Addition Of Organic Solvents Research Articles

Understanding and enhancing the phase stability of fast pyrolysis oils through ternary phase diagrams

Fast pyrolysis oils (FPOs), derived from various biomass feedstocks, hold promise as carbon–neutral fuels. However, their industrial use is hindered due to phase separations during storage, transportation and co-processing, with limited understanding of the root causes that drive this phenomenon. This study aims to elucidate the kinetic stability of FPO by developing ternary phase diagrams and exploring the effects of the temperature and addition of organic solvents on the aging. The phase stability of FPO was found to be determined by the fraction of pyrolytic lignin (PL), mixed solvent (MS), and water. Even at 25 °C, phase separations could consistently occur when the PL content exceeded 56 wt% or the MS content fell below 28 wt%. Heating the FPO to 50 °C–80 °C led to a decrease in the water-soluble content and an increase in the water-insoluble content, while the water content remained relatively unchanged, indicating the transition of the water-soluble content to water-insoluble content was closely related to FPO phase separation during aging at elevated temperatures. Moreover, the solvents could slow the aging of the FPO in the order of 2-propanol > ethanol > methanol > ethylene glycol > glycerol. Thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR-spectroscopy) analysis further revealed changes in both the chemical compositions and polymerizations during aging, in which alcohols were identified as effective inhibiters to slow the aging. These new findings provide promising pathways to controlling the FPO phase stability through solvent selections and will advance the adoptions of FPOs.

A Time-Interval Strategy to Prepare Porous SiO2 Spheres with Adjustable Core-Shell Ratio for Multiple Guest Loading.

Porous microspheres with desired pore size and distribution are in high demand for loading various guest materials, especially various pollutants that are several nanometers in size or stably suspended in liquid. Herein, multilevel porous SiO2 microspheres with arbitrarily adjustable core-shell ratios are prepared by solely regulating the time interval between the start of the hydrolysis reaction and the addition of organic solvent. The core-shell ratio of the SiO2 microspheres increases gradually with prolongation of the addition time interval; meanwhile, the specific surface area can be adjusted from 543.2 m2 g-1 to 992.9 m2 g-1, and the average pore diameter varies from 2.3 to 5.7 nm together with a high pore volume reaching 0.91 cm3 g-1. Moreover, the hierarchical core-shell SiO2 microspheres with an adjustable core-shell ratio, a large specific surface area, and a multilevel pore size could be obtained on a large scale. These SiO2 microspheres demonstrate excellent performance in coloading platinum nanoparticles and various dye molecules, suggesting their great potential in treating various pollutants in printing and dyeing wastewater.

Morphology and photocurrent response of TiO2 nanotubes prepared in electrolytes containing different content of polyethylene glycol

In order to investigate the effect of organic electrolytes on the photocurrent performance of TiO2 nanotubes, four kinds of fluoride containing electrolyte were prepared. This work focuses on the effect of electrolyte on the photocurrent response of TiO2 nanotubes. The results show that the electrolyte is an important influence on the photocurrent response. Appropriate proportion of polyethylene glycol (PEG) organic solvent can improve the performance of photocurrent response. The addition of excessive organic solvent will make TiO2 nanotubes lose the ability of photocurrent response. Suitable surface porosity is a necessary condition for the sample to have photocurrent response. Too low porosity hinders the photoelectric property. The reason for the better photoelectric properties of the sample prepared in 50 wt% PEG electrolyte is explained by the ionic current and electronic current theory. The results show that a more stable ratio of accumulated charge by ionic and electronic currents per unit area creates a more stable photocurrent response when the voltage is increased from 40 V to 60 V.

