Quantitative assessment of poly- and perfluoroalkyl substances (PFASs) in aqueous film forming foam (AFFF)-impacted soils: a comparison of analytical protocols.

Quantitatively assessing all per- and poly fluoroalkyl substances (PFASs) in an environmental sample, particularly soils impacted by aqueous film forming foams (AFFFs), has proven to be a challenge. To make such an assessment, a comprehensive sample processing procedure and analytical tool must be used. However, doubts remain whether current analytical tools such as high-resolution mass spectrometry (HRMS) with targeted quantitation and semi-quantitative analysis of suspects (Semi-Q HRMS) or total organic fluorine (TOF) are capable of accurately quantifying all non-polymeric PFASs in a sample. Further, current comprehensive soil PFAS HRMS methods are incompatible with TOF, preventing direct comparisons of the approaches. To enable direct comparisons, a soil sample processing procedure that is comprehensive as well as compatible with multiple analytical tools is needed. In this study, we assessed the performance of a previously developed soil PFAS method, EPA Method 1633, and a hybrid solid phase extraction (SPE)-based method for characterizing AFFF-impacted soil composites while maintaining compatibility with multiple analytical tools (i.e., Semi-Q HRMS and TOF). Comparative results for AFFF-impacted soil composites indicate analysis via EPA Method 1633 (as compared to the novel hybrid method) results in maybe up to 75% of the PFAS mass being missed by only analyzing for compounds listed in EPA Method 1633. Simply expanding the EPA Method 1633 analyte list was insufficient to account for the missing mass: up to 69% of the PFAS mass was still missed because of EPA Method 1633's extraction and cleanup bias. Additionally, the novel method developed offers a more comprehensive analysis with minimal reductions to sensitivity when compared to those reported in EPA Method 1633, with limits of quantification ranging from 0.12 to 2.4 ng/g as compared to 0.16-4.0 ng/g, respectively. For these reasons, an alternative hybrid SPE-based method is proposed for comprehensive evaluation of PFASs in AFFF-impacted soils.

Efficient Extraction and Separation of Scandium from Scandium-Bearing Solid Waste and Acid by Synergistically Leaching Followed by Solvent Extraction.

The solid waste and waste acid generated during the production of titanium dioxide contain considerable amount of scandium, which are valuable secondary resources. In this study, the titanium dioxide waste acid was used to leach the scandium-containing solid waste, and the leached solution was pretreated for iron removal by reduction-crystallization process. After that, scandium was recovered from the leached solution by using the P204-TBP co-extraction system. The process parameters were investigated systematically. The results showed that iron powder reduction-crystallization for iron removal at molar ratio of Fe:Fe3+ = 0.25 was most suitable for subsequent extraction, and the scandium extraction efficiency could reach 100% using 15% P204-5% TBP at 25 °C with A/O = 8. This study provided a novel process for treating scandium-bearing solid waste with scandium-bearing waste acid, showing great potential for industrial application.

A Comprehensive Review on Deep Eutectic Solvents: Their Current Status and Potential for Extracting Active Compounds from Adaptogenic Plants.

Deep eutectic solvents (DESs) have attracted attention from researchers as novel compounds for extracting active substances because of their negligible toxicity, polarity, and ability to be tailored depending on the experiment. In this review, we discuss deep eutectic solvents as a promising medium for the extraction of adaptogenic compounds. In comparison to traditional methods, extraction with the use of DESs is a great alternative to the excessive usage of harmful organic solvents. It can be conducted in mild conditions, and DESs can be designed with different precursors, enhancing their versatility. Adaptogenic herbs have a long medicinal history, especially in Eastern Asia. They exhibit unique properties through the active compounds in their structures, including saponins, flavonoids, polysaccharides, and alkaloids. Therefore, they demonstrate a wide range of pharmaceutical effects, such as anti-inflammatory, antibacterial, and anticancer abilities. Since ancient times, many different adaptogenic herbs have been discovered and are well known, including Panax ginseng, Scutellaria baicalensis, and Schisandra chinensis. Active compounds can be extracted using standard methods, such as hydrolyzation, maceration, and conventional reflux extraction. However, due to the limitations of classical processing technologies, there has been a need to develop new and eco-friendly methods. We focus on the types of solvents, extraction efficiency, properties, and applications of the obtained active compounds. This review highlights the potential of DESs as eco-friendly alternatives for extracting bioactive compounds.

