to develop and optimize low saturated oleogel shortenings using ethylcellulose or ethylcellulose/hydroxypropyl methylcellulose biopolymers (as oleogelators), sunflower oil (as the base oil), and palm stearin (as the source of saturated fatty acids). Using the response surface-d-optimal method, oleogel formulations containing saturated fatty acids as low as 15.19 % could be developed. As compared to the commercial shortening samples, oleogel shortenings had much lower saturation levels (15.19-17.02 vs 47.87-58.65 %) but a comparable melting point, firmness, and rheological properties. However, oleogel samples had lower solid fat content and induction period of oxidation than commercial ones. Oleogel made using ethylcellulose/hydroxypropyl methylcellulose biopolymers contained lower saturation level, solid fat content, induction period of oxidation, and firmness but a higher melting point, as compared to that made using ethylcellulose.


Asunto(s)
Metilcelulosa , Biopolímeros , Celulosa/análogos & derivados , Derivados de la Hipromelosa , Compuestos Orgánicos
2.
J Hazard Mater ; 421: 126657, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34315023

RESUMEN

The study aims to prepare a novel low-cost and environmentally friendly adsorbent by using date pits (DP) impregnated with cellulose nanocrystals (CNCs) and ionic liquid (IL), named IL-CNC@DP. The batch adsorption of lithium onto IL-CNC@DP and DP were studied at different pH values, initial lithium concentrations, and temperatures. The thermodynamics constants of the adsorption process showed that the IL-CNC@DP was exothermic, did not favor a high level of disorder, and spontaneous in nature. At pH 6, there is a significant increase in the removal efficiency where it increased to 90%. This also could be explained by the fact that electrostatic attraction forces and hydrogen bonding existed between the protonated Li+ and the less protonated IL-CNC@DP adsorbent surface, which enhanced the percentage of Li+ removal. A strong inter- and intra-hydrogen bonding (O-H) stretching absorption is seen at 3311 cm-1 that occurs in cellulose components. In conclusion, the IL-CNC@DP in comparison to the DP confirmed exceptional results proving that the modification enhanced the remediation of the Li+ from water. Furthermore, the selectivity of IL-CNC@DP towards real groundwater samples isolated in Qatar depends upon the physicochemical characteristics of each element.


Asunto(s)
Agua Subterránea , Líquidos Iónicos , Nanopartículas , Adsorción , Celulosa , Iones , Litio
3.
J Colloid Interface Sci ; 605: 193-203, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34325341

RESUMEN

High-performance electromagnetic (EM) wave absorption and shielding materials integrating with flexibility, air permeability, and anti-fatigue characteristics are of great potential in portable and wearable electronics. These materials usually prepared by depositing metal or alloy coatings on fabrics. However, the shortcomings of heavy weight and easy corrosion hamper its application. In this work, the cellulose nanofiber (CF) fabric was prepared by electrospinning technology. Then, conductive polyaniline (PANI) was deposited on the CF surface via a facile in-situ polymerization process. The interweaving cellulose/polyaniline nanofiber (CPF) composite constructs a conductive network, and the electrical conductivity can be adjusted by polymerization time. Benefiting from optimal impedance matching, strong conductive loss, as well as interfacial polarization, the CPF possesses excellent EM absorption performance. The minimum reflection loss (RLmin) value is -49.24 dB, and the effective absorption bandwidth (RL < -10 dB, fe) reaches 6.90 GHz. Furthermore, the CPF also exhibits outstanding electromagnetic interference (EMI) shielding capability with shielding efficiency (SE) of 34.93 dB in the whole X band. Most importantly, the lightweight CPF fabrics have the merits of mechanical flexibility, breathability and wash resistance, which is highly applicable for wearable devices.


Asunto(s)
Celulosa , Microondas , Compuestos de Anilina , Textiles
4.
J Environ Manage ; 301: 113850, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34619590

RESUMEN

Chitosan is a natural fiber, chemically cellulose-like biopolymer, which is processed from chitin. Its use as a natural polymer is getting more attention because it is non-toxic, renewable, and biocompatible. However, its poor mechanical and thermal strength, particle size, and surface area restrict its industrial use. Consequently, to improve these properties, cellulose and/or inorganic nanoparticles have been used. This review discusses the recent progress of chitosan and cellulose composite materials, their preparation, and their applications in different industrial sectors. It also discusses the modification of chitosan and cellulose composite materials to allow their use on a large scale. Finally, the recent development of chitosan composite materials for drug delivery, food packaging, protective coatings, and wastewater treatment are discussed. The challenges and perspectives for future research are also considered. This review suggests that chitosan and cellulose nano-composite are promising, low-cost products for environmental remediation involving a simple production process.