Effect of organic solvent additives on the enhancement of ultrasonic cavitation effects in water for lithium-ion battery electrode delamination

Ultrasonic delamination is a low energy approach for direct recycling of spent lithium-ion batteries. The efficiency of the ultrasonic delamination relies both on the thermophysical properties (such as viscosity, surface tension, and vapour pressure) of the solvent in which the delamination process is carried out, and the properties of the ultrasound source as well as the geometry of the containment vessel. However, the effect of tailoring solutions to optimise cavitation and delamination of battery cathode coatings has not yet been sufficiently investigated. Acoustic detection, high-speed imaging, and sonochemiluminescence (SCL) are employed to study the cavitation processes in water-glycol systems and identify the effect of tailoring solvent composition on cavitation strength. The addition of small volume fractions of organic solvent (ca. 10–30 vol%), including ethylene glycol or glycerol, to the aqueous delamination solution were found to significantly improve the delamination efficiency of lithium-ion battery cathode coatings due to the alteration of these thermophysical properties. However, greater volume fractions of glycol decrease delamination efficiency due to the signal-dampening effect of viscosity on the ultrasonic waves. The findings of this study offer valuable insights for optimising ultrasonic bath solution composition to enhance film delamination processes.

Optimization of a mass spectrometric analytical method for the quality assessment of insulin and its analogs.

The principal aim of this study was to optimize analytical methodology based on mass spectrometry for the evaluation of the quality of recombinant human insulin and its analogs. In this study ESI-MS was used to assess the quality of human insulin, short acting insulin analogs, insulin lispro, insulin aspart and insulin glulisine and long acting analogs including insulin glargine, insulin degludec, and insulin detemir, in respective pharmaceutical formulations. In this study, with the aimed to optimize analytical conditions, different factors influencing the analytical performance such as pH, ionic strength, sample dilution, organic solvent addition were addressed. The study results demonstrated that MS is a suitable technique for the analysis of biotechnological compounds like insulin and its analogs. Although the obtained results provide an important information regarding this methodology, further studies are needed to validate this analytical approach and check for its suitability to be used in the regulatory environment.

The role of the cation and anion in aqueous liquid chromatography with sodium dodecyl sulphate and imidazolium-based ionic liquids as mobile phase reagents

BackgroundIn reversed-phase liquid chromatography, solute retention is primarily influenced by interactions between a nonpolar stationary phase and a moderately polar hydro-organic mobile phase, based on the solute lipophilicity. However, challenges regarding retention and peak tailing can arise due to ionic interactions between positively charged analytes and free silanols present on silica-based stationary phases. To address these challenges, incorporating surfactants and ionic liquids (ILs) into the mobile phase offers an effective solution. These additives synergistically enhance chromatographic performance through electrostatic and lipophilic interactions, which enable fine-tuning of selectivity and improved separation efficiency. ResultsThis study explores the chromatographic behaviour of several basic compounds in aqueous mixtures containing the anionic surfactant sodium dodecyl sulphate (SDS), above its critical micellar concentration, combined with various 1-alkyl-3-methylimidazolium-based ionic liquids (ILs) featuring chloride, tetrafluoroborate, and hexafluorophosphate anions, all without the addition of organic solvents. Specifically, this research investigates the influence of different anion types within the ILs and considers the impact of the IL cations. Analysis of solute peak profiles reveals narrow and symmetrical peaks. By introducing tetrafluoroborate and hexafluorophosphate IL anions into a mobile phase that contains an anionic surfactant, the study sheds light on the interactions occurring within the chromatographic column. This enhanced understanding of the combined effects of surfactants and ILs contributes to refining chromatographic methodologies. SignificanceThis research highlights the importance of carefully selecting the appropriate IL when incorporating it into a micellar mobile phase alongside SDS. This combination results in practical retention times that surpass the performance achieved with either the surfactant or IL alone in the mobile phase. The study particularly emphasises the impact of the IL anion, especially in the absence of SDS and organic solvents. This unveils interactions that are otherwise obscured in micellar and hydro-organic media, providing new insights into chromatographic dynamics.

Theoretical study on the energy storage performance of Electrical double layer supercapacitors with choline amino acid ionic liquids electrolyte

Choline amino acid ionic liquids have attracted much attention in recent years due to their simple extraction process, rich sources, and easy degradation. Due to the high viscosity of such ionic liquids, the addition of organic solvents can adjust the transport performance of ionic liquids. Here, we explore the effects of different solvents (methanol, ethanol) and different temperatures on the diffusion properties and conductivity of ionic liquids through molecular dynamics simulations. The results showed that with the increase of temperature, the conductivity linearly increased. The addition of organic solvents can improve the conductivity of ionic liquids, and the addition of methanol solvent has a higher compatibility with choline amino acid ionic liquids. The conductivity after mixing methanol and choline glycine in a certain proportion is 5 times higher than before. In addition, this article investigated the performance of choline glycine ionic liquid electrolytes in Electrical Double Layers (EDLs) near planar graphene electrodes. The results indicate that similar double layer structures and double layer capacitors can be observed regardless of whether solvents are added.