Comparative study of bisphenols in e-cigarette liquids: Evaluating fabric phase sorptive extraction, ultrasound-assisted membrane extraction, and solid phase extraction techniques.

To address the under-researched risk of bisphenols (BPs) in e-cigarette liquids, comprehensive studies have been conducted to propose optimum sample preparation and analysis methods. To determine twelve BPs in refill liquids for e-cigarettes, three sample preparation methods based on distinct operational and working principles were employed. These included fabric phase sorptive extraction (FPSE), ultrasound-assisted solvent extraction of porous membrane-packed samples (UASE-PMS) and solid phase extraction (SPE) utilizing molecularly imprinted polymers (MIPs) technology. Each extraction method was combined with ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS). Key parameters of FPSE and UASE-PMS procedures were optimized. This optimization included selection of the FPSE membrane types, durations of extraction and the choice solvents. Comprehensive validation was conducted, demonstrating linearity across a range from 2 to 60 ng/mL for all BPs (BPS, BPA, BPF, BPE, BPB, BPC, BPZ, BPFL, BPBP, BPP, BPG and BPM). Determination coefficients were above 0.9913, signifying linear relationship. The limits of detection (LODs) were established below 0.90 ng/mL, while the limits of quantification (LOQs) were lower than 2.5 ng/mL. Notably, the method based on UASE-PMS was successfully applied to the analysis of refill liquids for e-cigarettes samples. A comparative analysis of the methods highlighted variances in precision, accuracy, and applicable aspects, such as adjustment of parameters, sample preparation time, cost, handling, availability and possible limitations. Three methods have been identified as suitable for analysing BPs in e-cigarette refill liquids, highlighting the necessity to examine their presence in these products.

In vitro antidiabetic and antioxidant activities of Galega officinalis extracts.

The purpose of the present study was to determine the total phenolic, flavonoid, and galegine content and antioxidant activity, as well as the in vitro antidiabetic potential of different extracts of Galega officinalis using the solvent extraction method. The results demonstrated that the highest yield of extraction (28.05%) and galegine content (17.40 ± 0.04 µg/g of sample) was obtained using water as the solvent (p < .05). However, the highest total phenolic content (TPC) (138.35 ± 0.63 mg GAE per gram of dried GOEs) and total flavonoid content (TFC) (189.12 ± 1.47 mg catechin per gram of dried GOEs) were extracted using A90 (acetone-water, 90:10) solvent. A90 extract exhibited the highest inhibition of sucrase activity (91.42%) (p < .05). Also, the inhibitory activity of A90 against α-amylase (59.96%), α-glucosidase (54.3%), and maltase (62.73%) was significantly higher than that of A70 (acetone-water, 70:30) and E20 (ethanol-water, 20:80) (p < .05). According to antioxidant activity results, the highest ABTS•+ (360.5 ± 15.69 µmol Trolox eq per gram of dried GOEs), hydroxyl radical-scavenging activity (3657.75 ± 21.56 µmol histidine eq per gram of dried GOEs), and FRAP assay (558.18 ± 20.26 µmol FeSO4 eq per gram of dried GOEs) were related to A90, while the best DPPH radical-scavenging activity and metal-chelating activity were related to A70 (302.66 ± 2.42 µmol Trolox equivalents per gram of dried GOEs) and E20 (36.5 ± 1.02 µmol EDTA eq per gram of dried GOEs), respectively. Taken together, A90 appears to be the best solvent to get Galega officinalis extract with the highest antioxidant and antidiabetic activity.

Investigation of solvent extraction of acetic acid and acetone from water in the presence of SiO2 nanoparticles using molecular dynamics simulation.

