Type Of Co-solvent Research Articles

Photocatalytic Degradation of PCB 153 Using Fe3O4@SiO2@TiO2‐Co Core‐Shell Nanocomposite

AbstractThis study investigates the photocatalytic degradation of PCB 153 using Fe3O4@SiO2@TiO2‐Co core‐shell nanocomposites under LED irradiation. The unique core‐shell structure, incorporating a magnetic Fe3O4 core, a protective SiO2 layer, and a photoactive TiO2 shell doped with Co, enhances light absorption, charge separation, and stability. The effects of various parameters, including catalyst dosage, initial pollutant concentration, solution pH, H2O2 concentration, reaction time, and cosolvent type, were investigated to optimize the degradation process. The results demonstrated the high efficiency of the Fe3O4@SiO2@TiO2‐Co nanocomposite in degrading PCB 153, with a maximum degradation efficiency of 95.2% under optimal conditions. The magnetic properties of the Fe3O4 core enable easy separation and recovery of the catalyst, making it a sustainable and cost‐effective solution. This study provides valuable insights into the design and application of advanced photocatalysts for environmental remediation.

Cellulose Fiber with Enhanced Mechanical Properties: The Role of Co-Solvents in Gel-like NMMO System.

Cellulose has garnered attention in the textile industry, but it exhibits limitations in applications that require high strength and modulus. In this study, regenerated cellulose fiber with enhanced mechanical properties was fabricated from a gel-like N-methylmorpholine N-oxide (NMMO)-cellulose solution by modulating the intermolecular interaction and conformation of the cellulose chains. To control the interaction, two types of co-solvents (dimethyl acetamide (DMAc) and dimethyl formamide (DMF)) were added to the cellulose solutions at varying concentrations (10, 20, and 30 wt%). Rheological analysis showed that the co-solvents reduced the solution viscosity by weakening intermolecular interactions. The calculated distance parameter (Ra) in Hansen space confirmed that the co-solvent disrupted intermolecular hydrogen bonding within cellulose chains. The solutions were spun into fiber via a simple wet spinning process and were characterized by X-ray diffraction (XRD) and universal testing machine (UTM). The addition of co-solvent led to an increased crystallinity index (C.I.) owing to the extended cellulose chains. The modulus of the resulting fiber was increased when the co-solvent concentration was 10 wt%, regardless of the co-solvent type. This study demonstrates the potential for enhancing the mechanical properties of cellulose-based products by modulating the conformation and interaction of cellulose chains through the addition of co-solvent.

Towards Safer Li-Ion Batteries: A Study on Electrolyte Solvation and Dynamics with the Incorporation of Low Volatility Co-Solvents

Molecular dynamics (MD) simulations were employed to investigate how the content and type of co-solvents influence the solvation structure and transport properties of lithium ions (Li+) in electrolytes. Our focus was on lithium hexafluorophosphate (LiPF6) at a concentration of 1.0 M in a carbonate-based solvent composed of ethylene carbonate (EC) and dimethyl carbonate (DMC) with a 1:1 mixing ratio. Low-volatility co-solvents, including tetramethylene sulfone (TMS), dimethyl sulfoxide (DMSO), fluoroethylene carbonate (FEC), and succinonitrile (SN), were introduced into the electrolytic matrix at concentrations of 0, 10, 25, 50, 75, and 100 wt.%. Li+ dynamics were notably influenced by these factors. The highest Li+ transference number was observed at a 25 wt.% concentration for each co-solvent, particularly with 25 wt.% DMSO, resulting in the highest ionic conductivity (14.13 mS/cm) and Li+ transference number (0.47). In this system, the PF6 - anion refrains from joining the initial solvation shell of Li+. This is attributed to the higher donor number of DMSO compared to TMS, FEC, and SN, leading to a weakening of electrostatic interactions. These findings advance our comprehension of electrochemical principles in bulk electrolytes, providing insights for designing safer and more efficient lithium-ion batteries.