A Cellulose Reinforced Polyacrylamide/Polyvinyl Alcohol Dual Network Hydrogel for Flexible Sensors

AbstractIn this paper, polyacrylamide (PAM) was used as the main matrix material to form the first layer network structure, and polyvinyl alcohol (PVA) was used as the secondary matrix material to form the second layer network structure. The hydrogels were prepared by free radical in‐situ polymerization and physical cross‐linking. This hydrogel was characterized not only by its semi‐interpenetrating network structure, in which cellulose nanocrystals (CNC) penetrate through the polyacrylamide network but also by the physically and chemically cross‐linked hybrid PAM/PVA double network. The structure and appearance of the hydrogels were characterized by scanning electron microscope and Fourier transform infrared spectrometer, and a series of tests were carried out to detect their mechanical properties, electrical properties and sensing properties. The results show that the hydrogel has good mechanical properties (the elongation at break can reach 600 % and the stress at break can reach 0.16 MPa), and the hydrogel also has good sensing and electrical properties. The addition of organic solvents makes the hydrogels have excellent antifreeze and water retention properties and also have excellent swelling properties. Therefore, the PAM/PVA/CNC dual network interpenetrating composite hydrogel has potential application value in the field of flexible sensors.

Organic solvent-assisted ethylenediamine pretreatment to improve the high-value utilization efficiency of corn stalk

In order to achieve the goal of carbon neutrality, it is an important way and a great challenge to realize the full-component conversion of lignocellulosic biomass via bio-refinery. In this study, the pretreatment method of organic solvent-assisted ethylenediamine was used to separate cellulose, hemicellulose, and lignin in corn stalk. The effects of different organic solvents on the separation ability were studied, and the separated products were transformed into high-value products. Specifically, the structures of solid residue, regenerated hemicellulose, and regenerated lignin were analyzed and applied to pyrolysis saccharification (at 500℃ for 30 min), information anti-counterfeiting, and selective detection of Fe3+ respectively. The results showed that the lignin removal ratio of 1-butyl-3-lethylimidazolyl chloride/ethylenediamine (IL/EDA) system could reach 96.05 % under the pretreatment condition of 200℃ for 2 h, and the yield of Levoglucosan obtained from pyrolysis bio-oil reached 169.70 mg·g−1 with high selectivity. Moreover, IL/EDA pretreatment increased the nitrogen content of lignin and hemicellulose, enhanced the fluorescence intensity, and effectively realized selective detection and information encryption. Furthermore, Density functional theory (DFT) calculation proved that the addition of organic solvents was beneficial to the reaction between lignin and ethylenediamine (EDA). The Fukui function was used to explore the reaction site between EDA and lignin. In addition, the mass balance of the pretreatment process was also described. This study realized the high-value application of all components of lignocellulose and provided a new process for the efficient utilization of green carbon resources.

Incorporation of canola meal as a sustainable natural filler in PLA foams

The canola oil industry generates significant waste as canola meal (CM) which has limited scope and applications. This study demonstrates the possibility of valorization of CM as a sustainable natural filler in a biodegradable polymer composite of Poly(lactic acid) (PLA). Generally, interfacial bonding between natural fibers and the polymer matrix in the composite is weak and non-uniform. One possible solution is to derivatize natural fibre to introduce interfacial bond strength and compatibility with the PLA polymer matrix. Here, CM was succinylated in a reactive extrusion process using succinic anhydride at 30 wt% to get 14% derivatization with 0.02 g of -COOH density per g of CM. The CM or succinylated CM at 5 and 15 wt% was co-extruded with amorphous PLA to get composite fibers. CM-PLA and succinylated CM-PLA biocomposites were foamed using a mild and green microcellular foaming process, with CO2 as an impregnating agent without any addition of organic solvents. The properties of the foams were analyzed using differential scanning calorimetry (DSC), Dynamic mechanical thermal analysis (DMTA), shrinkage, and imaging. The addition of CM or succinylated CM as a natural filler did not significantly change the glass transition temperature, melting point, percent crystallization, stiffness, and thermal stability of PLA foams. This suggests succinylation (modification) of CM is not a mandatory step for improving interphase compatibility with the amorphous PLA. The new PLA-CM foams can be a good alternative in the packaging industry replacing the existing petroleum-based polymer foams.Graphical

