Solvent Extraction Research Articles

A Study on the Treatment of Sodium Sulfate Waste Solution by Constant Current Control Bipolar Membrane Electrodialysis

As environmental pollution has intensified, the importance of recycling spent lithium-ion batteries (LIBs) has significantly increased. Valuable metals contained in LIBs are typically recovered through processes such as leaching, precipitation, and solvent extraction. However, these recycling processes require large amounts of sulfuric acid and caustic soda, resulting in the generation of significant volumes of Na<sub>2</sub>SO<sub>4</sub> waste solution. In order to solve this problem, recent research has focused on using bipolar membrane electrodialysis (BMED) technology to split Na<sub>2</sub>SO<sub>4</sub> and simultaneously recover H<sub>2</sub>SO<sub>4</sub> and NaOH. This study investigated the process of recovering H<sub>2</sub>SO<sub>4</sub> and NaOH from Na<sub>2</sub>SO<sub>4</sub> solution using BMED in a threecompartment cell under constant current conditions. The study evaluated the effects of current density, initial Na<sub>2</sub>SO<sub>4</sub> concentration, and initial H<sub>2</sub>SO<sub>4</sub> and NaOH concentrations. Recovery of H<sub>2</sub>SO<sub>4</sub> and NaOH, current efficiency, energy consumption, and process time were analyzed to determine optimal conditions. Under optimal conditions (1.30 M Na<sub>2</sub>SO<sub>4</sub> solution at 360 A/m²), the recovery of H<sub>2</sub>SO<sub>4</sub> and NaOH were 77.35% and 75.18%, respectively. Energy consumption was 1.43 kWh/kg, with current efficiencies for the acid and base of 51.1% and 49.7%, respectively.

Facile and versatile PDMS-glass capillary double emulsion formation device coupled with rapid purification toward microfluidic giant liposome generation

The exceptional ability of liposomes to mimic a cellular lipid membrane makes them invaluable tools in biomembrane studies and bottom-up synthetic biology. Microfluidics provides a promising toolkit for creating giant liposomes in a controlled manner. Nevertheless, challenges associated with the microfluidic formation of double emulsions, as precursors to giant liposomes, limit the full exploration of this potential. In this study, we propose a PDMS-glass capillary hybrid device as a facile and versatile tool for the formation of double emulsions which not only eliminates the need for selective surface treatment, a well-known problem with PDMS formation chips, but also provides fabrication simplicity and reusability compared to the glass-capillary formation chips. These advantages make the presented device a versatile tool for forming double emulsions with varying sizes (spanning two orders of magnitude in diameter), shell thickness, number of compartments, and choice of solvents. We achieved robust thin shell double emulsion formation by operating the hybrid chip in double dripping mode without performing hydrophilic/phobic treatment a priori. In addition, as an alternative to the conventional, time-consuming density-based separation method, a tandem separation chip is developed to deliver double emulsions free of any oil droplet contamination in a continuous and rapid manner without any need for operator handling. The applicability of the device was demonstrated by forming giant liposomes using the solvent extraction method. This easy-to-replicate, flexible, and reliable microfluidic platform for the formation and separation of double emulsion templates paves the way for the high-throughput microfluidic generation of giant liposomes and synthetic cells, opening exciting avenues for biomimetic research.The presented giant liposome assembly line features a novel treatment-free hybrid chip for double emulsion formation coupled with a high throughput separation chip for sample purification.

Natural acidic deep eutectic solvent-mediated microwave-assisted simultaneous hydrodistillation, hydrolysis, and extraction for obtaining essential oils, gallic acid and ellagic acid from Liquidambar formosana leaves and fruits

In this study, an improved method of naturally acidic deep eutectic solvent-mediated microwave-assisted simultaneous hydrodistillation, hydrolysis, and extraction (MSHDHE) was employed to obtain essential oils, gallic acid and ellagic acid from Liquidambar formosana leaves and fruits. The obtained target analytes were then analyzed via GC‒MS and HPLC. The optimal extraction conditions were identified via a Box–Behnken design. Compared with fruits, L. formosana leaves contain more gallic acid and ellagic acid, which have more essential oils. GC‒MS analysis revealed few variations in the composition and content of L. formosana leaves and fruit essential oils. A total of 36 components in the essential oil of L. formosana leaves and 55 components in the essential oil of the fruits were detected via GC‒MS. Compared with classical hydrodistillation and microwave-assisted hydrodistillation, natural acidic deep eutectic solvents outperform conventional extraction solvents (pure water), providing a scientific foundation for the extraction of natural acid deep eutectic solvents consisting of choline chloride and natural organic acids.