Asunto(s)
Quitosano , Nanocompuestos , Purificación del Agua , Materiales Biocompatibles , Celulosa , Quitina
5.
Chemosphere ; 287(Pt 2): 132084, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34500331

RESUMEN

Areca nut husk fibers are easily available and they are abundant agricultural waste, whose utilization to high value products needs more attention. The present study aims at the extraction of cellulose nanocrystals (CNCs) from areca nut husk fibers and the evaluation of its reinforcement capacity in polyvinyl alcohol (PVA) and chitosan (CS) film. The CNC showed rod-like structures, which were confirmed by TEM and AFM analysis. The diameter of the isolated CNC was 19 ± 3.3 nm; the length was about 195 ± 24 nm with an aspect ratio of 10.2 ± 6.8. The zeta potential of CNC was -15.3 ± 1.2 mV. Fourier Transform Infrared Spectroscopy analysis showed that the non-cellulosic compounds were effectively eliminated, and the X-ray diffraction results showed that CNC had higher crystallinity than the raw, alkali, and the bleached fibers. Thermogravimetric analysis revealed good thermal stability for the CNC. Moreover, the effects of the incorporation of CNC on the optical and tensile behaviours of the bionanocomposite film were investigated. The bionanocomposite film retained the same transparency as the PVA/CS film, indicating that the CNC was disseminated evenly in the film. The incorporation of CNC (3 wt%) to the PVA/CS film enhanced the tensile strength of the bionanocomposite film (9.46 ± 1.6 MPa) when compared to the control films (7.81 ± 1.4 MPa). Furthermore, the prepared nanobiocomposite film exhibited good antimicrobial activity against foodborne pathogenic bacteria and postharvest pathogenic fungi. These findings suggest that the bionanocomposite film might be suitable for food packaging applications.


Asunto(s)
Nanocompuestos , Nanopartículas , Areca , Celulosa , Vapor
6.
Chemosphere ; 287(Pt 2): 132108, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34509022

RESUMEN

The groundbreaking innovation and industrialization are ushering in a new era where technology development is integrated with the sustainability of materials. Over the decade, nanocrystalline cellulose (NCC) obtained from lignocellulosic biomass had created a great value in various aspects. The abundantly available empty fruit bunch (EFB) in the palm oil industry has motivated us to utilize it as a sustainable alternative for the isolation of NCC, which is a worthwhile opportunity to the waste management of EFB. Taking advantage of the shape anisotropy and amphiphilic character, NCC has been demonstrated as a natural stabilizer for oil-in-water emulsion. In this work, preparation of highly stable Pickering nanoemulsion using black cumin seed oil and NCC was attempted. Black cumin seed oil is a class of plant oil with various nutritional and pharmaceutical benefits. However, its poor solubility could substantially lower the therapeutic effect, and thus, requires a delivery system to overcome this limitation. The role of NCC in the formation of stable Pickering nanoemulsion was investigated. The emulsification process was found crucial to the resulting droplet size, whereas NCC contributed critically to its stabilization. The droplet size obtained from ultrasonication and microfluidization was approximately 400 nm, as examined using transmission electron microscopy. The droplet (oil-to-water = 2:8) has long-term stability against creaming and coalescence for more than six months. The nanoemulsion stabilized by NCC could allow a better absorption by the human body, thereby maximizing the potential of black cumin seed oil in the personal care and food industries.


