Biomass Conversion and Biorefinery最新文献

Previously, we developed a series of processes that involved chemical and enzymatic treatments to extract and separate the fibers from alfa leaves, while also preserving their native mechanical properties, by optimizing the implementation parameters. In this study, we describe the morphology of the alfa leaf, characterize the alfa fibers, and study the influence of different treatments on their crystalline structure, their colorimetric, and thermal properties. This work mentions the application of Weibull statistics to analyze the mechanical properties of alfa fibers, which helps in understanding the probability of failure under different stress conditions. Additionally, we also examined the difference in mechanical properties between a fiber bundle and a single fiber. The results show that the cellulose has not been attacked after different treatments, and the thermal stability of the fibers has improved. X-ray analysis shows that the crystallinity index of the fibers increased by about 16.4% for the alkaline and pectinase treatments. Also, we noticed that the enzymatic treatments led to reduction in the dispersion of mechanical properties. Moreover, we observed that the bundle with a smaller diameter is stronger than the one with a larger diameter. Under tensile loading, it behaves similarly to a unitary fiber, demonstrating a single break.Keywords: Enzymatic treatments, Alkaline treatment, Thermal stability, Weibull approach, Mechanical properties, Single fiber.

Microwave-assisted deep eutectic solvent (DES) pretreatment using choline chloride-formic acid (ChCl: FA) is investigated as a rapid method for lignocellulose fractionation in sorghum biomass for bioethanol production. This study focuses on enhancing cellulose retention and its digestibility while effectively removing the majority of lignin and hemicelluloses. Optimal conditions (ChCl: FA ratio of 1:3, 20 min, 250 W) resulted in 98% cellulose retention and 97% purity, respectively. Furthermore, X-ray diffraction (XRD) and scanning electron microscopy (SEM) were employed to investigate the morphological and crystallinity changes in the biomass following pretreatment. The XRD and SEM characterizations demonstrated that the structural alterations and decreased crystallinity of the pretreated sorghum biomass significantly enhanced cellulose digestibility. Compared to conventional method, this process exhibited a fourfold reduction in energy consumption. The synergetic effect of high cellulose purity and yield led to a maximum ethanol yield of 0.57 g/g cellulose at minimal enzyme dosage (10 FPU) and a short fermentation time (27 h). GC–MS analysis confirms the purity of the obtained bioethanol. The proposed method paves the way for substantial economic benefits in biorefinery, supporting the principles of a circular economy by promoting sustainable and efficient resource utilization.

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The continuous search for sustainable and cost-effective water treatment solutions led to the investigation of activated mahua seed cake for wastewater treatment. The mahua seed cake was activated using hydrogen peroxide and phosphoric acid to develop an eco-friendly adsorbent. The activated material was characterized by Fourier Transform Infrared Spectroscopy (FTIR), Field Emission Scanning Electron Microscopy (FESEM), Brunauer Emmett Teller (BET) surface area analysis, and pH at zero point of charge. The results confirmed that phosphoric acid activation introduced the phosphate (PO₄³⁻) group, as demonstrated by FTIR analysis. The FESEM micrograph revealed a very porous channel-like topology that was incredibly feasible for enhancing dye uptake. Following the adsorption of methylene blue (MB) onto phosphoric acid-modified de-oiled mahua seed (PDM), the pHzpc was found to be 7.2, confirming the material’s viability in neutral pH media. The pseudo-second kinetic (R² = 0.999) and Langmuir isotherm models (R² = 0.998) were found to best describe the mechanism of interaction. The reported negative ∆G⁰ value denotes the spontaneity of the scavenging process, which is endothermic and accompanied by increased randomness. Within the first 15 min, 95% of adsorption took place, and by 45 min, it reached saturation (98.25%). Inducing > 74% regeneration with dilute hydrochloric acid provided multiple-cycle reusability. Industrial wastewater was successfully treated up to 56.77%. With a neutral pH range, the material performs well with an adsorption ability of 60.15 mg/g. These findings suggest that phosphoric acid-activated mahua seed cake is a viable and sustainable option for wastewater treatment.

