Biomass Conversion and Biorefinery最新文献

This study employed response surface methodology (RSM), artificial neural networks (ANN), and computational fluid dynamics (CFD) to optimize the mass fraction of total anthocyanins and redness index from pericarp blood orange waste (PBOW). A total of five independent variables were examined: ultrasonic power (ranging from 100 to 300 W), ultrasonic time (5 to 30 min), agitation speed (80 and 160 rpm), ethanol concentration (0 to 50%), and the solid-to-solvent ratio (0.25 to 0.75). The ANN method effectively forecast the experimental data, allowing for a precise model of the nonlinear relationships between extraction parameters and anthocyanin mass fraction and redness index. Consequently, these findings demonstrated that ultrasonic power and ethanol concentration were the most influential independent variables affecting anthocyanin mass fraction and redness index. The analysis revealed that ANN model achieved a high coefficient of determination (R² = 0.99451), surpassing the predictive accuracy of both RSM and the CFD approaches. The optimal conditions, as determined using the RSM-ANN model, consisted of 270 W of ultrasonic power, 20.30 min of ultrasonic time, 140 rpm agitation speed, an ethanol concentration of 37.5%, and a solid to liquid ratio of 0.375. Additionally, the economic evaluation provided an estimate of the anthocyanin production from orange pericarp wastes. Thus, the combination of these simulated approaches substantially improved the efficiency and yield of anthocyanin extraction from pericarp blood orange waste, resulting in a practical and environmentally friendly method for utilizing these agricultural by-products.

Graphical Abstract

Since lignocellulosic biomass is the only naturally occurring renewable feedstock that contains aromatic rings, it has been recognised as a promising alternative to fossil fuels in chemicals and fuel derivatives. Just over five percent of lignin is employed in discounted commercial applications, primarily as a subpar fuel for heat and power or as a concrete additive (lignosulfonate). Until now, the controlled fabrication of carboxylated lignin with a well-defined structure and composition remains a great challenge. Herein, we developed a simple approach using kraft lignin as the raw material of the catalyst, denoted as (Lignin-COOH), by a planetary ball mill in the presence of dry ice as an oxidant ensued by protonation. The catalyst contained aliphatic moieties with desirable thermal stability and a carboxylic group (2.7 mmol g^–1). Lignin-COOH hydrolysis cellulose to glucose (88.6%), while the eucalyptus (62%) glucose within 15 min at 180 °C in (120 ppm) HCl.

Biomass combustion in fixed-bed reactors generates significant emissions, including carbon monoxide (CO), nitrogen oxides (NO_x), sulfur oxides (({SO}_{x})), and carbon dioxide (({CO}_{2})), which contribute to air pollution and climate change. Conventional combustion methods struggle to balance combustion efficiency with emissions control, often resulting in pollutant levels exceeding permissible exposure limits for safe domestic and industrial applications. This study investigates the potential of oxy-fuel combustion as a strategy to mitigate these emissions while improving combustion efficiency in carbonized rice husk briquettes. Combustion experiments were conducted in a fixed-bed reactor, with emissions of NO_x, CO, CO₂ and SO_x measured using a Testo 350 analyzer. A response surface methodology (RSM) was employed to assess the statistical significance of the measured emissions and to provide a visual representation of their relationship with oxy-fuel mass flux (0.1–0.15 kg/m²s), oxygen-to-carbon dioxide ratio (20–40%), and binder content (3.5–9.7 wt.%). The results indicate that NO_x emissions peak near stoichiometric conditions and decrease in fuel-rich and fuel-lean environments, while CO emissions are highest under fuel-rich conditions due to incomplete combustion but decline with improved combustion efficiency. CO₂ emissions increase with mass flux, peaking at stoichiometric conditions, while SO_x emissions depend on sulfur content and combustion conditions, rising near stoichiometric levels. A comparison with regulatory limits suggests that NO_x and SO_x emissions are within permissible industrial limits but may require additional control measures for domestic use. Furthermore, the study compares emissions with those reported in previous literature, demonstrating that oxy-fuel combustion reduces NO_x emissions more effectively than conventional air combustion. These findings confirm that oxy-fuel combustion of rice husk briquettes can optimize biomass energy utilization while maintaining emissions within acceptable limits.

