Type Of Solvent Research Articles

Blackcurrant Pomace as a Rich Source of Anthocyanins: Ultrasound-Assisted Extraction under Different Parameters

The industry is currently trying to manage the waste generated during juice pressing. Berry pomace is an especially rich source of many bioactive compounds. Blackcurrant pomace is particularly valuable because of the large amount of extractable anthocyanins remaining in the fruit skin. The aim of the study was to evaluate the effect of ultrasound-assisted extraction (UAE) parameters on the content of anthocyanins and color parameters of blackcurrant pomace extracts. The pomace used for the study was very rich in anthocyanins—an average content of 853.2 mg/100 g fresh weight. The effect of temperature (25, 35, 45 °C), time (15, 30, 60 min) and material/solvent ratio (1:20 or 1:7) on extraction yield was analyzed. The extracts were obtained using two solvents: water–ethanol acidified with HCl and water acidified with citric acid. Either solvent type, as well as the other parameters of the extraction process, have an impact on the level of anthocyanins in the extracts. The lowest range of extraction yield (63–68%) was obtained for a 1:7 ratio with water–citric acid solvent. The highest range of extraction yield (74–93%) was obtained for a 1:7 ratio with water–ethanol solvent. The most efficient method was extraction in a water–ethanol solvent (50/50 v/v) acidified with HCl, at a 1:7 material/solvent ratio, at 35 °C, for 15 min, providing 93% process efficiency. A strong relationship (r > 0.991) was also found between anthocyanin content and color saturation (C*) or hue (h°) in the obtained extracts. Based on the E1% coloring strength results, all the extracts obtained can be considered strong colorants, especially those obtained with the water–citric acid solvent. Ultrasonic extraction can be successfully applied to extract pigments from blackcurrant pomace and obtain, for example, food coloring.

Optimization of microencapsulation of polyaspartic acid ester into UV curable epoxy‐acrylate resin using Taguchi method of experimental design

AbstractDue to fast reaction with isocyanates, polyaspartic acid esters (PAAE) can be used for the development of microcapsules for self‐healing coatings. Microcapsules with encapsulated PAAE into shell formed by UV‐cured commercial epoxy‐acrylate resin were produced through oil‐in‐water emulsion polymerization triggered by UV light. The obtained microcapsules were characterized by FTIR, TGA, optical microscopy, and SEM. Various encapsulation parameters, including core to shell ratio, agitation speed, emulsifier type and concentration, solvent type and its concentration in the oil phase, have been selected at four different levels. Microencapsulation was optimized using Taguchi L16 parameter design approach for determination of desired outcome as larger is better (maximal core content) and nominal is better (microcapsule diameter of 50 μm). It was determined that conditions to prepare microcapsules with the highest core content and the microcapsule size close to 50 μm are rather similar requiring core‐to‐shell ratio at about 4:1, low agitation speed of 500–1000 rpm, and the use of two polymeric emulsifiers poly(vinyl alcohol) and Gum Arabic at concentration of about 2%. Primary benefits of UV‐induced shell formation during microencapsulation of active compounds are remarkably shorter time of the process and possibilities to reach high core content and prepare microcapsules of desirable size.

Plant mediated synthesis of flower-like Cu2O microbeads from Artimisia campestris L. extract for the catalyzed synthesis of 1,4-disubstituted 1,2,3-triazole derivatives.

This study presents a novel method for synthesizing 1,4-disubstituted 1,2,3-triazole derivatives through a one-pot, multi-component addition reaction using flower-like Cu2O microbeads as a catalyst. The flower-like Cu2O microbeads were synthesized using an aqueous extract of Artimisia Campestris L. This extract demonstrated the capability to reduce and stabilize Cu2O particles during their initial formation, resulting in the formation of a porous flower-like morphology. These Cu2O microbeads exhibit distinctive features, including a cubic close-packed (ccp) crystal structure with an average crystallite size of 22.8nm, bandgap energy of 2.7eV and a particle size of 6µm. Their catalytic activity in synthesizing 1,4-disubstituted 1,2,3-triazole derivatives was investigated through systematic exploration of key parameters such as catalyst quantity (1, 5, 10, 15, 20, and 30mg/mL), solvent type (dimethylformamide/H2O, ethanol/H2O, dichloromethane/H2O, chloroform, acetone, and dimethyl sulfoxide), and catalyst reusability (four cycles). The Cu2O microbeads significantly increased the product yield from 20% to 85.3%. The green synthesis and outstanding catalytic attributes make these flower-like Cu2O microbeads promising, efficient, and recyclable catalysts for sustainable and effective chemical transformations.