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This study explored the utility of underutilized avocado peels for extracting cellulose nanofibers (CNFs). Mild oxalic acid hydrolysis assisted by steam explosion was employed after alkali hydrolysis and chlorine-free bleaching to prepare cellulose nanofibers. The structural, atomic, and elemental features of the extracted fibers were studied using Fourier transform infrared spectroscopy (FTIR), ¹³C solid-state nuclear magnetic resonance (¹³C NMR) spectroscopy, and energy dispersive X-ray (EDAX) analysis, respectively. The crystallinity index of the nanofibers was 87%, which was 53% greater than that of the crude sample. The elution of hemicellulose and lignin was evident from the scanning electron microscopy (SEM) images, and the nanofibers had a fiber diameter of 30–82 nm according to the transmission electron microscopy (TEM) analysis. The applied chemical treatment also elevated the thermal stability of the fibers. The extracted fibers can be applied in numerous fields, including electronics, packaging, automobiles, biomedicine, and cosmetics.

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Keeping sustainability concept in view with combating the crises risen from pollution of environment with dyes, this study aims to efficiently remove methylene blue (MB) dye from wastewaters using an agricultural waste derived sorbent produced by pyrolyzing of neem tree shells at 700 °C. An extensive scrutinization was performed both on the effects physiochemical variables and adsorption properties of the recruited biochar. Results showed that the prepared bio-charcoal possesses a promising textural property, leading to a high capability to retrieve MB from aqueous solutions at pH range of 8.5 to 9.0. The equilibrium of adsorption was achieved within time durations lesser than 200 min of stirring. Several mathematical models were applied to elucidate the kinetic behavior, and the outcomes vouchsafed the rate-controlling role of adsorbate-adsorbent interaction and the effect of intraparticle diffusion in the adsorption process. The equilibrium adsorption behavior was extensively evaluated through various two-parameter and three-parameter isotherms, revealing the monolayer Langmuir mechanism of adsorption and an adsorption capacity as high as 134.13 mg/g at ambient temperature (25 °C). The maximal adsorption capacity (q_max of Langmuir) increased from 126.39 mg/g (at 15 °C) to 139.59 mg/g (at 35 °C), revealing the endothermic nature of MB adsorption, confirmed by the positive enthalpy (∆H°, 14.07 kJ mol⁻¹). The spontaneous adsorption of MB (∆G° at 25 °C = − 27.02 kJ mol⁻¹) along with high adsorption capability and other properties of the produced biochar makes it a promising sorbent with high potential for usage in real MB-laden wastewaters.

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The coconut husk (CH) is a significant byproduct of the green coconut agroindustry (which produces coconut water, coconut oil, and coconut milk), constituting approximately 15% of the total fruit weight. CH is often discarded improperly, leading to significant environmental issues. This CH decomposes over several years, contributing to greenhouse gas emissions and contaminating soils and water bodies. Traditionally, the CH has been used for charcoal production, agricultural substrate, and manufacturing products. However, there is increasing interest in valorizing CH through biotechnological processes to produce higher-value bioproducts, such as biofuels and enzymes. This review article assesses the latest trends in CH utilization, exploring both traditional methods and innovative biotechnology-based technologies. Bibliometric analysis on CH utilization indicated a significant increase in publications over the past decade, highlighting the potential of fermentation-based approaches to convert CH lignocellulosic content into bioproducts, such as biofuel, enzymes and biomaterials that have a higher commercial value than those traditionally obtained. Reports in the literature also suggest that the pretreatment methods applied enhance bioconversion yields, leading to higher bioproduct yields. These results indicate new advancements in CH management and the development of cleaner technologies for enhanced bioproduct synthesis. This approach to biotechnological production can mitigate the environmental impact of coconut waste while strengthening economic development and ecological conservation.

This article aims to evaluate the environmental impacts of different centralized biowaste management scenarios from the hospitality sector of the tourist city of João Pessoa, Brazil. To this end, a life cycle assessment was carried out, comparing different scenarios for the centralized treatment of biowaste based on territorial characteristics. The life cycle inventory was built using the Ecoinvent 3.0.1 database and Simapro software. The environmental impacts were assessed using the CML method, considering eight categories of impacts, such as global warming by greenhouse gases (GHG) and ozone layer depletion. The results show that the disposal of biowaste in João Pessoa's landfill (current management scenario) has significant environmental impacts when compared to diverting this waste to composting or anaerobic digestion, for example, in the global warming category, where the net impact of the landfill is 1.045 kg CO2 eq, while that of composting and anaerobic digestion is 0.18 and 0.17 kg CO2 eq, respectively. Furthermore, the comparison between centralized composting and anaerobic digestion indicates that composting is the scenario that produces the least negative environmental impacts for 62% of the categories analyzed. Therefore, this article points out that the current management of biowaste from the hotel sector in João Pessoa has several negative environmental impacts, making it necessary to implement actions that promote diverting biowaste flow from the landfill to other centralized treatment systems. It should be noted that an interdisciplinary analysis is needed to assess the social and economic aspects of the best option for treating and recovering organic waste.