Preparation of a novel hyaluronic acid-based separable hydrogel microneedle with niacinamide to treat pigment deposition using solvent-free solid-state crosslinking method

With the increase in age and prolonged exposure to ultraviolet radiation, especially on the face, pigment deposition often has a negative impact on individuals physically and emotionally. In order to address this issue, a solvent-free solid-state crosslinked hyaluronic acid (HA)-based separable hydrogel microneedle (SHMN) was developed by combining the advantages of hydrogel microneedle and soluble microneedle. This microneedle could separate the needle tip from the backing within five minutes and had the advantage of slow drug release. Hydrogel microneedle tips were prepared by solid-state crosslinking method of HA and poly (methyl vinyl ether)-maleic acid (GAN) for the first time. This crosslinking method without the need for dialysis or the addition of organic solvents, making it a safer, more reliable, and significantly time-saving process compared to previous methods. The soluble material polyvinylpyrrolidone (PVP) was selected as the root and backing of the microneedle. When the microneedle penetrated the skin and contacted with interstitial fluid, the bottom of the microneedle dissolved, and the tip of hydrogel loaded with drugs was separated from the shaft. In addition, the microneedle patch has high drug loading and excellent mechanical properties, which can meet the effective treatment of skin pigmentation.

Facile preparation of Bacterial cellulose‐SiO2 composite aerogel with good mechanical strength and thermal stability

AbstractBacterial cellulose is a natural biopolymer with an ultrafine nanofibrous reticulated matrix and crosslinking active sites. In this work, composite silica aerogels were prepared using a two‐step acid‐base catalysis and ambient pressure drying, with methyltriethoxysilane as the silica precursor and a trace amount of bacterial cellulose as the silicon skeleton reinforcement. The preparation was carried out in water without the addition of other organic solvents and without solvent replacement. The preparation conditions were optimized, and the prepared composite aerogels were characterized using SEM, BET, FTIR, a contact angle meter, and GA‐DTA. The results showed that the introduction of a trace amount of bacterial cellulose could obviously change the morphology and hydrophilicity of the aerogels, and increase its compressive strength up to 5 MPa without significant changes in its specific surface area and density. The addition of bacterial cellulose helped the aerogels maintain its original shape after being heated at high temperatures.

Ultrafast universal fabrication of configurable porous silicone-based elastomers by Joule heating chemistry

Silicone-based elastomers (SEs) have been extensively applied in numerous cutting-edge areas, including flexible electronics, biomedicine, 5G smart devices, mechanics, optics, soft robotics, etc. However, traditional strategies for the synthesis of polymer elastomers, such as bulk polymerization, suspension polymerization, solution polymerization, and emulsion polymerization, are inevitably restricted by long-time usage, organic solvent additives, high energy consumption, and environmental pollution. Here, we propose a Joule heating chemistry method for ultrafast universal fabrication of SEs with configurable porous structures and tunable components (e.g., graphene, Ag, graphene oxide, TiO2, ZnO, Fe3O4, V2O5, MoS2, BN, g-C3N4, BaCO3, CuI, BaTiO3, polyvinylidene fluoride, cellulose, styrene-butadiene rubber, montmorillonite, and EuDySrAlSiOx) within seconds by only employing H2O as the solvent. The intrinsic dynamics of the in situ polymerization and porosity creation of these SEs have been widely investigated. Notably, a flexible capacitive sensor made from as-fabricated silicone-based elastomers exhibits a wide pressure range, fast responses, long-term durability, extreme operating temperatures, and outstanding applicability in various media, and a wireless human-machine interaction system used for rescue activities in extreme conditions is established, which paves the way for more polymer-based material synthesis and wider applications.