The catalytic conversion of cellulose and its sugars to 5-hydroxymethylfurfural (5-HMF) demonstrates enormous potential as a key Link in the sustainable production of high-value platform chemicals. Based on its varied chemical characteristics and potential availability, 5-HMF, an essential multifunctional bio-based furan platform component, May effectively transform into a wide range of high-value-added derivatives, Making it a perfect renewable substitute for fossil fuels. In the past several years, the topic of 5-HMF has continued to rise in popularity, and the advancement of numerous research works has greatly enriched the types of raw Materials used in its preparation and expanded the corresponding preparation methods. This article thoroughly examines the intrinsic mechanism of 5-HMF catalytic conversion and primarily summarizes the research progress on effective 5-HMF conversion catalytic systems in recent years, with a focus on the impacts of catalysts and solvent systems on cellulose and derived sugars. Finally, an in-depth exploration and prospect of the research trends in the preparation of 5-HMF from cellulose and its sugars in the future are conducted, with the hope of providing guidance and inspiration for related research in the future.

Hops (Humulus lupulus) are essential in beer production, as their presence in both unfertilized (seedless) and fertilized (seeded) inflorescences produces lupulin, a powder rich in α-acids and essential oils that enhance bitterness and aroma. Hop cultivation in Brazil has gained prominence with the establishment of certified seedling nurseries, reaching prices of up to $60 per kg in 2025. Global demand for hops is rising, driven by the craft beer industry and major producers like the U.S., Germany, and Australia. However, logistical challenges still hinder its economic viability in Brazil. In this work, commercial pellet hops produced and supplied by Atlântica Hops (Juquiá – SP) were used for supercritical fluid extraction with CO₂ (SFE-CO₂). The aim was to obtain different extracts, including the spent hop, and compare them to determine the content of α-acids, essential oils, and sensory profiles. Including the biorefinery concept, the antifungal and antioxidant potential and the chemical composition were evaluated to explore their use as raw material for other value-added bioproducts. Conventional hop extraction yielded 15%, with 9% α-acid content, while SFE-CO₂ extraction reached 72% α-acids. The SFE-CO₂ extract proved to be more commercially viable due to its smaller volume, easier storage, and 20% higher yield in beer production. The extraction of spent hop showed higher antioxidant activity and was rich in carotenoids, flavonoids, and phenolics. SFE-CO₂ technology presents a promising opportunity for the hop production chain in Brazil, optimizing economic viability and generating additional revenue through by-products.

Graphical Abstract

Bacterial symbionts associated with Himalayan endangered medicinal plants are less explored for their biotechnological potential. This study reports beneficial characteristics of microalgal growth-promoting bacterial symbiont Bacillus sp. AHE12 isolated from Himalayan endangered medicinal plant. Symbiont Bacillus sp. AHE12 had possessed potential plant growth promoting (PGP) characteristics including secretion of growth-promoting hormone IAA through tryptophan metabolism. Symbiont Bacillus sp. AHE12 significantly enhanced microalgal growth and photosynthesis in synthetic co-culturing system through IAA secretion. The interaction between AHE12 and the microalga Micractinium sp. GA001 has been comprehensively analyzed using various synthetic co-cultivation system setups. Symbiont AHE12 was found to be metabolically stable, improved microalgal growth (up to 47%), and enhanced photosynthesis efficiency (up to 23.68% chlorophyll b) for a prolonged duration (up to 28 days) in the synthetic co-culturing systems. A complete genome characterization of the symbiont AHE12 further complemented the phenotypic characterizations. The hybrid genome assembly of AHE12 yielded a complete finding of elite genes involved in growth-promoting activities, especially IAA production and transportation. The study provides clear insights into the importance of Himalayan medicinal plant-associated bacterial symbionts.

