Search Results (8)

Biofuel, an inexhaustible fuel source, plays a pivotal role in the contemporary era by diminishing the dependence on non-renewable energy sources and facilitating the mitigation of CO₂ emissions. Due to the many constraints in existing technology and the resulting increased costs, the production of biofuels on a large scale is a laborious process. Furthermore, the methods used to convert varied feedstock into the intended biofuel may vary based on the specific techniques and materials involved. The demand for bioethanol is increasing worldwide due to the implementation of regulations by world nations that mandates the blending of bioethanol with petrol. In this regard, second-generation bioethanol made from lignocellulosic biomass is emerging at a rapid rate. Pre-treatment, hydrolysis, and fermentation are some of the technical, practical, and economic hurdles that the biochemical conversion method must overcome. Nanoparticles (NPs) provide a very effective approach to address the present obstacles in using biomass, due to their selectivity, energy efficiency, and time management capabilities, while also reducing costs. NPs smaller dimensions allow them to be more effective at interacting with lignocellulosic components at low concentrations to release carbohydrates that can be utilized to produce bioethanol. This article provides a concise overview of various biofuels and the nanotechnological advancements in producing it, with a particular emphasis on ethanol. It provides a detailed discussion on the application of nanotechnology at each stage of ethanol production, with a particular emphasis on understanding the mechanism of how nanoparticles interact with lignocellulose. Full article

Petroleum-derived polymers, such as polyethylene and polypropylene, are commonly used in food packing industries knowing the fact that these polymers cause serious threats to the ecosystem. Therefore, the development of low-cost, environmentally friendly, and biodegradable polymers to address this issue is an urgent need of the hour. Bacterial nanocellulose (BNC), with its extraordinary and differentiated properties, is gaining special attention in the food packaging industry. To reduce the cost, several low-cost substrates are utilized for the production of BNC. Therefore, the present study is focused on the production of low-cost BNC and its subsequent functionalization for smart packaging applications. Full article

In this study, multifunctional lithium-doped bismuth ferrite [BiFe_1−xLi_xO₃]-graphene nanocomposites (x = 0.00, 0.02, 0.04, 0.06) were synthesized by a sol-gel and ultrasonication assisted chemical reduction method. X-ray diffraction and FESEM electron microscopy techniques disclosed the nanocomposite phase and nanocrystalline nature of [BiFe_1−xLi_xO₃]-graphene nanocomposites. The FESEM images and the EDX elemental mapping revealed the characteristic integration of BiFe_1−xLi_xO₃ nanoparticles (with an average size of 95 nm) onto the 2D graphene layers. The Raman spectra of the [BiFe_1−xLi_xO₃]-graphene nanocomposites evidenced the BiFe_1−xLi_xO₃ and graphene nanostructures in the synthesized nanocomposites. The photocatalytic performances of the synthesized nanocomposites were assessed for ciprofloxacin (CIP) photooxidation under UV-visible light illumination. The photocatalytic efficiencies of [BiFe_1−xLi_xO₃]-graphene nanocomposites were measured to be 42%, 47%, 43%, and 10%, for x = 0.00, 0.02, 0.04, 0.06, respectively, within 120 min illumination, whereas the pure BiFeO₃ nanoparticles were 21.0%. BiFe_1−xLi_xO₃ nanoparticles blended with graphene were explored as cathode material and tested in a microbial fuel cell (MFC). The linear sweep voltammetry (LSV) analysis showed that the high surface area of BiFeO₃ was attributed to efficient oxygen reduction reaction (ORR) activity. The increasing loading rates of (0.5–2.5 mg/cm²) [BiFe_1−xLi_xO₃]-graphene composite on the cathode surface showed increasing power output, with 2.5 and 2 mg/cm² achieving the maximum volumetric power density of 8.2 W/m³ and 8.1 W/m³, respectively. The electrochemical impedance spectroscopy (EIS) analysis showed that among the different loading rates used in this study, BiFeO₃, with a loading rate of 2.5 mg/cm², showed the lowest charge transfer resistance (R_ct). The study results showed the potential of [BiFe_1−xLi_xO₃]-graphene composite as a cost-effective alternative for field-scale MFC applications. Full article