Asunto(s)
Celulosa , Frutas , Antioxidantes , Emulsiones , Humanos , Aceite de Palma , Aceites Vegetales
7.
Chemosphere ; 287(Pt 3): 132287, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34563775

RESUMEN

A scalable synthetic procedure for fabricating photoactive carbon dots (CD) from microcrystalline cellulose (MCC) is presented. The MCC was transformed into a photoactive nanosized CD by a one-step acid-assisted thermal-carbonization (~90 °C for 30 min). The efficiency of the obtained CD was determined by photo-removal of toxic hexavalent chromium (Cr(VI)) ions from wastewater. CD obtained from cellulose completely removed 20 ppm of Cr(VI) wastewater within ∼120 min under sunlight illumination. No Cr(VI) removal was observed in dark conditions and with control cellulose material as reference samples. The Cr(VI) removal follows pseudo-first-order kinetics along with a half-life of ∼26 min. Furthermore, the Cr(VI) removal from wastewater was supported via cyclic voltammetry analysis. Using a low-cost, naturally available cellulose material and sulfuric acid, the world's most-used chemical, creates techno-economic prerequisites for a scalable process of photoactive carbon dots.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Carbono , Celulosa , Cromo/análisis , Concentración de Iones de Hidrógeno , Cinética , Luz Solar , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
8.
Environ Pollut ; 292(Pt A): 118283, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34619177

RESUMEN

A passive sampler in the soil environment is a relatively novel technique and has had quite limited applications, especially for pesticides. Oleic acid-embedded cellulose acetate membranes (OECAMs) were developed to evaluate the bioavailability of epoxiconazole (EPO) to earthworms (Eisenia fetida). The uptake of EPO by OECAMs (R2 = 0.975) and earthworms (R2 = 0.938) was compared and found to follow a two-compartment kinetic model. EPO sampling by OECAMs reached equilibrium (94%) within 2 d. OECAM could be used to determine the concentration of EPO in soil porewater. Furthermore, a significant linear relationship (R2 = 0.990) was observed between the EPO concentrations in earthworms and the OECAMs. The EPO concentrations in the porewater and OECAMs were lower in soils with a higher organic matter (OM) content. The EPO concentrations in the porewater, earthworms, and OECAMs decreased by 64.4, 49.0, and 56.1%, respectively, in the presence of 0.5% biochar, compared with the control. Furthermore, the use of OECAMs versus earthworms for soil testing also allows you to avoid factors that increase variance in organisms, such as avoidance behaviors or feeding. Therefore, OECAMs show good potential for use as a passive sampler to evaluate the bioavailability of EPO.


Asunto(s)
Oligoquetos , Contaminantes del Suelo , Animales , Disponibilidad Biológica , Celulosa/análogos & derivados , Compuestos Epoxi , Ácido Oléico , Suelo , Contaminantes del Suelo/análisis , Triazoles
9.
J Colloid Interface Sci ; 607(Pt 1): 134-144, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34500414

RESUMEN

HYPOTHESIS: The synthesis and characterization of aminated nanocrystalline cellulose (ANCC), a new member of the hairy nanocellulose family, is reported. Hairy nanocelluloses consist of a crystalline rod-like body with amorphous cellulose chains ("hairs") at both ends, on which various functional groups can be accommodated. In ANCC these groups are reactive primary amine groups, which are useful for bioconjugation- and Schiff base-centered modifications. We hypothesize that a two-step oxidation-reductive amination of cellulose fibers followed by hydrothermal treatment will result in the formation of rod-like hairy ANCC. EXPERIMENTS: ANCC was prepared by converting the aldehyde groups in cellulose, introduced by a periodate oxidation, to primary amines using ammonia and sodium borohydride, followed by a hot water treatment, during which diamine modified cellulose fibers were converted to ANCC. ANCC was characterized by AFM, TEM, DLS, ELS, FTIR, NMR, XPS and conductometric titration. Antibacterial activity of ANCC was assessed by the viable cell counting method. FINDINGS: ANCC, with an amine content of 5.5 mmol g-1 is a bare nanocolloid (i.e. non-coated, without adsorbed polyelectrolytes or surfactants) which, as far as we know, has a positive charge density larger than any other bare cationic nanocolloid. It was observed that ANCC particles have a needle-like morphology with a width of ~ 5 nm and a length ~ 120 nm. DLS results proof that ANCC is hairy. Spectroscopic analysis confirmed the introduction of surface primary amine groups. ANCC showed promising bactericidal activities, against Gram-negative species due to their thinner and penetrable cell wall.