Properties of Chemically Stabilized Methanol–HVO Blends

Approximately 25% of global carbon emissions come from food production. Renewable fuels are crucial for curbing greenhouse gas (GHG) emissions from vehicles, non-road machines, and agricultural machinery. Tractors, key to modern farming, are central to these efforts. As agriculture strives for sustainability, alternative fuels like methanol and hydrotreated vegetable oil (HVO) are arousing interest because they are renewable and offer potential for blending for use in diesel engines. Methanol and HVO have limited solubility in direct mixing, so the addition of a co-solvent is essential. This study addresses the research gap regarding the properties of HVO and methanol blends with co-solvents. It investigated the impact of three co-solvents, 1-dodecanol, 1-octanol, and methyl butyrate, on the miscibility of HVO and methanol. The experimental measurements cross-varied the co-solvent type with different blending ratios (MeOH5 and MeOH10). Investigated parameters include fuel density, kinematic viscosity, distillation properties, and surface tension. The co-solvents enabled the formation of a singular, clear, and homogeneous phase in methanol-HVO blends. The co-solvent 1-dodecanol demonstrated the highest solubilizing capacity for MeOH5 and MeOH10 blends, followed by 1-octanol. Adding co-solvents led to increased fuel density, decreased kinematic viscosity, and small changes in surface tension. These findings contribute to the optimization of methanol–HVO fuel blends for efficient and environmentally friendly use in vehicles, non-road machinery, and agricultural machinery.

Cosolvent-assisted construction of high-performance reverse osmosis membranes with multilayer nanovoid structures: Effect of amides in aqueous phase

The cosolvent-assisted interfacial polymerization (CAIP) has garnered significant attention due to its capacity to easily and effectively modify the performance of polyamide (PA) reverse osmosis (RO) membranes. To gain deeper understanding of the mechanism of a specific type of cosolvents on the IP reaction, namely N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), and N,N-dimethylpropionamide (DMPr) were used as aqueous-phase cosolvents to systematically investigate their effects on the membrane structures and properties under different conditions. Amide cosolvents in the aqueous phase facilitated the diffusion of the amine monomer and the formation of nanovoids within the PA layer as the C-chain length of amides increased. When 1,2-dichloroethane was also included in the organic phase, the extent of the two-phase miscible zone was further increased with its assistance, which contributed to generating the larger nanovoids within the layer, thicker PA layer and extensive exterior PA layers, as well as significantly enhancing the water permeability and selectivity of membranes. Importantly, this study successfully prepared high-performance RO membranes with multilayer nanovoid structures in situ by introducing cosolvents in the IP reaction with permeability up to 2.26 L·m−2·h−1·bar−1, providing theoretical and experimental bases for further enrichment of CAIP.

Influences of Cosolvents and Antifreeze Additives Derived from Glycerol through Esterification on Fuel Properties of Biodiesel

Bioglycerol is a major by-product of the biodiesel manufacturing process. Various chemical derivatives from bioglycerol would enhance its economic value. An antifreeze of glycerine acetate was chemically converted from an esterification reaction of bioglycerol with acetic acid. The photocatalyst TiO2/SO42− irradiated with ultraviolet light assisted the chemical conversion reaction. The molar ratio of acetic acid/bioglycerol was varied to obtain the optimum composition of the derived antifreeze product. Different cosolvents were considered to enhance the homogeneous extent between the antifreeze of glycerine acetate and biodiesel, and thus, the anti-freezing effect. The cosolvent/glycerine acetate, at various volumetric ratios from 0 to 0.25 vol.%, was blended into a commercial biodiesel. After 5 vol.% antifreeze of the glycerine acetate/cosolvent mixture of the biodiesel was added to the commercial biodiesel, the fuel properties of the biodiesel were analyzed. The effects of the cosolvent types and the blended volumetric ratio of cosolvent to the antifreeze of glycerine acetate on the fuel properties of the commercial biodiesel were analyzed to determine the optimum cosolvent type and volumetric composition of the cosolvent/glycerine acetate. The experimental results show that the antifreeze of glycerine acetate produced from the reaction of acetic acid/glycerol at a molar ratio equal to 8 under UV-light irradiation appeared to have the lowest freezing point. The UV-light irradiation on the TiO2/SO42− catalyst also caused higher triacylglycerol (TAG) and diacylglycerol (DAG) and lower monoacylglycerol (MAG) formation. In addition, the low-temperature fluidity was the most excellent when the volumetric percentage of the methanol/glycerine acetate was equal to 0.25 vol.%, at which the cold filter plugging point (CFPP) of the biodiesel was reduced from 3 °C for the neat biodiesel to −2 °C for the biodiesel blended with the mixture. In contrast, the effect of adding the antifreeze on the CFPP of the biodiesel was inferior; it was reduced from 3 °C for the neat biodiesel to 1 °C for the biodiesel when butanol cosolvent was added. The increase in the volumetric ratio of cosolvent/antifreeze increased the acid value and cetane index while it decreased the kinematic viscosity and CFPP. The heating value was observed to increase for butanol while decreasing for methanol with the increase in the volumetric ratio of cosolvent/antifreeze. In comparison to butanol, the cosolvent methanol caused a higher cetane index and acid value but a lower kinematic viscosity, heating value, and CFPP of the blended commercial biodiesel.