Facile dissolution of cellulose by superbase-derived ionic liquid using organic solvents as co-solvents at mild temperatures

Dissolving cellulose at low temperatures is a key step in its efficient utilization as a renewable resource to produce high-value-added platform chemicals and high-performance materials. Here, the potential of four aprotic organic solvents was investigated for use as co-solvents with a sustainable DBU-derived ionic liquid (SIL) for the low-temperature dissolution and regeneration of cellulose. Combined experiments, density functional theory calculations, and molecular dynamic simulations were performed. The type and amount of co-solvent were found to have a significant impact on the solubility of cellulose, the dissolution process, and the structure of regenerated cellulose. The addition of organic solvents can significantly reduce the cellulose dissolution temperature and increase the solubility. Among the solvents assessed, 40 wt% DMSO exhibited the most effective synergistic interaction with SIL, where the solubility of cellulose was 14.6 wt% at 75 °C. Subsequently, the effects of the different types and amounts of co-solvents on the microscopic morphology and chemical structure of regenerated cellulose were thoroughly explored. The results showed that different types of organic solvents had different effects on the microstructure of regenerated cellulose. The results may guide the manufacturing specifications of high-performance regenerated fiber materials.

Chiral metal-organic frameworks grown in situ for monolithic capillary electrochromatographic enantioseparation.

Chiral metal-organic frameworks (CMOFs) with chiral selectivity are one of the high-quality stationary phases for capillary electrochromatography (CEC). However, there is a problem of unsatisfactory enantioseparation performance of capillary columns due to insufficient loading. In this work, a lamellar CMOF (Cu-TC) was grown in situ on the surface of the monolith in a capillary monolithic column to obtain a Cu-TC@monolithic column. The CEC system constructed based on the Cu-TC@monolithic column shows a satisfactory chiral separation performance. Compared with the Cu-TC-based coated column (Cu-TC@coated column), the enantioseparation performance of the CEC system based on the Cu-TC@monolithic column was greatly improved, and the resolutions (Rs) of the model analytes were increased by 80-500%. In addition, the effects of experimental conditions such as the number of cycles of Cu-TC in situ growth, buffer concentration, buffer pH, organic solvent addition and applied voltage on the performance of CEC were also investigated. Finally, the chiral selection mechanism of the stationary phase was explored by selective adsorption experiments. The present work provides a new idea for the development of capillary stationary phases, which has great potential considering the diversity of CMOFs.

A thiol-ene mediated approach for peptide bioconjugation using 'green' solvents under continuous flow.

Flow chemistry has emerged as an integral process within the chemical sector permitting energy efficient synthetic scale-up while improving safety and minimising solvent usage. Herein, we report the first applications of the photoactivated, radical-mediated thiol-ene reaction for peptide bioconjugation under continuous flow. Bioconjugation reactions employing deep eutectic solvents, bio-based solvents and fully aqueous systems are reported here for a range of biologically relevant peptide substrates. The use of a water soluble photoinitiator, Irgacure 2959, permitted synthesis of glycosylated peptides in fully aqueous conditions, obviating the need for addition of organic solvents and enhancing the green credentials of these rapid, photoactivated, bioconjugation reactions.

Biomimetic Sol-Gel Chemistry to Tailor Structure, Properties, and Functionality of Bionanocomposites by Biopolymers and Cells.

Biosilica, synthesized annually only by diatoms, is almost 1000 times more abundant than industrial silica. Biosilicification occurs at a high rate, although the concentration of silicic acid in natural waters is ~100 μM. It occurs in neutral aqueous solutions, at ambient temperature, and under the control of proteins that determine the formation of hierarchically organized structures. Using diatoms as an example, the fundamental differences between biosilicification and traditional sol-gel technology, which is performed with the addition of acid/alkali, organic solvents and heating, have been identified. The conditions are harsh for the biomaterial, as they cause protein denaturation and cell death. Numerous attempts are being made to bring sol-gel technology closer to biomineralization processes. Biomimetic synthesis must be conducted at physiological pH, room temperature, and without the addition of organic solvents. To date, significant progress has been made in approaching these requirements. The review presents a critical analysis of the approaches proposed to date for the silicification of biomacromolecules and cells, the formation of bionanocomposites with controlled structure, porosity, and functionality determined by the biomaterial. They demonstrated the broad capabilities and prospects of biomimetic methods for creating optical and photonic materials, adsorbents, catalysts and biocatalysts, sensors and biosensors, and biomaterials for biomedicine.