Asunto(s)
Celulosa , Tensoactivos , Aminación , Cationes , Oxidación-Reducción
10.
Chemosphere ; 286(Pt 2): 131731, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34388866

RESUMEN

Photocatalysis has gained attention as a viable wastewater remediation technique. However, the difficulty of recovering powder-based photocatalyst has often become a major limitation for their on-site practical application. Herein, we report on the successful in-situ preparation of a novel three-dimensional (3D) photocatalyst consisting of Cu2O/TiO2 loaded on a cellulose nanofiber (CNF)/reduced graphene hydrogel (rGH) via facile hydrothermal treatment and freeze-drying. The 3D macrostructure not only provides a template for the anchoring of Cu2O and TiO2 but also provides an efficient electron transport pathway for enhanced photocatalytic activity. The results showed that the Cu2O and TiO2 were uniformly loaded onto the aerogel framework resulting in the composites with large surface area with exposed actives sites. As compared to bare rGH, CNF/rGH, Cu2O/CNF/rGH and TiO2/CNF/rGH, the Cu2O/TiO2/CNF/rGH showed improved photocatalytic activity for methyl orange (MO) degradation. MO degradation pathway is proposed based on GC-MS analysis. The enhanced photoactivity can be attributed to the charge transfer and electron-hole separation from the synergistic effect of Cu2O/TiO2 anchored on CNF/rGH. In terms of their anti-bacterial activity towards Staphylococcus aureus and Escherichia coli, the synergistic effect of the Cu2O/TiO2 anchored on the CNF/rGH framework showed excellent activity towards the bacteria.


Asunto(s)
Grafito , Nanofibras , Antibacterianos/farmacología , Catálisis , Celulosa , Hidrogeles , Titanio
11.
Chemosphere ; 286(Pt 3): 131891, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34416587

RESUMEN

Nanocellulose based gas barrier materials have become an increasingly important subject, since it is a widespread environmentally friendly natural polymer. Previous studies have shown that super-high gas barrier can be achieved with pure and hierarchical nanocellulose films fabricated through simple suspension or layer-by-layer technique either by itself or incorporating with other polymers or nanoparticles. Improved gas barrier properties were observed for nanocellulose-reinforced composites, where nanocellulose partially impermeable nanoparticles decreased gas permeability effectively. However, for nanocellulose-based materials, the higher gas barrier performance is jeopardized by water absorption and shape deformation under high humidity conditions which is a challenge for maintaining properties in material applications. Thus, numerous investigations have been done to solve the problem of water absorption in nanocellulose-based materials. In this literature review, gas barrier properties of pure, layer-by-layer and composite nanocellulose films are investigated. The possible theoretical gas barrier mechanisms are described, and the prospects for nanocellulose-based materials are discussed.


Asunto(s)
Celulosa , Nanopartículas , Permeabilidad , Polímeros
12.
Bioresour Technol ; 343: 126061, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34597806

RESUMEN

Hydrothermal pretreatment (HTP) using only water offers great potential to reduce the overall cost of the bioconversion process. However, traditional HTP performed in a batch has limitations in removing lignin and often needs to be performed under severe conditions to achieve reasonable pretreatment effects. Lignin left in the pretreated residue at these conditions is also highly condensed, thus possessing an even more adverse impact on the hydrolysis process, which requires high enzyme loadings. To address these technical challenges, HTP performed in a flow-through configuration was developed to simultaneously achieve near-complete hemicellulose recovery, high lignin removal and high sugar release. Despite facing challenges such as potentially large water usage, flow-through HTP still represents one of the most cost-effective and eco-friendly pretreatment methods. This review mainly covers the latest cutting-edge innovations of flow-through HTP along with structural and compositional changes of cellulose, hemicellulose, and lignin before and after pretreatment.


Asunto(s)
Celulosa , Lignina , Biomasa , Hidrólisis , Agua
13.
Bioresour Technol ; 343: 126071, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34606923

RESUMEN

One of the potential bioresources for bioethanol production is Napier grass, considering its high cellulose and hemicellulose content. However, the cost of pretreatment hinders the bioethanol produced from being economical. This study examines the effect of hydrothermal process with dilute acid on extruded Napier grass, followed by enzymatic saccharification prior to simultaneous saccharification and co-fermentation (SScF). Extrusion facilitated lignin removal by 30.2 % prior to dilute acid steam explosion. Optimum pretreatment condition was obtained by using 3% sulfuric acid, and 30-min retention time of steam explosion at 190 °C. Ethanol yield of 0.26 g ethanol/g biomass (60.5% fermentation efficiency) was attained by short-term liquefaction and fermentation using a cellulose-hydrolyzing and xylose-assimilating Saccharomyces cerevisiae NBRC1440/B-EC3-X ΔPHO13, despite the presence of inhibitors. This proposed method not only reduced over-degradation of cellulose and hemicellulose, but also eliminated detoxification process and reduced cellulase loading.