The effects of sample preparation on the interpretation of pyrolysis-based organic matter analysis in immature oil shale

Oil shale as well as shale oil and shale gas are significant energy resources with huge reserves present in different parts of the world. Various geochemical proxies have been applied to assess the petroleum potential of oil shales with samples pre-treated in various ways, e.g. as whole rock or demineralized sample or as solvent extracted rock/kerogen. In this respect, it is important to understand and quantify, how achieved geochemical parameters are influenced by pre-treatment. In this study, a systematic comparison is presented based on a study on i) whole rock, ii) extracted whole rock, iii) kerogen concentrate, and iv) extracted kerogen concentrate obtained after solvent extraction of demineralized shales. In total, seven immature, organic matter-rich samples from the Miocene lacustrine sediments of the Nördlinger Ries impact crater, Germany, were pretreated in this way leading to overall 28 samples. A set of elemental analysis (C, H, N), Rock-Eval pyrolysis, and Curie Point-pyrolysis–gas chromatography–mass spectrometry measurements were performed on these pretreated samples. Mineral matter removal leads to significant increase of total organic carbon, but also thermally evaporable and pyrolytically cracked organic matter (Rock-Eval S1 and S2 peaks). To some extent, labile organic matter represented in the original S2 peak can be destructed by mineral removal with hydrochloric and hydrofluoric acid, as shown by elevated values of PI [S1/(S1 + S2)] after demineralization. The organic matter type tends to be more petroleum-prone with raised hydrogen index (HI) and aliphaticity values after demineralization, while Rock-Eval Tmax values commonly applied as parameters for thermal maturity tend to decrease, though not for all samples.Reduced TOC, S1, S2 and PI values of extracted samples suggest that both thermally evaporable and additionally some non-evaporable but soluble organic matter hidden in the original S2 peak can be lost after solvent extraction. Increased values of HI, H/C and N/C of extracted samples indicate more oil-prone organic matter types than unextracted samples. Typical maturity-related parameters such as aliphaticity and Rock-Eval Tmax decrease. Smectite and zeolites, which are abundant in the samples, are suggested to protect organic matter to some extent against solvent extraction, influencing a variety of geochemical proxies and the occurrence of metal cation-containing minerals. Zeolite invigorates the protection effect.

A Descriptive Analysis of the Nutraceutical Constituents, Extraction Techniques, and Possible Health Benefits of Tamarind

Background: Tamarind is a multifunctional tree, with nearly every portion having significant nutritional or therapeutic use. The fruit, which produces acidic pulp, is the most valuable and often utilized portion. Objective: The aim of this paper is to discuss the distribution, habitat, chemical constituents and extraction techniques of tamarind. Methods: This study reviews the chemical constituents, health benefits and extraction techniques of tamarind. Databases such as PubMed, Scopus, Science Direct, and Google Scholar were used to search articles from 1990 to 2022. The key search terms included tamarind, phytoconstituents extraction and anti-nutritional factor. Research studies also included similar plant parts extracted from similar solvents which were considered in this review. Results: According to our observations, Tamarindus indica is a crucial plant with significant pharmacological properties. It is extensively used as a conventional medicine to treat a variety of disorders; however, its active ingredients require further investigation for future drug development and pharmacological activity. Tamarind contains a diverse range of bioactive compounds, including polyphenols, flavonoids, alkaloids, vitamins, and minerals, which have been associated with various health-promoting properties. The study examines different extraction methods used to isolate tamarind's bioactive constituents, such as solvent extraction, supercritical fluid extraction (SFE), and microwave-assisted extraction (MAE). Furthermore, the research highlights the potential health benefits of tamarind, including antioxidant activity, anti-inflammatory effects, gastrointestinal support, cardiovascular benefits, and antimicrobial properties. Discussion: Tamarind includes citric acid, linoleic acid, volatile oils, vitamin C, potassium, Camp sterol, -amyrin, Tannins, saponins, and glycosides as a result of this. It has several pharmacological properties such as reducing swelling, preventing oxidation, hypolipidemic, weight loss, antibacterial, hepatoprotective, anthelmintic, and painkiller properties. These properties will assist to generate interest in Tamarind and develop novel preparations with more medicinal and commercial potential. The findings indicate that tamarind holds significant promise as a natural resource for developing functional foods, nutraceuticals, and pharmaceuticals with potential positive impacts on human health.