In this study, molecular dynamics simulation was used to predict the molecular diffusion coefficient of acetic acid and acetone in water, toluene, and benzene. The results showed that COMPASS was the best force field to optimize the atoms and structure of molecules, and the results were compared with experimental equations. The Arrhenius behavior of the molecular diffusion coefficient was investigated at three temperatures. The extraction of acetic acid and acetone from water was investigated using two solvents, toluene, and benzene, with and without SiO2 nanoparticles. The relative concentration change diagram was drawn for three cases without and with SiO2 nanoparticles. To quantitatively examine the results, extraction efficiency, selectivity, and distribution coefficient were calculated. The extraction efficiency of acetone from water by benzene in the absence of silica nanoparticles was 65.748 %, this value in the presence of SiO2 nanoparticles with a concentration of 0.2231 wt% was 72.45 % due to the Brownian motion of the nanoparticles, which increased the mass transfer and as a result, the extraction efficiency. With the further increase of nanoparticles up to 1.7573 wt%, the extraction efficiency decreased to 61.276 %, which can be attributed to the accumulation of silica nanoparticles and the decrease in the free movement of nanoparticles.

Control of encapsulation efficiency and morphology of poly(lactide-co-glycolide) microparticles with a diafiltration-driven solvent extraction process.

The removal of organic solvents during the preparation of biodegradable poly(D,L-lactide-co-glycolide) (PLGA) microparticles by an O/W- solvent extraction/evaporation process was investigated and controlled by diafiltration. Emulsification and steady replacement of the aqueous phase were performed in parallel in a single-vessel setup. During the process, the solidification of the dispersed phase (drug:PLGA:solvent droplets) into microparticles was monitored with video-microscopy and focused beam reflectance measurement (FBRM) and the residual solvent content was analyzed with headspace gas chromatography (organic solvent) and coulometric Karl-Fischer titration (water). Microparticles containing dexamethasone or risperidone were characterized with regard to particle size, morphology, encapsulation efficiency and in-vitro release. Diafiltration-accelerated solvent extraction shortened the process time by accelerating solidification of dispersed phase but reduced the residual dichloromethane content only in combination with increased temperature. Increasing the diafiltration rate increased particle size, porosity, and the encapsulation efficiency of risperidone. The latter effect was particularly evident with increasing lipophilicity of PLGA. A slower and more uniform solidification of end-capped and increased lactide content PLGA grade was identified as the reason for an increased drug leaching. Accelerated solvent extraction by diafiltration did not affect the in-vitro release of risperidone from different PLGA grades. The initial burst release of dexamethasone was increased by diafiltration when encapsulated in concentrations above the percolation threshold. Both porosity and burst release could be reduced by increasing the process temperature during diafiltration. Residual water content was established as an indicator for porosity and correlated with the burst release of dexamethasone.

Exploring macroalgae biorefinery: Extraction of bioactive compounds and production of volatile fatty acids.

Macroalgae have gained significant attention in recent research owing to their potential as novel food source and their noteworthy nutritional properties. However, a substantial amount of these macroalgae accumulates along the coast without being utilized, highlighting the need for proper treatment and disposal methods to mitigate secondary pollution effects. Previous studies on macroalgae have primarily focused on extracting bioactive compounds or anaerobic digestion processes to produce methane or volatile fatty acids (VFA), with observed improvements following different pre-treatments. In this study, three biorefinery options for macroalgae have been compared. Additionally, the extraction of bioactive compounds followed by VFA production is proposed as a promising new valorization strategy. Milled macroalgae exhibited a low methane production yield (138 ± 17 NmL CH4·g volatile solid-1), corresponding to 31 ± 4 % biodegradability, while the acidification percentage was higher (45 ± 1%). Among the three solvents applied (water, ethanol and acetone), ethanol (80%) at 25 °C was the most effective in recovering bioactive compounds, such as chlorophylls, sugars, and phenolic compounds with antioxidant activity. The extraction of chlorophylls and phenolic compounds was not influenced by particle size reduction. However, a more efficient extraction of sugars was observed with lower particle size. Moreover, ethanol treatment demonstrated the good efficiency in VFA production, reaching up to 3.6 ± 0.2 g VFA-(chemical oxygen demand, COD)·L-1, with a VFA spectrum (in COD basis) consisting of 51% acetic acid, 29% propionic acid, 5% i-butyric acid, 7% butyric acid, and 7% i-valeric acid. These findings highlight the potential of ethanol for efficient compound recovery and VFA production from macroalgae.