Asunto(s)
Saccharomyces cerevisiae , Xilosa , Celulosa/metabolismo , Etanol , Fermentación , Hidrólisis , Lignina/metabolismo , Saccharomyces cerevisiae/metabolismo , Ácidos Sulfúricos
14.
Bioresour Technol ; 343: 126086, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34624468

RESUMEN

The anaerobic co-digestion (AcoD) of microalgae is a prospective option for generating biomethane from renewable sources. This study investigates the effects of inoculum-to-substrate ratio (ISR), C/N ratio and biochar (BC) load on the AcoD of Chlorella vulgaris and cellulose. An initial augmentation of BC at ISR 0.5-0.9 and C/N ratio 10-30 offered a pH buffering effect and resulted in biomethane yields of 233-241 mL CH4/g VS, corresponding to 1.8-4.6 times the controls. BC addition ameliorated significantly AcoD, supporting the digestate stability at less favourable conditions. The effect of the process variables was further studied with a 23 factorial design and response optimisation. Under the design conditions, the variables had less influence over methane production. Higher ISRs and C/N ratios favoured AcoD, whereas increasing amounts of BC reduced biomethane yield but enhanced production rate. The factorial design highlighted the importance of BC-load on AcoD, establishing an optimum of 0.58 % (w/v).


Asunto(s)
Chlorella vulgaris , Anaerobiosis , Biocombustibles , Reactores Biológicos , Celulosa , Carbón Orgánico , Digestión , Metano , Estudios Prospectivos
15.
Bioresour Technol ; 343: 126100, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34626760

RESUMEN

The development of lignocellulosic biorefineries requires a first stage of pretreatment which enables the efficient valorization of all fractions present in this renewable material. In this sense, this review aims to show the main advantages of hydrothermal treatment as a first step of a biorefinery infrastructure using hardwood as raw material, as well as, main drawback to overcome. Hydrothermal treatment of hardwood highlights for its high selectivity for hemicelluloses solubilization as xylooligosaccharides (XOS). Nevertheless, the suitable conditions for XOS production are inadequate to achieve an elevate cellulose to glucose conversion. Hence, several strategies namely the combination of hydrothermal treatment with delignification process, in situ modification of lignin and the mixture with another renewable resources (concretely, seaweeds, and by-products generated in the food industry with high sugar content) were pinpointed as promising alternative to increase the final ethanol concentration coupled with XOS recovery in the hydrolysate.


Asunto(s)
Lignina , Oligosacáridos , Celulosa , Glucuronatos , Hidrólisis
16.
Bioresour Technol ; 343: 126113, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34648965

RESUMEN

Soluble compounds produced during the enzymatic hydrolysis of lignocelluloses hampers cellulose conversion. Cellobiose and vanillin most severely inhibited the effect of cellobiohydrolase I. A concentration-dependent negative cooperative effect was found between cellobiose and vanillin. The combined inhibitory effect was about 83.5% of the cellobiose and 88.1% of the vanillin when their concentration was 20 mg/ml. However, the negative synergy could be eliminated by excessive enzyme loading. Differences in their binding sites on the catalytic domain of cellobiohydrolase I lead to negative synergistic inhibition, which should be considered in devising strategies to alleviate this effect. Combined ß-glucosidase and PEG addition at an appropriate dose was feasible to balance cost and hydrolytic efficiency. To achieve efficient hydrolysis, especially at high solid concentrations, it is important to understand the synergistic inhibition between these inhibitors.


Asunto(s)
Celulasa , Zea mays , Celulosa , Celulosa 1,4-beta-Celobiosidasa , Hidrólisis
17.
Bioresour Technol ; 343: 126123, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34653621

RESUMEN

As a clean and renewable energy, bioenergy is one of the most promising alternatives to fossil fuels. Lignocellulose possesses great potential for bioenergy production, but the recalcitrant and heterogeneous structure limits its application. Pretreatment technology offers an effective solution to fractionate the main components of the lignocellulose and uncover the available cellulose. The obtained feedstock can be applied to bioconversion into energy, e.g., bioethanol, biogas, biohydrogen, etc. Here, the current state of lignocellulose pretreatment technologies was comprehensively reviewed, the advances in bioenergy production from pretreated lignocellulose was described, with particular attention to key challenges involved. Several new strategies for overcoming pretreatment barriers to realize highly efficient lignocellulose bioconversion were highlighted. The insights given in this review will facilitate further development on lignocellulosic bioenergy production, towards addressing the global energy crisis and climate change related to the use of fossil fuels.