Chitosan extracted from the feather of Dosidicus gigas crosslinked with glutaraldehyde for use as a 99Mo adsorbent

The production of Technetium-99 m (99mTc) is important for cancer diagnosis. The solvent extraction is the most widely used method to obtain 99mTc; however, due to the evaporation of the polluting solvent into the environment, a radiochemical separation using a chromatographic column system based on adsorbent materials would be cleaner and more efficient.In this study, squid feather (Dosidicus gigas) chitosan (SFC) polymers have been synthesized and crosslinked with glutaraldehyde solutions at concentrations of 50, 40 and 25 % to study the adsorption of 99Mo with the aim of test a promising material to produce 99mTc in the chromatographic column of the 99Mo/99mTc generator. Likewise, the same methodology of synthesis was performed using a commercial chitosan (CC) as a control. Deacetylation degree was measured obtaining 74.15 % and 77.65 % for the SFC and CC polymers, respectively. The molecular weight obtained was 990.72 kDa for SFC and 722.72 kDa for CC and the characterization of the biopolymers was performed with FTIR, SEM, XRD, TGA y FT Raman techniques. Equilibrium time, adsorbent mass and pH effect were evaluated as factors that influence the adsorption process of 99MoO4-2. The zero load point (pHPZC) analysis confirmed the positive charge of the crosslinked polymers, improving the adsorption capacity of 99MoO4-2 at low pH values between 2 and 4, following a pseudo-first order model. With respect to the adsorption isotherms, they exhibit maximum values of 99MoO42- of 482 mg g−1 SFCG40 and 502 mg g−1 CCG25 with a better fit to the Langmuir theoretical model.

The effect of Coix lachrymal L. seed extract on the expression of inflammation and fibrogenesis genes in human retinal pigment epithelial cells.

Proliferative vitreoretinopathy (PVR) is a vision-threatening condition associated with retinal-detachment (RD), primarily caused by fibrocellular scar membrane formation. This study investigates the therapeutic potential of adlay seed extract fractions in mitigating PVR-associated pathways, focusing on oxidative stress, proliferation, inflammation, and fibrogenesis in retinal pigment epithelial (RPE) cells. Adlay seed extract fractions (methanolic: MeOH and residual: Res) were obtained through solvent extraction and characterized for carbohydrate, protein, flavonoid content, and antioxidant activity. RPE cells were cultured, and their viability in response to adlay fractions was assessed using the MTT assay. Gene expression analysis of IL-1β, IL-6, LIF, TGF-β, Snail and α-SMA genes was conducted via real-time PCR after treatment with adlay fractions. The Res fraction exhibited higher levels of protein, carbohydrate, flavonoids, and phenols compared to the MeOH fraction, along with significantly enhanced antioxidant activity. Both fractions showed inhibitory effects on RPE cell viability, with the Res fraction demonstrating a more pronounced impact. Gene expression analysis revealed a significant decrease in IL-6 and TGF-β expression with the MeOH fraction treatment, while the Res fraction led to decreased expression of IL-6, LIF, TGF-β, Snail and α-SMA, indicating a more comprehensive modulation of PVR-associated pathways. This study highlights the potential therapeutic benefits of adlay seed extract fractions in mitigating PVR-associated pathways in RPE cells. The Res fraction, particularly rich in bioactive compounds and exhibiting potent antioxidant activity, shows promise in attenuating oxidative stress, proliferation, inflammation, and fibrogenesis, critical processes in PVR development. These findings underscore the potential of adlay seed extracts as a novel therapeutic strategy for PVR warranting further investigation and clinical validation.

Comparison of extraction process, physicochemical properties, and in vitro digestion characteristics of chia seed mucilage polysaccharide.