Simple Air-Stable [3]Radialene Anion Radicals as Environmentally Switchable Catholytes in Water.

The hexacyano[3]radialene radical anion (1) is an attractive catholyte material for use in redox flow battery (RFB) applications. The substitution of cyano groups with ester moieties enhances solubility while maintaining redox reversibility and favorable redox potentials. Here we show that these ester-functionalized, hexasubstituted [3]radialene radical anions dimerize reversibly in water. The dimerization mode is dependent on the substitution pattern and can be switched in solution. Stimuli-responsive behavior is achieved by exploiting an unprecedented tristate switching mechanism, wherein the radical can be toggled between the free radical, a π-dimer, and a σ-dimer-each with dramatically different optical, magnetic, and redox properties-by changing the solvent environment, temperature, or salinity. The symmetric, triester-tricyano[3]radialene (3) forms a solvent-responsive, σ-dimer in water that converts to the radical anion with the addition of organic solvents or to a π-dimer in brine solutions. Diester-tetracyano[3]radialene (2) exists primarily as a π-dimer in aqueous solutions and a radical anion in organic solvents. The dimerization behavior of both 2 and 3 is temperature dependent in methanol solutions. Dimerization equilibrium has a direct impact on catholyte stability during galvanostatic charge-discharge cycling in static H-cells. Specifically, conditions that favor the free radical anion or π-dimer exhibit significantly enhanced cycling profiles.

Modified Ion Migration via Multi-Ion Competitive Transportation for Stable Aqueous Zn Metal Batteries.

The application of metal batteries is seriously affected by active ions transport and deposition stability during operation. This article takes water-based Zn metal electrodes as an example to analyze the factors that affect ion distribution and the impact of ion distribution on electrodeposition morphology through electrochemical model simulation calculation, in situ observation and electrochemical experiment: 1) high concentration will reduce the concentration polarization and the overpotential; 2) The passage of active ions through channels are facilitated by small anion (Cl-) rather than bigger one (SO4 2-), which means small deposition overpotential; 3) The transportability-reaction properties of cations (Zn2+, Li+, Na+ and H+) depends on their concentration, solvent coordination structure, and the energy changes during redox reactions. Based on the diffusion and reaction properties, a Li+ coupled Zn2+ electrolyte is designed to achieve the rapid transportation of doped ions to cover uneven growth sites and maintain a stable interface for the steady deposition of active Zn2+, guiding the interface design for high stability metal batteries in addition to the traditional addition of organic solvents.

Novel strategy for extraction and partitioning of phenol compounds from industrial residue of seriguela (Spondia purpurea L.) using aqueous two-phase systems

This work investigated the effect of different extracting agents on the extraction of phenolic compounds from agro-industrial residues of seriguela. Additionally, the phenolic compounds partitioning was studied using aqueous two-phase systems based on the extracting agents. The effect of the type of extracting agent such as water, organic solvent (1,3-dioxolane, acetone, 1,4-dioxane, and acetonitrile), and different ionic liquids (ILs) was evaluated. Afterward, solvent concentration, solid-liquid ratio, and time were analyzed in the extraction process. The solvent polarity played an important role in the extraction; thus 1,3-dioxolane (20 wt%), solid-liquid ratio 1:10 for 45 min was the best condition presented for organic solvents (1437.00 ± 0.01 mg L-1). On the other hand, [C2mim][CH3SO3] (20%), liquid-solid ratio 1:10 for 10 min was the best condition using IL (1842.56 ± 42.43 mg L-1). The mixture of water (60 wt%) + 1.3 dioxolane (20 wt%) + [C2mim][CH3SO3] (20 wt%) increased the concentration of phenolic compounds to 1894.22 ± 90.51 mg L-1. The phase separation was performed with the addition of organic solvent, reaching the mixture composition of 1,3-dioxolane (40 wt%) + [C2mim][CH3SO3] (10 wt%) + water (50 wt%) at 25 °C, allowing the recovery of the phenolic compounds (98.63 ± 0.15%) to the bottom phase (IL-rich phase) and a partition coefficient of 0.0092 ± 0.0002.