The mineral phase evolution characteristics and hydration activity enhancement mechanism of steel slag under NaOH alkaline excitation

During the slow cooling process of steel slag, crystals of the inert ore phase (C2F) and active ore phase (C2S, C3S) grow dependently, and the irregular interlacement and coating between ore phases strongly affect the hydration activity of the active ore phase in steel slag. Therefore, in this article, a typical alkaline activator, NaOH, was selected, the solvent type and concentration were optimized, and the etching behavior and mechanism of action of the NaOH alkaline activator on the surface of steel slag particles were clarified by analyzing the mineral phase composition, microstructure, particle size distribution, and pore structure evolution characteristics under alkaline excitation. In addition, the water hydration products, microstructure, exothermic hydration and thermogravimetric data before and after the excitation of steel slag were characterized, revealing the mechanism of enhancing the hydration activity of steel slag under alkaline NaOH stimulation. The results showed that both NaOH aqueous solution and ethanol solution could effectively increase the mass fraction of active mineral phases in steel slag; among them, the 0.08 mol/L NaOH ethanol solution had the best chemical activation effect on the steel slag. Compared with that of the raw steel slag, the total mass fraction of the active mineral phases (C2S and C3S) increased from 37.3 wt% to 45.6 wt%, and the mass fraction of the inert mineral phase C2F decreased from 38.3 wt% to 19.1 wt%. The consumption of active mineral phases in steel slag is reduced by the water in the activator. The alkaline activator erodes the dense inert mineral phase C2F on the surface of the steel slag particles, resulting in etching pits that expose the active silicate mineral phase and provide additional hydration sites. The cumulative heat release from the steel slag after alkaline excitation was 116.27 J/g at 72 h, which was 66.88 J/g higher than that of the raw steel slag. These conditions significantly improved the early hydration performance of the steel slag and promoted the formation of amorphous cementitious products (CH, C-S-H and AFt) in the steel slag system, which subsequently filled the capillary pores of the steel slag and formed a denser microstructure.

Implementation of simple and effective fine droplet formation-based spray-assisted liquid phase microextraction for the simultaneous determination of twenty-nine endocrine disruptor compounds and pesticides in rock, soil, water, moss, and feces samples from antarctica using gas chromatography-mass spectrometry

This study established the simultaneous determination of the selected endocrine-disrupting compounds (EDCs) and pesticides in rock, soil, water, moss, and feces samples collected from the Antarctic region. The spray-assisted droplet formation-based liquid phase microextraction (SADF-LPME) coupled to GC–MS system was developed and validated for the screening and monitoring of 29 selected EDCs and pesticides. Binary solvent system, 1:1 (v/v) dichlormethane: 1,2-dichloroethane mixture was employed as an extraction solvent and sprayed onto sample or standard solutions using a straightforward and practical spray apparatus. The factors affecting the extraction process such as extraction solvent type and ratio, extraction solvent volume (spray repetition), vortexing period, and sample pH were properly optimized. Analytical figures of the merit of the method were recorded under the optimal extraction/chromatographic conditions. The LOD, LOQ, and enhancement factor were in the range of 1.0 to 6.6 ng/g, 3.2 to 22.1 ng/g, and 3.7 to 158.9, respectively. The method demonstrated a good linear working range for all the selected analytes with proper coefficients of determination. The usability and reliability of the microextraction strategy was confirmed using seawater, moss, and soil samples, and the %recoveries were within an acceptable range (> 70%) for all examined samples. The environmental samples collected from the Horseshoe and Faure Islands of the Antarctica region were analyzed to assess the potential pollution of EDCs and pesticides. This method has the potential to be employed for the analysis of EDCs in routine analytical laboratories and for controlling and screening the organic pollutant content of different environmental samples.