India’s areca nut tree-based processing industry yields a significant annual waste volume estimated between 4.5 and 5.4 million tons in the form of areca sheaths. Efforts to repurpose these sheaths as sustainable alternatives to plastic materials like cups, plates, and boxes are gaining traction, aiming to reduce the environmental impact of such waste. Using Geographic Information System (GIS) technology, this research investigates the factors influencing the geographic distribution of enterprises utilizing areca sheath-based products across diverse Indian regions. The physiochemical properties of discarded areca sheaths and various by products from small and medium enterprises were thoroughly examined. The analysis uncovers substantial potential in harnessing areca waste resources. Findings from characterization studies reveal a notable abundance of fiber content, approximately 35.14 ± 1.25%, while exhibiting relatively lower levels of protein (around 3.45 ± 0.78), ether extract (roughly 2.71 ± 0.56), and a total phenolic content of 2.72 ± 0.54 mg GAE per gram. Furthermore, the study employs ICP-MS to delve into the mineral elements and heavy metal contents within the ASW. The sequence of macro factors observed in the analysis followed the order: K > Ca > P > Mg > S > Mn > Zn > Na > Fe > B > Cu. Distinct Fe, Mn, Zn, and B concentrations were identified, ranging between 2376 and 72.33 μg·g⁻¹. This research illuminates the environmental implications of these wastes and emphasizes potential avenues for recycling and reusing, advocating for a more sustainable approach to managing agricultural byproducts.

Environmental pollutants, such as invasive weeds and synthetic dyes, pose significant threats to ecosystems and human health. Parthenium weed (PW), an aggressive invader, disrupts native biodiversity, while synthetic dyes, particularly Malachite Green (MG), is persistent and considered parasiticide in aquaculture. This study explores synthesis of green fluorescent carbon dots (WCDs) from flowers of PW using simple pyrolysis method for photodegradation and sensing of Fe³⁺ ions. The synthesized WCDs, with a spherical size of 3.57 nm, demonstrated remarkable efficiency in the degradation of MG dye, achieving a degradation efficiency of 96.5% within 120 min of reaction time. The degradation kinetics followed a first-order reaction with a rate constant of 0.0257 min⁻¹ at pH 10.0. Furthermore, WCDs exhibited a low limit of detection (LoD) 4.4 μM and limit of quantification (LoQ) 14.6 μM for ferric ion sensing, underscoring their potential for sensitive detection applications. The band gap of WCDs was determined to be 2.65 eV, indicative of their optical properties and potential for photocatalytic applications. The synthesis of WCDs from an abundant and renewable biomass source underscores the eco-friendly nature of the proposed approach, further enhancing its potential for real-world applications.

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Indonesia as the world’s largest palm oil producer produces large amounts of waste during palm oil processing, one of which is oil palm empty fruit bunches (OPEFB). OPEFB can be converted into biochemicals, bioethanol, and lignin. This study aims to produce bioethanol from OPEFB using response surface method (RSM) analysis with the addition of the bleaching process and Cellic® Ctec2 and Cellic® Ctec3 enzymes used in the saccharification process. In addition, lignin was isolated from black liquor in the pretreatment process with the CO₂ bubbling method. Bioethanol production begins with pulp production by the alkaline (NaOH) steam explosion of OPEFB followed by bleaching. Subsequently, enzymatic saccharification with three parameters: enzyme concentration, solid loading, and temperature, was carried out. Saccharomyces cerevisiae was used in the fermentation to produce ethanol. Meanwhile, the lignin isolation was carried out by injecting CO₂ gas 2 L/min into the black liquor solution with variations in time. The results showed that the bleaching processes significantly increased cellulose content and reduced lignin content in OPEFB, with pulp yields reaching 91% and 89% for the first and second stages of bleaching, respectively, demonstrating high efficiency in preparing materials for sugar recovery. Optimal conditions were achieved using RSM analysis at an enzyme concentration of 30 FPU, solid loading of 20% (w/v), and temperature of 50 °C with a sugar content of 12.63% and ethanol of 2.14%. The implication of the bleaching process showed a lower concentration of 1.2% ethanol when compared to only unbleached pulp which produced 2.42% ethanol. In addition, the use of Cellic® Ctec3 enzyme produced higher sugar and ethanol content with 14.04% sugar and 4.42% ethanol compared to Cellic® Ctec2. On the other hand, the largest lignin isolation result was obtained at a processing time of 2 h with a yield of 1.16% and purity of 96.94%.

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