The study explored five (acidic, alkaline, heating, ionic liquid, and urea solvent) extraction methods' effects on chia seed mucilage polysaccharide (CSM), an anionic polymeric macromolecule, regarding its physicochemical properties, structure, and digestion behavior. The results showed that extraction parameters have a considerable effect on modulating CSM properties. Significant differences emerged in the predominant chemical compositions: the carbohydrates and protein content ranged from 49.20±0.06% to 85.81±0.03%, and 3.20±0.13% to 14.57±0.30%, respectively. The structural analysis revealed that alkaline heating treatment facilitated the formation of protein-polysaccharide conjugates, resulting in reduced particle size, enhanced ζ-potential, and improved thermal stability (194.72±2.19J/g). The crystallinity of CSM varied, peaking at 42.9±0.22% without pH adjustment and heating. CSM extracted using 6M urea exhibited the lowest protein content, and crystallinity (25.50±0.09%), coupled with the highest gastrointestinal digestion rate and poorest thermal stability (with a carbohydrate degradability of 24.223±1.78% and enthalpy value of 62.82±0.32J/g). The CSM obtained under alkaline heating showed minute particles (201.1±10.35μm), the highest ζ-potential absolute value (20.95±2.28mV), and robust thermal stability (194.72±2.19J/g of enthalpy value), which is ideal for stabilizing emulsions or encapsulating thermolabile substances. Additionally, compared to monovalent cations‑sodium ions, divalent cations‑magnesium ions, is more tend to aggregate the CSM structure, resulting in larger molecular particles and a higher protein content. Elevated ionic concentration further diminished thermal stability. These findings suggest that CSM is a customizable, multi-purpose polymer that can be extracted in various ways based on the end-product requirements.

Redefining the waste: Sustainable management of olive mill waste for the recovery of phenolic compounds and organic acids

The olive oil industry generates significant amounts of olive mill waste (OMW), which poses environmental challenges due to its high organic load and phenolic content. This study investigates an eco-friendly approach to managing OMW by recovering valuable phenolic compounds (PCs) and volatile fatty acids (VFAs) through an integrated process. The methodology involves a filter press, followed by a self-cleaning mechanical vapor recompression (SCMVR) process for water and volatile compounds separation, and a subsequent liquid-liquid extraction for PCs. 99 % of the VFAs were recovered as organic acid salts from the SCMVR distillate and characterized using X-Ray diffraction (XRD) analysis. The Box-Behnken design (BBD) of response surface methodology (RSM) was used to optimize the extraction process, considering variables such as solvent type, pH, temperature, and extraction time. The liquid-liquid extraction process yielded a 98 % recovery of PCs with two-stage extraction process, including key phenolic species such as vanillic acid, caffeic acid, oleuropein, coumaric acid and gallic acid, identified by LC-MS/MS. This study highlights the potential for converting olive mill waste into valuable resources, promoting sustainable practices, and supporting a circular economy in the olive oil industry.

Optimization of Microwave-Assisted Polyphenol Extraction and Antioxidant Activity from Papaya Peel Using Response Surface Methodology and Artificial Neural Network

The objective of the present study is to determine the optimal conditions of microwave-assisted extraction (MAE) such as microwave power (MWP), irradiation time (I-time), ethanol concentration (EtOH%), and solvent-to-solid ratio (S/S) for maximizing total polyphenol content (TPC) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity from papaya peel. Box-Behnken design (BBD) was used considering MWP 300–600 W, I-time 60-120 s, EtOH% 30-70%, and S/S 30-70 mL/g. Additionally, response surface methodology (RSM) and artificial neural networks (ANN) were employed for modelling, with cross-validation to enhance reliability. These models were combined with the desirability function (DF) and/or genetic algorithm (GA) optimization approaches. Maximizing TPC and DPPH activity while maintaining MWP, I-time, EtOH%, and S/S within their respective ranges using hybrid optimization approaches (RSM-DF: TPC = 1058 mgGAE/100g, and DPPH = 83%, RSM-GA: TPC = 1064 mgGAE/100g and DPPH = 79%, and ANN-GA: TPC = 1086 mgGAE/100g, and DPPH = 83%,) yielded consistent optimal results. An additional optimization approach (RSM-DF: TPC = 955 mgGAE/100g, and DPPH = 90%), aimed at minimizing MWP, I-time, EtOH%, and S/S while maximizing TPC and DPPH activity, showed a significant reduction of approximately 3 L in ethanol consumption for each 100 g of dry samples. The maximized TPC and DPPH activity in all four approaches showed a significant (p < 0.05) alignment with their corresponding validation tests, demonstrating the better performance of these modelling and optimization processes. In terms of assessing the effectiveness of microwave assistance, conventional solvent extraction was also performed, maintaining a 70 mL/g S/S ratio of 55% ethanol at 60°C for 2 h. This method resulted in lower values of TPC (857 ± 23 g GAE/100g) yield and DPPH activity (72 ± 5%) compared to the optimized condition of MAE.