Quantitative analysis of microplastics in beach sand via low-temperature solvent extraction and thermal degradation: Effects of particle size and sample depth.

Quantifying trace levels of microplastics in complex environmental media remains a challenge. In this study, an approach combining field collection of samples from different depths, sample size fractionation, and plastic quantification via pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) was employed to identify and quantify microplastics at two public beaches along the northeast coast of the U.S. (Salisbury beach, MA and Hampton beach, NH). A simple sampling tool was used to collect beach sand from depth intervals of 0-5 cm and 5-10 cm, respectively. The samples were sieved to give three size fractions: coarse (>1.2 mm), intermediate (100 µm-1.2 mm), and fine (1.2 µm-100 µm) particles. Following density separation and wet peroxide oxidation, a low-temperature solvent extraction protocol involving 2-chlorophenol was used to extract polyester (PET), polystyrene (PS), polyamide (PA), and polyvinyl chloride (PVC). The extract was analyzed using Py-GC-MS for the respective polymers, while the solid residue was pyrolyzed separately for polyethylene (PE) and polypropylene (PP). The one-step solvent extraction method significantly simplified the sample matrix and improved the sensitivity of analysis. Among the samples, PET was detected in greater quantities in the fine fraction than in the intermediate size fraction, and PET fine particles were located predominantly in the surface sand. Similar to PET, PS was detected at higher mass concentrations in the fine particles in most samples. These results underscore the importance of beach environment for plastic fragmentation, where a combination of factors including UV irradiation, mechanical abrasion, and water exposure promote plastic breakdown. Surface accumulation of fine plastic particles may also be attributed to transport of microplastics through wind and tides. The proposed sample treatment and analysis methods may allow sensitive and quantitative measurements of size or depth-related distribution patterns of microplastics in complex environmental media.

Liquid-liquid extraction of selenium (IV) ions from hydrochloric acid solution using Aliquat 336 dissolved in kerosene.

Solvent extraction of selenium(IV) ions from highly concentrated hydrochloric acid using 0.4 mol/L Aliquat 336 dissolved in kerosene was investigated. As a modifying agent, 1-octanol (10% v/v) was added to the organic phase to avoid the third phase formation. The effect of different parameters affecting the liquid-liquid extraction of selenium(IV) such as the acid concentration, shaking time, metal ion concentration in the aqueous phase, loading capacity, diluents, and temperature, was studied. The results indicate that selenium(IV) is extracted efficiently by 0.4 mol/L Aliquat 336 dissolved in kerosene. It was noticed that the extraction increased with the increase in the acid and Aliquat 336 concentrations, reaching an extraction percentage of about 92% at 8 mol/L HCl and 97.1% at 1 mol/L extractant. The extracted organic species is postulated to be [H2SeO2Cl2.2R4NCl]org by using the slope analysis method, and the value of Kex for selenium(IV) extraction was found to be 26.17 ± 2 M- 2. The structure of the extracted organic species was confirmed by FT-IR. The effect of diluents using various aliphatic and aromatic diluents indicated that kerosene is the most preferred diluent. This is owing to safety ground purpose, economic consideration, the lower cost, availability, and lower toxicity. Thermodynamic parameters indicate the endothermic nature for the solvent extraction of selenium(IV) for the investigated system according to the positive value obtained of the enthalpy change (ΔH). Depending on the obtained results, the method was used to recover selenium(IV) from a simulated solution synthesized in hydrochloric acid medium, which is expected in anode slime leach liquor solution.

Characterization of Camphene- and Fenchol-Based Hydrophobic Eutectic Solvents and Their Application in Aldehyde Extraction.