The present study explores the use of carbon dots coated with Iron (II, III) oxide (Fe₃O₄) for its application as an anode in microbial fuel cells (MFC). Fe₃O₄@PSA-C was synthesized using a hydrothermal-assisted probe sonication method. Nanoparticles were characterized with XRD, SEM, FTIR, and RAMAN Spectroscopy. Different concentrations of Fe₃O₄- carbon dots (0.25, 0.5, 0.75, and 1 mg/cm²) were coated onto the graphite sheets (Fe₃O₄@PSA-C), and their performance in MFC was evaluated. Cyclic voltammetry (CV) of Fe₃O₄@PSA-C (1 mg/cm²) modified anode indicated oxidation peaks at −0.26 mV and +0.16 mV, respectively, with peak currents of 7.7 mA and 8.1 mA. The fluxes of these anodes were much higher than those of other low-concentration Fe₃O₄@PSA-C modified anodes and the bare graphite sheet anode. The maximum power density (Pmax) was observed in MFC with a 1 mg/cm² concentration of Fe₃O₄@PSA-C was 440.01 mW/m², 1.54 times higher than MFCs using bare graphite sheet anode (285.01 mW/m²). The elevated interaction area of carbon dots permits pervasive Fe₃O₄ crystallization providing enhanced cell attachment capability of the anode, boosting the biocompatibility of Fe₃O₄@PSA-C. This significantly improved the performance of the MFC, making Fe₃O₄@PSA-C modified graphite sheets a good choice as an anode for its application in MFC. Full article

Biofuel is one of the best alternatives to petroleum-derived fuels globally especially in the current scenario, where fossil fuels are continuously depleting. Fossil-based fuels cause severe threats to the environment and human health by releasing greenhouse gases on their burning. With the several limitations in currently available technologies and associated higher expenses, producing biofuels on an industrial scale is a time-consuming operation. Moreover, processes adopted for the conversion of various feedstock to the desired product are different depending upon the various techniques and materials utilized. Nanoparticles (NPs) are one of the best solutions to the current challenges on utilization of biomass in terms of their selectivity, energy efficiency, and time management, with reduced cost involvement. Many of these methods have recently been adopted, and several NPs such as metal, magnetic, and metal oxide are now being used in enhancement of biofuel production. The unique properties of NPs, such as their design, stability, greater surface area to volume ratio, catalytic activity, and reusability, make them effective biofuel additives. In addition, nanomaterials such as carbon nanotubes, carbon nanofibers, and nanosheets have been found to be cost effective as well as stable catalysts for enzyme immobilization, thus improving biofuel synthesis. The current study gives a comprehensive overview of the use of various nanomaterials in biofuel production, as well as the major challenges and future opportunities. Full article

The past decade has witnessed a phenomenal rise in nanotechnology research due to its broad range of applications in diverse fields including food safety, transportation, sustainable energy, environmental science, catalysis, and medicine. The distinctive properties of nanomaterials (nano-sized particles in the range of 1 to 100 nm) make them uniquely suitable for such wide range of functions. The nanoparticles when manufactured using green synthesis methods are especially desirable being devoid of harsh operating conditions (high temperature and pressure), hazardous chemicals, or addition of external stabilizing or capping agents. Numerous plants and microorganisms are being experimented upon for an eco–friendly, cost–effective, and biologically safe process optimization. This review provides a comprehensive overview on the green synthesis of metallic NPs using plants and microorganisms, factors affecting the synthesis, and characterization of synthesized NPs. The potential applications of metal NPs in various sectors have also been highlighted along with the major challenges involved with respect to toxicity and translational research. Full article

Waste glycerol is the main by-product generated during biodiesel production, in an amount reaching up to 10% of the produced biofuel. Is there any method which allows changing this waste into industrial valuable compounds? This manuscript describes a method for valorization of crude glycerol via microbial bioconversion. It has been shown that the use of free and immobilized biocatalysts obtained from Gluconobacter oxydans can enable beneficial valorization of crude glycerol to industrially valuable dihydroxyacetone. The highest concentration of this compound, reaching over 20 g·L⁻¹, was obtained after 72 h of biotransformation with free G. oxydans cells, in a medium containing 30 or 50 g·L⁻¹ of waste glycerol. Using a free cell extract resulted in higher concentrations of dihydroxyacetone and a higher valorization efficiency (up to 98%) compared to the reaction with an immobilized cell extract. Increasing waste glycerol concentration to 50 g·L⁻¹ causes neither a faster nor higher increase in product yield and reaction efficiency compared to its initial concentration of 30 g·L⁻¹. The proposed method could be an alternative for utilization of a petrochemical waste into industry applicated chemicals. Full article