Deep-eutectic solvent extraction of ginsenosides and ginseng polysaccharides from ginseng residue and utilization of post-extraction residue

Deep-eutectic solvent extraction of ginsenosides and ginseng polysaccharides from ginseng residue and utilization of post-extraction residue

Efficient Removal of Lipophilic Compounds from Sewage Sludge: Comparative Evaluation of Solvent Extraction Techniques

Municipal sewage sludge, a by-product of wastewater treatment plants, presents environmental challenges due to its complex composition. Particular concern is the lipophilic and aliphatic compounds that pose risks to the environment and human health. This study focuses on the efficient removal of those compounds from sewage sludge using several organic solvents (hexane, toluene, chloroform, dichloromethane, acetone, hexane-methanol mixture, ethanol, and methanol) and ionic liquids (ILs) like tetrakis(hydroxymethyl)phosphonium chloride and 1-ethyl-3-methylimidazolium acetate by solvent extraction techniques. To determine optimal conditions, various factors such as solvent types, contact time, and temperature were examined. The results reveal that solvent polarity significantly impacts extract composition, with non-polar solvents like hexane and toluene yielding profiles characteristic of lipid-type compounds. An in-depth analysis of contaminants present in the sewage sludge was studied by Fourier-transform infrared spectroscopy (FTIR). Additionally, nuclear magnetic resonance (NMR) was used to identify the extracted compounds, including triglycerides, aliphatic esters, aliphatic alcohols, and free carboxylic acids. NMR provides data on the composition of the sewage sludge and indicates that among all the solvents used, tetrakis(hydroxymethyl) phosphonium chloride was the most suitable solvent for removing lipophilic and aliphatic compounds. Regeneration potential and reusability of the IL were conducted and verified by NMR. The results showed that tetrakis(hydroxymethyl) phosphonium chloride ionic liquid could be used for several extraction cycles. Identifying these compounds in the extracted mixture demonstrates that it adds value and potential for various applications. Towards environmental sustainability and circular economy, this effort develops strategies for the safe management, disposal, and recyclability of sewage sludge and, the reduction in environmental and health hazards associated with organic compounds.

Bioremediation of Pharmaceutical Wastewater using Oscillatoria subsalsa and Oscillatoria flos-aquae: Efficiency in Contaminant Removal, Phytochemical Analysis and Antibacterial Activity against Biofilm-Forming Bacteria

This study investigates the potential of cyanobacteria, specifically Oscillatoria subsalsa and Oscillatoria flos-aquae, for the bioremediation of pharmaceutical wastewater and their effectiveness in eliminating biofilm forming, multidrug-resistant bacteria. Cyanobacteria species were collected from the Mandapam coast in India and analyzed for their ability to treat pharmaceutical effluents. Phytochemical compounds in solvent extracts were assessed prior to remediation. The cyanobacteria were evaluated for their effectiveness in reducing pH, biochemical oxygen demand (BOD), chemical oxygen demand (COD), ammonia, nitrite, nitrate and phosphate levels in wastewater. Antibacterial activity was analyzed against biofilm-forming bacterial isolates from pharmaceutical effluents. Both O. subsalsa and O. flos-aquae demonstrated significant reductions in environmental contaminants. O. subsalsa was more effective in reducing COD, while O. flos-aquae excelled in reducing nitrate and nitrite levels. Phytochemical analysis revealed the presence of alkaloids, carbohydrates, flavonoids, phenols, saponins, tannins, terpenoids, sterols and quinones, indicating a rich profile of bioactive compounds. The antibacterial tests showed that both cyanobacterial species had significant antibacterial properties, with O. flos-aquae displaying stronger and more consistent activity, particularly against Gram-negative bacteria. The study highlights the potential of O. subsalsa and O. flos-aquae in wastewater treatment and their capability to combat multidrug-resistant pathogens. These findings suggest that cyanobacteria offer a promising, sustainable approach for effective bioremediation and management of pharmaceutical wastewater.