Binary terpenoid-based eutectic systems consisting of the natural substances camphene (CA), fenchol (FE), thymol (TH), menthol (ME), dodecanoic acid (DA), and 1-dodecanol (DO) are synthesized and screened for their Solid-Liquid Equilibrium (SLE) and eutectic compositions. Out of nine eutectic systems, 13 solvent compositions at eutectic points and next to them, in addition to the reference solvent, TH:ME, are synthesized and applied for the solvent extraction of the aromatic aldehydes vanillin (VAN), syringaldehyde (SYR), and p-hydroxybenzaldehyde (HYD) from an acidic aqueous model solution. The extraction efficiency is determined from aldehyde concentrations measured by High-Performance Liquid Chromatography (HPLC), taking into consideration mutual solubility measured by Karl Fischer titration (KF) and a Total Organic Carbon-analysis (TOC). Physicochemical properties, such as the density, viscosity, and stability of the solvents, are evaluated and discussed. Additionally, 1H-NMR measurements are performed to verify hydrogen bonding present in some of the solvents. The results show that all synthesized eutectic systems have a strong hydrophobic character with a maximum water saturation of ≤2.21 vol.% and solvent losses of ≤0.12 vol.% per extraction step. The hydrophobic eutectic solvents based on CA exhibit lower viscosities, lower mutual solubility, and lower extraction efficiency for the aromatic aldehydes when compared with FE-based solvents. The highest extraction efficiencies for VAN (>95%) and for SYR (>93%) at an extraction efficiency of 92.61% for HYD are achieved by the reference solvent TH:ME (50:50 mol.%). With an extraction efficiency of 93.08%, HYD is most preferably extracted by the FE-DO-solvent (80:20 mol.%), where the extraction efficiencies for VAN and SYR reach their maximum at 93.37% and 90.75%, respectively. The drawbacks of the high viscosities of 34.741 mPas of the TH:ME solvent and 31.801 mPas of the FE-DO solvent can be overcome by the CA-TH solvent, which has a viscosity of 3.436 mPas, while exhibiting extraction efficiencies of 71.92% for HYD, >95% for VAN, and >93% for SYR, respectively.

Optimization and Validation of a Cheaper, Safer, and More Sustainable Methodology for Aflatoxins Determination in Rich-Lipidic Matrices (Pistachio Nuts) Using Deep Eutectic Solvent Extraction and UHPLC-FLD Analysis.

Aflatoxins pose a major health concern and require strict monitoring in food products. Existing methods rely on hazardous organic solvents for extraction, prompting the development of a greener alternative. This study explores deep eutectic solvents (DESs) for aflatoxin extraction from pistachios, a valuable food product prone to aflatoxin contamination. The proposed method utilizes DES extraction followed by solid-phase extraction cleanup and ultrahigh-performance liquid chromatography coupled with fluorescence detector analysis. Recovery rates ranged from 85.5 to 99.1% for pistachios spiked with 1-8 ng/g aflatoxins, in compliance with EU regulations, with coefficients of variation less than 2.94%. The method demonstrates good sensitivity with limits of detection and quantification in the range of 0.02-0.22 ng/g and 0.05-0.72 ng/g, respectively. Greenness assessment using AGREEPrep and White Analytical Chemistry metrics confirms its environmental sustainability. This approach offers a promising, safer, and more eco-friendly alternative for aflatoxin extraction from complex food matrices like pistachios.

Coupling Electrochemical Leaching with Solvent Extraction for Recycling Spent Lithium-Ion Batteries.

We propose coupling electrochemical leaching with solvent extraction to separate and recover Li and Co from spent lithium-ion batteries (LIBs). Electrochemical leaching occurs in the aqueous electrolyte for converting solid LiCoO2 into soluble Li+ and Co2+, in which electrons act as reductants to reduce Co(III) to Co(II). Simultaneously, solvent extraction occurs at the interface of aqueous and organic phases to separate Co2+ and Li+. By capturing and utilizing the protons from P507, leaching yields for both Co and Li exceed ∼7 times than acid leaching without solvent extraction. The extraction efficiency of Co2+ reaches 86% at 60 °C, 3.5 V, while simultaneously retaining the majority of Li+ in the H2SO4 solution. The total leaching amount was improved because the organic phase provides protons to help the leaching of Co2+, and the continuous extraction process of Co(II) maintains the low Co2+ concentration in the aqueous solution. The synergistic interaction between electrochemical leaching and solvent extraction processes significantly reduces the consumption of chemicals, enhances the utilization efficiency of protons, and simplifies the recovery process. The leaching kinetics of Li and Co both conforms well to the residue layer diffusion control model and the activation energy (Ea) values of the leaching for Li and Co are 4.03 and 7.80 kJ/mol, respectively. Lastly, the economic and environmental assessment of this process also demonstrates the advantages of this method in reducing inputs, lowering environmental pollution, and enhancing economic benefits.