Enzyme-Assisted Supercritical Fluid Extraction of Flavonoids from Apple Pomace (Malus×domestica).

Herein an enzyme-assisted supercritical fluid extraction (EA-SFE) was developed using the enzyme mix snailase to obtain flavonols and dihydrochalcones, subgroups of flavonoids, from globally abundant waste product apple pomace. Snailase, a commercially available mix of 20-30 enzymes, was successfully used to remove the sugar moieties from quercetin glycosides, kaempferol glycosides, phloridzin and 3-hydroxyphloridzin. The resulting flavonoid aglycones quercetin, kaempferol, phloretin and 3-hydroxyphloretin were extracted using supercritical carbon dioxide (scCO2) and minimum amounts of polar cosolvents. A sequential process of enzymatic hydrolysis and supercritical fluid extraction was developed, and the influence of the amount of snailase, pre-treatment of apple pomace, the time for enzymatic hydrolysis, the amount and type of cosolvent and the time for extraction, was studied. This revealed that even small amounts of snailase (0.25 %) provide a successful cleavage of sugar moieties up to 96 % after 2 h of enzymatic hydrolysis followed by supercritical fluid extraction with small amounts of methanol as cosolvent, leading up to 90 % of the total extraction yields after 1 h extraction time. Ultimately, a simultaneous process of EA-SFE successfully demonstrates the potential of snailase in scalable scCO2 extraction processes for dry and wet apple pomace with satisfactory enzyme activity, even under pressurized conditions.

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.

A comparative study on fluorescent performance of several heterocyclic dyes: In aqueous solution or immobilized on zirconia nanotube arrays

The solution pH values, cosolvent type, and immobilization of the fluorescent dyes affect their dispersion state and fluorescent performance significantly. Zirconia, with abundant resources, low cost and high refractive index, is a commonly used immobilization material for fluorescent dyes. In this paper, zirconia nanotube array films (ZNAF) prepared by anodic oxidation method were used as immobilization materials for common heterocyclic dyes (fluorescein, rhodamine B, acridine, acridine orange). A systematically comparative study on their fluorescent performance of aqueous solutions at different pH values with or without cosolvent sodium benzenesulfonate and of immobilization films with ZNAF as carriers was investigated. Moreover, the performances of acridine orange-rhodamine B fluorescence resonance energy transfer (FRET) system with different dispersion states were studied in detail. Results demonstrate that the solution pH values, immobilization and sodium benzenesulfonate have great influence on the performance of these fluorescent dyes, and the change rules of different fluorescent molecules are obviously different, which is closely related to their molecular structure and dispersion state. Compared with aqueous solutions, the fluorescence emission of acridine orange and rhodamine B is greatly improved by immobilization, which is 8.6 and 5.4 times higher than the original, respectively. Furthermore, energy transfer efficiency (E) and enhancement ratio of the acridine orange-rhodamine B system are significantly increased by loading it on ZNAF, with a maximum E value of 84.8% (pH = 13) and a maximum enhancement ratio of 5.27 (pH = 5).

Thermodynamic study of choline chloride-based deep eutectic solvents with dimethyl sulfoxide and isopropanol

The thermodynamic properties of four binary mixtures of deep eutectic solvent (DES), i.e., ChCl/Gly (choline chloride + glycerol at a molar ratio of 1:2) and ChCl/EG (choline chloride + ethylene glycol at a molar ratio of 1:2) with two common co-solvents, i.e., dimethyl sulfoxide (DMSO) and isopropanol (IPA), were studied. Density and viscosity were determined at temperatures from 288.15 to 323.15 K, while measuring the enthalpy of mixing was performed at 308.15 and 318.15 K. The volumetric properties (i.e., excess molar volume and excess partial molar volume) and excess viscosities (i.e., viscosity deviation and logarithmic excess viscosity) were further calculated to investigate the effects of temperature, types of co-solvent and DES, and their contents on the non-ideal behavior of these systems, where the influence of treating the DES as a mixture of two components or a pseudo-component was discussed. The results of volumetric properties indicate that the combined influence of packing effects and H-bonding interactions between the DES and co-solvents led to the contraction of mixture volume, and the results of excess viscosities show H-bonding interactions play an important role in their variations. The results of enthalpy of mixing show that the mixing of DES with IPA is endothermic, while the mixing of DES with DMSO is exothermic. Furthermore, the nonrandom two-liquid (NRTL) model and Gibbs-Helmholtz equation were combined to represent the experimental results of the enthalpy of mixing, and the total average relative deviation (ARD) of all studied systems is 5.43%.