Capillary electrophoresis separations with deep eutectic solvents as greener separation media: A proof-of-concept study

Capillary electrophoresis (CE) has conventionally been classified into aqueous and non-aqueous categories based on the types of buffer solvents employed. Traditionally, non-aqueous CE has always been associated with the use of organic solvents, which are considered hazardous to health and environmentally detrimental. In this work, we introduce deep eutectic solvents (DESs) as CE separation media for the first time, presenting a novel and environmentally friendly approach to CE separations. The DES employed consists of proline and urea (Proline:Urea, PU), both of which are naturally occurring compounds that are readily available, cost-effective, and environmentally benign. Various fundamental aspects of the DES-type CE media were investigated, including thermal property, viscosity, electroconductivity, Joule heating effect, and compatibility with detectors. A simulated complex mixture of ten naphthalene-based compounds with varied charges and sizes was separated using the DES-based medium in capillary zone electrophoresis (CZE) mode. Moreover, we also established a DES-based micellar electrokinetic chromatography (MEKC) system utilizing Tween-20 as the surfactant. Six structurally similar naphthalene derivatives (isomers) that couldn't be resolved by CZE were effectively separated due to their strong hydrophobic interaction with Tween-20 micelles within the DES medium. Given that DESs are “designer” solvents with highly tunable properties and environmentally friendly characteristics, this study demonstrates the potential of employing DESs as an alternative to organic solvents for greener CE separations.

A novel removal of Ni2+ ions from water solutions using dispersive solid-phase extraction method with nano Fe3O4/chitosan-acrylamide hydrogel.

The effluent release containing heavy metals as Ni2+ ions has drastic risks to both the natural environment and human health. In this research, the nano Fe3O4/chitosan-acrylamide hydrogel was prepared as a novel nano sorbent for dispersive solid-phase extraction of Ni2+ ions and applied to the water sample solution. The pH, amount and type of elution solvent, the extraction time, etc. were optimized to improve the efficiency of the proposed method. Analytical parameters such as concentration factor and relative standard deviation (%) were achieved as 33.3 and 1.8%, respectively. The capacity in equilibrium sorption was calculated at 22.54 mg g-1. Furthermore, to estimate the adsorption mode, Freundlich, Langmuir, and Temkin models were fitted with experimental isotherm data. Besides, to check the basic process of the metal adsorption mechanism, pseudo-first-order, pseudo-second-order, and Roginsky-Zeldovich models were investigated and the results were fitted with the pseudo-second-order model. The value of change in entropy (⊿S) obtained is -65.24 (J(mol K)-1). Negative values of change in enthalpy, ⊿H in (kJ mol-1) is -24.45 (kJ mol-1) which indicates both physical and chemical adsorptions involved in the process of adsorption. Finally, the nano Fe3O4/chitosan-acrylamide hydrogel exhibited high performance to remove the Ni2+ ions from water sample solution.

High Response and Selectivity of the SnO2 Nanobox Gas Sensor for Ethyl Methyl Carbonate Leakage Detection in a Lithium-Ion battery.

It is well-known that metal-oxide semiconductors (MOS) have significant gas sensing activity and are widely used in harmful gas monitoring in various environments. With the rapid development of new energy vehicles, the monitoring of the gas composition and concentration in LIB has become an effective way to avoid safety problems. However, the study of typical electrolyte solvent detection, such as EMC and DMC detection by the MOS sensor, is still in its infancy. Here, the SnO2 nanoboxes are synthesized by coordination dissolution using cubic Cu2O as the template, and its sensor shows high sensitivity (0.27 to 10 ppb EMC), excellent response (32.46 to 20 ppm EMC), and superior selectivity. Additionally, the sensor possesses fast and clear response to lithium-ion battery (LIB) leakage simulation tests, suggesting that it should be a promising candidate for LIB safety monitors. These sensing performances are attributed to large specific surface area, small grain size, and high size/thickness ratio of nanoboxes. More importantly, DFT calculations confirm the adsorption of EMC on the surface of the SnO2 nanoboxes, and the EMC decomposition processes catalyzed by SnO2 are deduced by in situ FTIR and GC-MS.