Varying extractability of petrogenic and pyrogenic polycyclic aromatic hydrocarbons (PAH) in urban soils: Evaluation of sample preparation and extraction of 71 PAH and alkylated PAH

PAH extraction methods have been widely studied over the last decades. However, there is still no consistent method for contaminated soils. Here, for the first time, PAH source characteristics in soils were considered for the investigation of different pretreatment methods, extraction techniques and solvents in nine petrogenic to primarily pyrogenic urban soils. Sources were identified by macroscopic identification of source substrates and analysis of 71 PAH and alkylation patterns.The comparison of extraction solvents revealed that a combined sequential extraction using dichloromethane (for petrogenic PAH) and toluene:methanol (6:1) led to the highest extraction efficiencies for all samples and is therefore best suited for PAH analysis of unknown samples. Acetone:n-hexane led to the lowest extraction efficiencies for all samples and is not recommended as extraction solvent. The comparison of extraction techniques showed that Pressurized Solvent Extraction is more efficient than ultrasonic extraction especially for petrogenic PAH, but also for pyrogenic PAH. Grinding increased PAH extractability considerably but mainly for petrogenic PAH from bituminous coal particles. In mixed to primarily pyrogenic samples with a smaller proportion of coal, the enhanced extractability of coal leads to a more petrogenic PAH distribution and consequently a decrease in the source identifying PAH Alkylation Index.It is concluded that PAH contents in unknown (urban) soils, where pyrogenic and petrogenic PAH can be present, cannot generally be compared if different extraction techniques, different extraction solvents and grinding or no grinding are applied. As extraction efficiency increases with more effective methods and solvents for bituminous coals, it is recommended to define a specific extraction technique and solvent mixture for improved comparability in future PAH analyses.

Potentialities of semi-continuous anaerobic digestion for mitigating antibiotics in sludge.

The behavior and removal of roxithromycin (ROX), oxytetracycline (OTC), chlortetracycline (CTC), and enrofloxacin (ENR) were investigated during the steady state of sludge anaerobic digestion (AD) in semi-continuous mode (37°C). Sludge was spiked at realistic concentrations (50μg/L of each antibiotic) and then used to feed the bioreactor for 80days. Antibiotics were extracted from the substrate and digested sludge samples by accelerated solvent extraction (ASE). Accurate determination of antibiotics was obtained by the standard addition method (SAM) associated with the liquid chromatography-tandem mass spectrometry (LC-MS/MS). The presence of antibiotics at a concentration of 2.5μg/g TS had no inhibitory effects on methane (CH4) production, total and volatile solids (TS and VS) removal as well as chemical oxygen demand (COD) removal. During the steady-state, antibiotics were removed significantly by 50, 100, and 59% respectively for the ROX, OTC, and CTC. Furthermore, ENR removal was not statistically significant and was estimated at 36%. This study highlighted that AD process could partially remove parent compounds, but ROX, CTC, and ENR persisted in the digested sludge. Hence, AD could be considered as a sludge treatment for mitigating, but not suppressing, the release of antibiotics through sludge application.

Fractionating the Flavonoids in Lonicerae japonicae Flos and Lonicerae flos via Solvent Extraction Coupled with Automated Solid-Phase Extraction

Due to the structural diversity of flavonoids in functional plant foods and the inherent limitations of existing techniques, it is important to develop a simple and green (environmentally friendly) method of extracting flavonoids from plant foods. In this study, a method involving solvent extraction followed by automated solid-phase extraction was developed for extracting flavonoids from Lonicerae japonicae flos (JYH) and Lonicerae flos (SYH), both of which are widely used functional plant-based foods in Asian countries. For the optimisation of the solvent extraction method, solvent concentration (0.0, 20.0, 40.0, 60.0, 80.0 and 100.0% (v/v) of ethanol–water solution), extraction temperature (40, 60 and 80 °C) and extraction time (15.0, 30.0, 60.0, 90.0 and 120.0 min) were evaluated via design of experiment after screening. For solid-phase extraction, five cartridges (Strata-X, InertSep RP-2, InertSep RP-C18, Bond Elut-ENV, Oasis Prime HLB) were evaluated and different elution steps were optimised to obtain high recoveries (79.69–140.67%) for eight target flavonoids, including rutin, isoquercetin and luteolin. Antioxidant capacity assays revealed that JYH samples demonstrated superior antioxidant potential compared to SYH. The optimised extraction method provides a valuable tool for industrial-scale flavonoid production.