From Diazonium Salts to Optically Active 1‐Arylpropan‐2‐ols Through a Sequential Photobiocatalytic Approach

AbstractThe photocatalytic Meerwein arylation between aromatic diazonium salts and isopropenyl acetate under blue LED light irradiation in aqueous medium has been deeply investigated. Optimization of the reaction conditions in terms of substrate concentration, ester equivalents, cosolvent type and amount, reaction time and photocatalyst source, has allowed the access to a variety of 1‐arylpropan‐2‐ones with yields up to 95% using 9‐mesityl‐10‐methylacridinium perchlorate ([Acr‐Mes]ClO4). Next, the design of a one‐pot sequential photobiocatalytic linear approach was accomplished, by the combination of the Meerwein arylation with the bioreduction of the corresponding ketone intermediates. Thus, a total of 19 pairs of 1‐arylpropan‐2‐ol enantiomers were obtained depending on the alcohol dehydrogenase stereopreference. Global yields up to 76% were attained with high to excellent stereoselectivity (90 to >99% ee). Also, it was possible to get access to both 1‐phenylpropan‐2‐ol antipodes (51–53% yield) starting from aniline through a one‐pot three‐step sequential photobiocatalytic protocol.

Investigation of feasibility of alkali–cosolvent flooding in heavy oil reservoirs

Cold production is a challenge in the case of heavy oil because of its high viscosity and poor fluidity in reservoir conditions. Alkali–cosolvent–polymer flooding is a type of microemulsion flooding with low costs and possible potential for heavy oil reservoirs. However, the addition of polymer may cause problems with injection in the case of highly viscous oil. Hence, in this study the feasibility of alkali–cosolvent (AC) flooding in heavy oil reservoirs was investigated via several groups of experiments. The interfacial tension between various AC formulations and heavy crude oil was measured to select appropriate formulations. Phase behavior tests were performed to determine the most appropriate formulation and conditions for the generation of a microemulsion. Sandpack flooding experiments were carried out to investigate the displacement efficiency of the selected AC formulation. The results showed that the interfacial tension between an AC formulation and heavy oil could be reduced to below 10−3 mN/m but differed greatly between different types of cosolvent. A butanol random polyether series displayed good performance in reducing the water–oil interfacial tension, which made it possible to form a Type III microemulsion in reservoir conditions. According to the results of the phase behavior tests, the optimal salinity for different formulations with four cosolvent concentrations (0.5 wt%, 1 wt%, 2 wt%, and 3 wt%) was 4000, 8000, 14000, and 20000 ppm, respectively. The results of rheological measurements showed that Type III microemulsion had a viscosity that was ten times that of water. The results of sandpack flooding experiments showed that, in comparison with waterflooding, the injection of a certain AC formulation slug could reduce the injection pressure. The pressure gradient during waterflooding and AC flooding was around 870 and 30–57 kPa/m, respectively. With the addition of an AC slug, the displacement efficiency was 30%–50% higher than in the case of waterflooding.

The critical impacts of anion and cosolvent on morpholinium ionic liquid pretreatment for efficient renewable energy production from triticale straw

Morpholinium ionic liquids (ILs) using N-allyl-N-methylmorpholinium ([AMMorph]) cation in combination with acetate ([OAc]), formate ([OFo]), carbonate ([CO3]), and sulfate ([SO4]) anions were used for the pretreatment of triticale straw. The pretreatment was performed with various percentages of IL as well as water and dimethyl sulfoxide (DMSO) as cosolvents. These cosolvents reduced IL consumption and increased the ethanol efficiencies up to 90% and 76% after pretreatment with [AMMorph][OAc] or [AMMorph]2[CO3], respectively, and water cosolvent. Whereas the mixture of water and DMSO resulted in the maximum ethanol yields of 82% and 69% for [AMMorph][OFo] and [AMMorph]2[SO4], respectively. Among the studied IL-cosolvent combinations, the best solvent for the pretreatment of triticale straw was a mixture of [AMMorph][OAc] with 20% water to achieve highest ethanol production. The performance of this IL was further studied in terms of temperature and time, resulting in hydrolysis and ethanol yields of 99% and 94%, respectively. The results revealed that the anion plays a key role in the pretreatment efficiency and the organic anions, i.e., acetate and formate, had better performance in the presence of cosolvent compared with inorganic anions. Moreover, the amount and type of cosolvent for obtaining the highest yields are highly dependent on the anion type.