Optimization and characterization of aqueous enzyme-assisted solvent extraction of apricot kernel oil.

Abstract: Aqueous enzyme-assisted solvent extraction (AE-SE) of oil from apricot (Prunus armeniaca L.) kernel was investigated in this study and the operational parameters were optimized. After preliminary screening, a cocktail of enzymes (Celluclast 1.5 L and Alcalase Pure 2.4 L [60:40, v/v)] of 1% (v/w) was chosen. The extraction process parameters: temperature (40-60 °C), time (1-5 h), and pH (4-9) were optimized using Box-Behnken design to achieve the highest oil yield (%) and antioxidant activity (DPPH, %). Under optimized conditions, i.e., temperature 40 °C, time 2.5 h, and pH 8.28, the highest oil yield and DPPH were 47.93% and 67.31%, respectively. The gas chromatography analysis disclosed that apricot kernel oil extracted by solvent extraction and AE-SE have similar fatty acid compositions, and the oil is rich in unsaturated fatty acids. The physicochemical analysis showed AE-SE method produces high-quality oil and can be substituted as green technology for industrial oil extraction purposes.

A New Triketone Ligand for Extraction of Lithium from Brines.

Recovery of lithium from brines by liquid-liquid solvent extraction (LLE) with diketones and synergistic co-ligands has been investigated for decades, but industrial application has been limited. In pursuit of a ligand with improved properties, a series of ketonamides with beta-carbonyl groups were designed, synthesized, and tested in extraction of lithium from sulfate and carbonate simulants of clay mineral tailing leachates. The best performing ligand, a novel tricarbonyl amide, was characterized for lithium extraction with and without four synergistic co-ligands. The tricarbonyl amide combined with the synergistic co-ligand Cyanex-923 was absorbed on a resin support. The ligand-modified resin was tested for performance in extraction of dilute brine simulants and up to 60 % recovery of lithium was achieved.

Separation of Pd from Pt and Rh by solvent extraction method from waste solution.

The paper investigated the possibility of extractive separation of palladium from platinum and rhodium with ionic liquid Cyphos IL 101. A technological solution obtained by dissolving waste materials was used as the test material. Based on the experiments performed, it was found that a 10% (v/v) solution of the Cyphos IL 101 ionic liquid in toluene allows the extraction of both Pd and Pt with an efficiency of 99% from the initial solution when extraction is carried out at the pH 0.5, vorg:vaq phase ratio 1:1 and contact time of 15 min. Moreover, the research proved that it is possible to separate Pd from Pt at the stripping stage using a 0.1 mol/dm3 thiourea solution while maintaining a high selectivity coefficient.

Optimization of rare earth magnet recovery processes using oxalic acid in precipitation stripping: Insights from experimental investigation and statistical analysis.

Recycling the valuable metals found in spent permanent magnets (REPMs) poses a significant global challenge for the future. This study examines the efficiency of back extraction of rare earth elements (REEs) by oxalic acid solution from di-(2-ethylhexyl) phosphoric acid (D2EHPA) in recycling REPMs. To evaluate the efficiency of this process, several experiments were carried out using designed BOX-Behnken methodology to investigate the effects of various operational and chemical parameters, including stripping solution to loaded organic phase volume ratio (in the range of 1.0-2.0), oxalic acid concentration (ranging from 0.25 to 0.75 M), the stirring rate (ranged between 150 and 350 rpm), and stripping time (ranging from 15 to 45 min) on the REEs recovery and the purity of final production. Analysis of variance was applied to rigorously examine the results statistically. The results showed that more than 85 % of light and 80 % of heavy REEs can be recovered under optimal conditions. Moreover, the final product contained 43.5 % REEs and approximately 0.1 % iron. The stripping experiment using phosphoric acid as the reagent demonstrated ∼57 % light and ∼4 % heavy REEs recovery. Additionally, the recyclability of the organic phase showed its effective reuse for up to four cycles. This study underscores significant progress in the selective recovery of rare earth elements through a relatively straightforward process consuming mild reagents.