Assessment of alcoholic extraction of Jatropha curcas L. oil for potential reactive extraction towards fatty esters

This work dealt with the extraction of Jatropha oil using methanol and ethanol as solvents to evaluate a potential integration of extraction-transesterification to produce fatty esters. For comparison purposes, additional extractions were carried out with n-hexane as industrial benchmark solvent. The effects of type of solvent, particle size (0.44–3.57 mm), and seed-to-solvent ratio (1:4, 1:6, and 1:8 w/v) were evaluated with respect to oil yield, efficiency, saponification index (SI, mgKOH/g) and acid value (AV, mgKOH/g). As expected, highest oil yield (50.4% wt.) was obtained using n-hexane, but with a low selectivity to saponifiable materials (SI ∼ 166). When using alcohols, oil yield (8–31% wt.) and efficiency (17–70%) were lower and the quality of the oil was poor (SI 32–176; AV 4–5). Results indicated that, differently from previously claimed, integrated alcoholic extraction with alkaline transesterification would not be suitable for fatty esters production. By using experimental data and the Hildebrandt solubility parameters, it was possible to fit a continuous model suitable for further optimization and solvent selection in Jatropha oil extraction. The model was validated by predicting expected SI and oil yield using an untested solvent (i.e. petroleum ether), and difference between model predictions and experimental observations were less than 3%.

Dispersive solid phase extraction of perfluorooctanoic acid from wastewater using chromium-doped CoFe layered double hydroxide for determination by LC-MS/MS

Polyfluoroalkyl substances (PFAS) are persistently dangerous substances in the environment, threatening human health even in very low concentrations. This work introduced a dispersive solid phase extraction (DSPE) based on Cr-doped CoFe layered double hydroxide (LDH), which was used as the extraction phase for the effective removal of perfluorooctanoic acid (PFOA) from wastewater samples. Cr-doped CoFe LDH was synthesized using the facile co-precipitation method. Successful partial substitution of Fe3+ by Cr3+ cations in the crystalline lattice of CoFe LDH was affirmed by energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and elemental dot-mapping analysis. Layered morphology was observed for both bare and Cr-doped CoFe LDH in scanning and transmission electron microscopy images. The influence of diverse parameters, including sorbent mass, eluent solvent type, volume of eluent, agitation mode, adsorption time, and pH, was assessed on the extraction of PFOA by Cr-doped CoFe LDH. The experimental data from the effective DSPE followed by liquid chromatography–tandem mass spectrometry exhibited a low limit of detection of 0.03 µg/L, broad linear range (0.1–300 µg/L and R2 ≥ 0.997), and good repeatability (6.7 %, n = 5 intraday) for the enrichment and determination of PFOA in wastewater samples.

Simultaneous Determination of Pesticides in Lonicera japonica by QuEChERS Preparation and Gas Chromatography-Mass Spectrometry (GC-MS)

Lonicera japonica is a commonly used Chinese herbal medicine, but few studies have focused on its pesticide residues. In this study, a quick, easy, cheap, effective, rugged, safe (QuEChERS) pretreatment combined with gas chromatography-mass spectrometry (GC-MS) was established to determine 16 pesticides in L. japonica. Various factors including the type and volume of extraction solvent, times of ultrasound-assisted extraction, and type and weight of purifying agents were optimized. The established method showed good linearity with correlation coefficient (r) > 0.99 within the range of 0.01–5.0 mg·L−1, and average recoveries (AR) were 82.3%-102.5% at spiking levels of 0.01, 0.1, and 0.5 mg·kg−1 with relative standard deviations (RSD) of 0.43%-4.75%. Only bifenthrin and fenvalerate can be detected with maximum detected concentrations of 1.41 and 0.13 mg·kg−1. The results showed that the established method can be applied to detect pesticide residues in L. japonica with potential applications for other Chinese herbal medicines.

Efficient osmotic energy recovery from organic wastewater using a two-dimensional porphyrin-based metal-organic frameworks membrane

Harvesting osmotic energy plays a crucial role in addressing the global depletion crisis of fossil energy and achieving a structural transformation in energy. However, current research predominantly focuses on osmotic energy stored in natural seawater, with relatively little attention given to other saline sources such as industrial wastewater. In this study, a two-dimensional Cu-TCPP metal-organic framework (MOFs) nanosheet was prepared, and a nanofluidic membrane with high osmotic energy recovery efficiency from industrial organic saline wastewater was constructed. In a LiCl methanol solution system with a 100-fold salinity gradient, the Cu-TCPP membrane achieved a stable power density of 4.87 W/m2. Simulation analysis suggests that the membrane's efficient ion-selective transport in the organic system can be primarily attributed to abundant diffusion pathways, including intrinsic pores in the nanosheet and two-dimensional nanochannels between adjacent nanosheets. Furthermore, the physicochemical properties of the nanochannel membrane and the type of solvent and ions significantly impact osmotic energy recovery efficiency in organic solvents. This work provides a novel approach to the treatment and resource utilization of industrial organic wastewater in the chemical and pharmaceutical industries.