Asunto(s)
Biocombustibles , Lignina , Biomasa , Celulosa
18.
Bioresour Technol ; 343: 126122, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34653625

RESUMEN

The lignin-first biorefinery approach was desirable to produce lignin-derived products by protecting the linkages of lignin and reducing condensation reaction. However, so far lignin-first strategy studies were mainly carried out under harsh conditions, causing serious destruction of lignin structure and reduction of chemically labile linkages, which was not conducive to enhance value of lignin adequately. In this work, mild fractionation of poplar via lignin-first strategy using dioxane/methanol at 80 °C was developed for purposely extracting reactive lignin with a relatively higher yield (>50%), purity (>99%), ß-O-4' linkages and p-hydroxybenzoate group as compared with controlled sample. In addition, glucose yield of cellulose-rich residue under lignin-first strategy was significantly enhanced to 98.57% due to the superior cellulase adsorption abilities, which was obviously higher than the controlled group (53.88%). Overall, this mild lignin-first strategy was promising to fractionate lignocellulose into reactive lignin and fermentable glucose, thereby achieving full utilization of lignocellulose biomass.


Asunto(s)
Lignina , Populus , Biomasa , Celulosa , Hidrólisis
19.
Bioresour Technol ; 343: 126158, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34673192

RESUMEN

Organosolv pretreatment can be considered as the core of the lignocellulosic biomass fractionation within the biorefinery concept. Organosolv facilitates the separation of the major fractions (cellulose, hemicelluloses, lignin), and their use as renewable feedstocks to produce bioenergy, biofuels, and added-value biomass derived chemicals. The efficient separation of these fractions affects the economic feasibility of the biorefinery complex. This review focuses on the simulation of the organosolv pretreatment and the optimization of (i) feedstock delignification, (ii) sugars production (mainly from hemicelluloses), (iii) enzymatic digestibility of the cellulose fraction and (iv) quality of lignin. Simulation is used for the technoeconomic optimization of the biorefinery complex. Simulation and optimization implement a holistic approach considering the efficient technological, economic, and environmental performance of the biorefinery operational units. Consequently, an optimized organosolv stage is the first step for a sustainable, economically viable biorefinery complex in the concept of industrial ecology and zero waste circular economy.


Asunto(s)
Celulosa , Lignina , Biomasa , Hidrólisis
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 266: 120433, 2022 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-34601370

RESUMEN

Advances in food monitoring benefit tremendously from the naked-eye observation and device-miniaturization of colorimetric and fluorometric methods. Intelligent food packaging, containing a built-in sensor inside food bags, is capable of real-time monitoring of food quality by visibly discernible out-put signals, which effectively ensures food safety. We synthesized a donor-π-acceptor (D-π-A) compound DPABA, and disclosed its fluorescence response to amines. According to quantum chemical calculations, DPABA is apt to D-A coupling in aggregated state, causing the formation of exciplex/excimer together with intermolecular charge/energy transfer to the disadvantage of light emission; while the evasion of amine vapors would decouple the intermolecular D-A interactions to induce stronger emission with shorter wavelength. Utilizing the amine vapor generated by fish, DPABA can serve as an indicator for freshness monitoring. To create an intelligent food package, the compound was made into cellulose film, which was further cut into smart labels to be encapsulated into food bags. The as-prepared smart label exhibits red color under ambient light and glows weak red emission under UV light, while it turns into faint yellow color in response to putrid fish, and its emission changes to bright cyan. The output signals can be accurately recorded by instrument, and detected by naked eye, suggesting high signal contrast. In addition, the smart label exhibits different changing scope in response to different degree of freshness, showing high potential for in-field detection.


Asunto(s)
Embalaje de Alimentos , Calidad de los Alimentos , Animales , Celulosa , Color , Concentración de Iones de Hidrógeno
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