Drying is a crucial post-harvest process for preserving medicinal and aromatic plants like Salvia officinalis (sage), ensuring their availability for various applications, including food, pharmaceuticals, and herbal medicine. This study investigates the effects of two innovative pretreatments—ultrasound (US) and ethanol (ET)—on the drying kinetics and quality attributes of Salvia officinalis leaves. The samples were pretreated with ultrasound (15 min) or ethanol immersion (75% ET, 10 min) before hot air (HA) drying at 40, 50, and 60 °C. The results showed that both pretreatments significantly enhanced drying efficiency. Drying time was reduced by 14.7–22.2% with ultrasound and 35.2–44.4% with ethanol, compared to untreated samples. Effective moisture diffusivity (D_eff) values ranged from 1.87 × 10⁻⁹ to 6.98 × 10⁻⁹ m²/s for untreated samples, while ultrasound and ethanol pretreatments increased D_eff to 2.61 × 10⁻⁹–1.47 × 10⁻⁸ m²/s and 5.22 × 10⁻⁹–2.17 × 10⁻⁸ m²/s, respectively. Specific energy consumption (TEC_t) decreased significantly by 21.5–42% with ultrasound and 40.1–56.27% with ethanol. In addition, increasing the temperature reduced the drying time and energy. In terms of quality attributes, ethanol pretreatment resulted in the highest rehydration ratio (2.46–3.80), while ultrasound-preserved samples exhibited superior retention of bioactive compounds. Antioxidant activity (AXA) in dried samples was highest with ultrasound pretreatment (74.98% at 50 °C), compared to untreated (68.01%) and ethanol-pretreated (60.01%) samples. Total phenolic content (TPC) and total flavonoid content (TFC) were best retained with ultrasound, with values ranging from 5.8 to 20% (TPC) and 7.5–22.2% (TFC) higher than the control. All dried samples showed water activity values ​below 0.5. Higher temperatures and ethanol pretreatment recorded the highest color changes. These findings indicate that ultrasound is more effective in preserving bioactive compounds, while ethanol pretreatment is more efficient in reducing drying time and energy consumption. The combination of both methods may offer an optimized drying approach for Salvia officinalis. 

The study aimed to assess the effectiveness of TiO₂/ZnO nanocomposite-modified biochar (TZB) derived from pristine biochar (TBC) precursor materials to sequester acetaminophen (APH) from the aqueous solution using the batch adsorption technique. The uptake of APH by TZB and TBC was examined at solution pH 7, 30 mg adsorbent dose, and a 100-min contact time. The findings suggest a bimolecular interaction between the adsorbates and adsorbents, with pseudo-second-order kinetics. According to isotherm research, Langmuir and Freundlich models, respectively, best fit the data acquired for TZB and TBC. For both TBC and TZB, an increase in the Langmuir monolayer adsorption parameters was observed, suggesting better sorption of acetaminophen with increasing solution temperature. According to thermodynamic studies, both adsorbents spontaneously removed acetaminophen. Acetaminophen elimination by TBC and TZB was an endothermic procedure. This study validates the prospective use of TBC and TZB as potential capacity substitutes for treating pharmaceutical-polluted wastewater.

This study explores the potential of activated carbons (ACs) derived from invasive Crofton weed biomass for bisphenol A (BPA) removal from aqueous solutions. Chemical activation using ZnCl₂ and H₃PO₄ produced ACs with distinct surface properties. ZnCl₂-activated carbon (ZCWAC100) exhibited the highest specific surface area (1374 m²⋅g⁻¹) and adsorption capacity (315.6 mg⋅g⁻¹), followed by H₃PO₄-activated carbon (HCWAC10) and commercial Darco G-60 (220.3 mg⋅g⁻¹). Adsorption kinetics were well described by pseudo-second-order models, with HCWAC10 achieving equilibrium within 120 min due to its wider pores, while ZCWAC100 followed a dual mechanism of intra-particle and film diffusion. Adsorption isotherms best fitted the Sips and dual-site Langmuir models. BPA removal efficiency decreased in real wastewater due to competition from organic and inorganic constituents, yet ZCWAC100 maintained the highest performance. This work highlights the dual benefits of repurposing invasive plant biomass into cost-effective ACs for sustainable water treatment solutions.