Activated Carbons and Chitosan Adsorbents in Removing Contaminants from Water

Being more and more widely used for a variety of water treatments, chitosan and activated carbons are playing an increasingly significant part nowadays. Activated carbons purify water through the pore structure and adsorb ions or other particles. Chitosan also adsorb a large amount of metallic ions and purifies water through the reactions by the functional groups. This paper discusses the different features of the two substances and then gives a comparison between the two types of adsorbents by comparing their characteristics, conditions and applications. Specifically, the suitable temperatures, the specific modifications and solubility are discussed, together with other factors. The difference in their physical and chemical properties plays an important role in the comparison. For physical properties, the activated carbons have strong mechanical strength and are soluble in many types of solvents. By contrast, chitosan is generally soluble in an acidic solution. There are also some differences in the adsorption abilities and ways to purify solutions. Next, chitosan is more easily dissolved in solution with low PH and at room temperature. However, the activated carbons require lower PH and lower temperature to be dissolved. Then, activated carbons are more likely to cause secondary pollution due to the impurities in the activated carbons. The two substances require different modifications to increase the rate of adsorption. As a result, the firms should consider the features of the two types of adsorbents and choose the better one. They should also understand the suitable conditions for each adsorbent.

Substituent and Solvent Effects on the Spectral Properties of 3-Substituted Derivatives of 4-Hydroxycoumarin

Solvent and substitution effects on the UV/Vis spectroscopic and fluorescence behaviour of seven synthesized 3-substituted 4-hydroxycoumarin derivatives were tested. The tested compounds were dissolved in ethyl acetate, acetonitrile, and dimethyl sulfoxide. Absorption and emission spectra were recorded in the range of 200–800 nm. All tested 4-hydroxycoumarin derivatives showed good absorption in a wide range of 200–550 nm, depending on the properties of the substituents on the benzene ring of the cinnamoyl moiety and the type of solvent. In comparison to the unsubstituted analogue, compounds with an electron-donating group exhibited bathochromically shifted UV/Vis absorption and emission spectra. The highest fluorescence quantum yield was observed for compounds with dimethylamino and acetamido groups as substituents at the benzene ring. Considering that both substitution and solvent affect the absorption and emission spectra of the tested compounds, it can be concluded that judiciously selecting these parameters can improve their absorption and fluorescence properties, making them suitable for various analytical uses.

Tuning CuO crystallite size by different solvents for higher alcohols synthesis from syngas over CuZnAl catalyst

The crystallite size effect of metal oxides plays a vital role in the field of heterogeneous catalysis research. Herein, CuZnAl catalysts with varying CuO crystallite sizes are synthesized by coprecipitation method employing various solvents. The catalytic performance of CO hydrogenation is studied and the physical and chemical properties of catalysts are characterized by XRD, H2-TPR, N2 adsorption-desorption, and NH3/CO2-TPD-MS. The results indicate that the different types of solvents can effectively regulate CuO crystallite size, thereby affecting its reducibility and catalytic activity. Most importantly, we observe that CuO crystallite size is positive correlated with reduction temperature and negative correlated with C2+OH selectivity. The catalyst employing ethanol as a solvent exhibits the highest CO conversion (22.91 %) and the optimum proportion of C2+OH in total alcohols (18.96 %), which indicates that smaller CuO crystallite size facilitates reduction of Cu species and generation of larger pore size as well as suitable acid-basic sites, thereby promoting higher alcohols formation. Therefore, these findings greatly broaden understanding the size effect of CuO, providing a new strategy for rational design Cu-based catalysts for higher alcohols synthesis.