Optimization of accelerated solvent extraction of zeaxanthin from orange paprika using response surface methodology and an artificial neural network coupled with a genetic algorithm.

This study aimed to optimize the accelerated solvent extraction (ASE) condition of zeaxanthin from orange paprika using a response surface methodology (RSM) or an artificial neural network (ANN) with a genetic algorithm (GA). Input variables were ethanol concentration, extraction time, and extraction temperature, while output variable was zeaxanthin. The mean squared error and regression correlation coefficient of the developed ANN model were 0.3038 and 0.9983, respectively. Predicted optimal extraction conditions from ANN-GA for maximum zeaxanthin were 100% ethanol, 3.4 min, and 99.2 °C. The relative errors under the optimal extraction conditions were RSM for 10.46% and ANN-GA for 2.18%. We showed that the recovery of hydrophobic zeaxanthin could be performed using ethanol, an eco-friendly solvent, via ASE, and the extraction efficiency could be improved by ANN-GA modeling than RSM. Therefore, combining ASE and ANN-GA might be desirable for the efficient and eco-friendly extraction of hydrophobic functional materials from food resources. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-023-01514-8.

Degradative solvent-catalyzed extraction of sewage sludge.

It is necessary for the further development of sludge degradative solvent extraction (DSE) to significantly increase the bio-oil yield and adjust its composition. In this study, the effects of MCM-41, HZSM-5, and SSZ-13 on the physical properties, yield, and composition of bio-oil were compared. Results show that all three catalysts effectively promote the conversion of volatiles in the residue to the heavy component (heavy-s). The addition of MCM-41 improved the yieldof both the light component (light-s) and heavy-s. Their yields increased from 8.11% and 20.47% to 14.39% and 29.18%, respectively. Its all-silicon structure and weak acidity have no significant effect on the composition of the bio-oil. HZSM-5 addition increases the light-s yield to 25.58%. Its MFI structure and proper acidity are beneficial to the formation of aromatic hydrocarbons and olefins, while effectively reducing oxygenates. SSZ-13 increases the heavy-s yield to 27.89%, and promoted the formation of nitrogen-containing compounds significantly.

Plutonium Speciation and Oxidation State Distributions in the Presence of Citrate.

We explored the speciation and kinetics of the Pu(VI)-citrate and Pu(III)-citrate systems (pHm = 2.5-11.0, I = 0.1 M NaCl, T = 23 °C, O2(g) < 2 ppm) using ultraviolet-visible-near-infrared (UV-vis-NIR) spectrophotometry, solvent extraction, and PHREEQC modeling. Formation constants were determined for PuO2(HcitH)(aq) (log K°1,1 = 1.09 ± 0.05) and PuO2(HcitH)(citH)3- (log K°1,2 = -0.20 ± 0.07), and evidence for (PuO2)m(citH-k)n(OH)x2m(3+k)n-x was identified under alkaline conditions. Pu(VI) species were found to be less stable in the presence of citrate than in the absence of citrate (t ≤ 168 days); the rate of reduction increased with increasing pH. The direct reduction of Pu(VI) to Pu(IV) was required to fit experimental data in the presence of citrate but did not improve the fit for Pu in the absence of citrate. We also observed increased Pu(III) stability in the presence of citrate (t ≤ 293 days), with higher concentrations of Pu(III) favored at lower pH. Finally, we provide evidence of a radiolysis-driven mechanism for the citrate-mediated reduction of plutonium that involves electron transfer from the oxidative breakdown of citrate. Our work highlights the need to investigate the redox effect of organic ligands on plutonium oxidation states under repository-relevant conditions.