Innovative synergistic extraction of copper(II) from sulfate solutions using D2EHPA and Tri-n-octylphosphine oxide

Solvent extraction is a critical process in the copper extraction industry, offering an advanced method for separating and purifying copper from its ores. As industries aim for increased efficiency and sustainability, the significance of enhancing copper extraction methods is increasingly evident. The liquid-liquid extraction of copper(II) from sulphate medium with di(2-ethylhexy1) phosphoric acid (D2EHPA, HL) has been investigated in chloroform and 1-octanol at 25°C. The study examined the impact on several factors, including the equilibrium pH, extractant concentration, and the nature of diluent. The extracted copper(II) species were found to be CuL2.2HL in chloroform and CuL2 in 1-octanol and the extraction constants of these species were also estimated. The effect of the presence of tri-n-octyl phosphine oxide (TOPO) on the above extraction systems was also studied. A strong antagonistic effect observed during the extraction of copper(II), in the chloroform system is caused by a D2EHPA–TOPO interaction. In the 1-octanol system, the presence of TOPO may change the reaction stoichiometry of copper(II) and D2EHPA.

Environmental insights of bioethanol production and phenolic compounds extraction from apple pomace-based biorefinery

Food waste is one of the main challenges of solid waste management throughout the food supply chain. Apples are one of the most widely consumed fruits worldwide, the production of which is accompanied by the generation of pomace as a by-product with valuable nutrients. This research presents the first environmental insights of a multiproduct apple pomace-based biorefinery through a life cycle perspective. The design and process modelling of this platform aims to produce bioethanol and extract total phenolic compounds (TPC) towards an efficient use of the pomace obtained from the apple manufacturing industry (juice production). Bioethanol production consist of pressing, fermentation, distillation as the main processes; while in the case of TPC, two extraction techniques were evaluated: i) solvent extraction (mainly water), and ii) the Soxhlet method. The life cycle analysis followed an attributional cradle-to-gate approach considering different midpoint impact categories from the ReCipe 2016 method such as Global Warming (GW), Eutrophication, Human Toxicity, Fossil Scarcity, among others. The results indicate that bioethanol production encompasses a GW profile of 3.17 kg of CO2 eq per kg of product, being the vinasse treatment (subproduct after distillation) the most impactful stage. Phenolic compounds extraction with water achieves a total value of 5.8 kg CO2 eq per g of TPC, while 0.22 kg CO2 eq per g of TPC is obtained with Soxhlet technique. Furthermore, a sensitivity analysis is addressed to improve the environmental profile of bioethanol and TPC. This research demonstrated the relevance of process design on the environmental performance of bioethanol and TPC, where stillage treatment has a key contribution to the results and the use of solvents in TPC extraction, although improving extraction yield, leads to a higher environmental impact.

Recovery of Metals from Titanium Ore Using Solvent Extraction Process: Part 1—Transition Metals

Recovery of Metals from Titanium Ore Using Solvent Extraction Process: Part 1—Transition Metals

Harnessing the past: Vibration analysis of organic additives in ancient plasters for sustainable building solutions

This study investigates plant-based organic additives and grains used in ancient earthen plasters from the caves of Karla, Bhaja, Pitalkhora, Ellora, and Aurangabad in Maharashtra, India, highlighting their relevance for sustainable modern construction. Stereo microscopy, FTIR spectrophotometry, and phytochemical analysis identified rice husk, millet, wheat, Chenopodium album, Paspalum, barnyard millet, foxtail millet, and Fumaria seeds as key organic components. Starch grain analysis confirmed the presence of wheat, millet, and mung bean starches, while polarized light microscopy revealed distinctive birefringence patterns, such as the Maltese cross. FTIR analysis of solvent extractions identified natural compounds, including starches, gums, proteins, oils, waxes, and tree resins. These organic additives, especially rice husk, prevalent in Karla, Bhaja, and Pitalkhora samples, and the balanced composition of hemp fibers, seeds, and gums in Ellora samples, contributed significantly to the strength and durability of the plasters. The use of beeswax and tree resins as natural binders further underscores the ingenuity of these ancient techniques. This research not only highlights the botanical diversity in ancient construction but also draws critical connections to modern sustainable practices. The carbon-negative potential of these materials, combined with their renewability and resilience, aligns closely with contemporary green building strategies, offering inspiration for eco-friendly construction rooted in traditional Indian architecture.