Peripheral Neuropathy Resembling CIDP Following Exposure to Toxic Fumes in Shoe Factory: A Case Report

Abstract Different types of solvents and adhesives are used in a shoe factory. The toxic chemicals can cause acute and chronic effects on the central and peripheral nervous system. Here, we report a case of a 25-year-old young man working as a coloring and gluing worker in a shoe factory, who presented with progressive quadriparesis following exposure of six months. Some of his coworkers also developed a similar illness. Nerve conduction velocity studies of the patient showed combined sensory and motor demyelinating and axonal polyneuropathy. Cerebrospinal fluid (CSF) analysis was normal. With conservative management and physiotherapy, there is a gradual improvement of the condition in the patient who can ambulate independently now.

The Variation Effect of Solvents on the Physicochemical Properties Baobab (Ophelussitularius) Seeds Oil

It is remarkable to notice that Baobab seeds are normally discarded in Sudan, without knowing the great wealth hidden. The present study was conducted to determine physicochemical properties of Baobab (Ophelussitularis) seeds oil and select proper solvent for oil extraction from seeds which contain approximately 22-45%, used n-hexane and ethanol as solvents, leaching was done by solid extraction method. Physicochemical properties of the Baobab seeds oil were evaluated by standard and established methods. Oils and solvents were separated using rotary evaporator, recovery solvent were 91.2% and 75% for n-hexane and ethanol respectively. The obtained Baobab oils color were golden yellow (reddish yellow) not effected by type of solvent, it showed resistance to change in color, results showed the maximum Baobab oil yields were 16% and 13.5 % for n-hexane and ethanol respectively. Crude protein CP was found to be13.475 g/100 g, oil content was 13.26 g/, Saponification value SV 338.4925 g and 406.725 g/100 g for Baobab oil extracted with n-hexane and ethanol respectively. Results were obtained for ash content, crude fiber, acid value, FFA and rheological properties. Physicochemical properties indicated that n-hexane was more suitable to extract Baobab oil more than ethanol and recover easy. The difference was clearly visible in PV, AV and µ, while n-hexane yields pure oil more than ethanol. All those results detected that seeds of Baobab are beneficial if they extracted using n-hexane. It is recommended to conduct additional research on this issue and insert other solvents to select the best solvent and study the effect of different solvents on the properties of resulting oil.

Dynamic macromolecular material design: the versatility of cucurbituril over cyclodextrin in host-guest chemistry.

The keto-enol tautomerism of avobenzone (AVO) is pivotal to its photostability, influenced by microenvironmental factors, such as, the type of solvent and complexation with macrocyclic compounds. This study explores the effect of host-guest complexation on AVO photostabilization, employing cucurbit[7]uril (CB[7]) and β-cyclodextrin (β-CD) to form inclusion complexes. CB[7] exhibits a higher affinity to the keto form of AVO, a UVC radiation absorber. The complexed keto form facilitates the regeneration of the enol form, reducing skin permeation. Spectroscopic and thermal analyses confirm 1 : 1 AVO-CB[7] and AVO-β-CD complex formation. Computational and MD simulations show that host-guest complex is favored over isolated AVO and β-CD or CB[7] molecules by 95-125 kJ mol-1, depending on the presence of implicit solvent. Both macrocycles enhance AVO photostabilization in aqueous environments, with CB[7] displaying greater selectivity for the keto form, while β-CD shows ethanol concentration-dependent binding.

Elimination of surface defects in luminescent crystals through solid-liquid interface friction.

In this work, we report a simple yet robust strategy for eliminating surface defects in red-emitting fluorides through solid-liquid interface friction under elevated temperature and high pressure. This method is minimally dependent on the solvent type and especially excels at stripping away the abundant surface defects caused by mechanical crushing.

Coefficient of diffusion of tannins in extracts from red and black hawthorn fruit

One of the main parameters of the extraction process is the coefficient of diffusion. It gives information about the diffusion properties of the material to be extracted and depends on various factors: raw material structure, solvent type, temperature, process duration, etc. Determination of molecular diffusion coefficients in extraction from red (Crataegus monogyna Jacq.) and black (Crataegus nigra Waldst & Kit) hawthorn is an objective of the work. The extracts were obtained by ultrasonic extraction with 50 and 70% ethanol at three temperatures (20, 40 and 60°C). The highest values of coefficients for both hawthorn species were obtained at 60°C with 50% ethanol – 5.13.10-6 m2/s for black hawthorn and 6.4.10-6 m2/s for red hawthorn.