Carbon dioxide expanded liquid: an effective solvent for the extraction of quercetin from South African medicinal plants

BackgroundQuercetin is one of the most important bioflavonoids having positive effects on the biological processes and human health. Typically, it is extracted from plant matrices using conventional methods such as maceration, sonication, infusion, and Soxhlet extraction with high solvent consumption. Our study aimed to optimize the environmentally friendly carbon dioxide-based method for the extraction of quercetin from quince fruit with an emphasis on extraction yield, repeatability, and short extraction time.ResultsA two-step design of experiments was used for the optimization of the key parameters affecting physicochemical properties, including CO2/co-solvent ratio, co-solvent type, temperature, and pressure. Finally, gas expanded liquid combining CO2/ethanol/H2O in a ratio of 10/81/9 (v/v/v) provided the best extraction yield. Extraction temperature 66 °C and pressure 22.3 MPa were the most suitable conditions after careful optimization, although both parameters did not significantly affect the process. It was confirmed by experiments in various pressure and temperature conditions and statistical comparison of obtained data. The optimized extraction procedure at a flow rate of 3 mL/min took 30 min. The repeatability of the extraction method exhibited an RSD of 20.8%.ConclusionsThe optimized procedure enabled very fast extraction in 30 min using environmentally friendly solvents and it was successfully applied to 16 different plant samples, including 14 bulbs and 2 fruits from South Africa. The quercetin content in extracts was quantified using ultra-high performance liquid chromatography (UHPLC) with tandem mass spectrometry. UHPLC hyphenated with high-resolution mass spectrometry was used to confirm chemical identity of quercetin in the analyzed samples. We quantified quercetin in 11 samples of all 16 tested plants. The quercetin was found in Agapanthus praecox from the Amaryllidaceae family and its presence in this specie was reported for the first time.Graphical

Assessing Peroxygenase-Mediated Oxidations in the Presence of High Concentrations of Water-Miscible Co-Solvents

The use of water-miscible organic co-solvents in biocatalysis is a simple procedure for obtaining higher enzymatic activities toward hydrophobic substrates. However, effects on activity and stability have to be carefully evaluated, also with regard to the type and concentration of the respective co-solvent. In this contribution, we investigated and evaluated the effect of some common water-miscible co-solvents on the biocatalytic performance of the recombinant unspecific peroxygenase rAaeUPO from Agrocybe aegerita. rAaeUPO showed promising activities in the presence of high concentrations of the best co-solvent acetonitrile, which enabled to use higher substrate concentrations (≥100 mM). Employing high acetonitrile concentrations for UPO-mediated oxidation of ethylbenzene to (R)-1-phenylethanol was demonstrated under preparative scale conditions and led to product accumulation rates of 31 mM h−1.

Extraction of moringa essential oil (Moringa Oleifera) with conventional solvents and supercritical fluid / Extração do óleo essencial de moringa (Moringa Oleifera) usando solventes convencionais e fluído supercrítico

Essential oils (EO) are substances extracted from different parts of plants and have specific characteristics that guarantee their application in different processes. EO extraction processes involve different methods. Among the methods mentioned in the literature, those related to the minimization of effluent production rates are commonly used. In this context, studies were conducted on the extraction of essential oil from the seed of Moringa Oleífera, using a mixture of carbon dioxide (supercritical fluid) and ethanol or acetone (conventional fluids) as a solvent, to evaluate the influence of the flow rates of fluid mixture flow. Several experiments have demonstrated that the process performance is strongly dependent on the flow velocity of the fluid mixture and the type of co-solvent used. In this case, the decrease in CO2 flow velocity increases the residence and contact time between the fluid and solid particles. The ethanol is more effective than acetone, mainly due to its intrinsic physical properties. The relationship described above results in the highest diffusion rate of the solute contained in the solid pores to the fluid mixture. The results obtained from these studies are similar to those in the literature and can support scale-up models of the process that aim to enhance the development and proposition of essential oils to meet the country's needs, supported by the use of biomass produced in Angola.

Bioinks Enriched with ECM Components Obtained by Supercritical Extraction.

Extracellular matrix (ECM)-based bioinks have been steadily gaining interest in the field of bioprinting to develop biologically relevant and functional tissue constructs. Herein, we propose the use of supercritical carbon dioxide (scCO2) technology to extract the ECM components of cell-sheets that have shown promising results in creating accurate 3D microenvironments replicating the cell’s own ECM, to be used in the preparation of bioinks. The ECM extraction protocol best fitted for cell sheets was defined by considering efficient DNA removal with a minor effect on the ECM. Cell sheets of human dermal fibroblasts (hDFbs) and adipose stem cells (hASCs) were processed using a customised supercritical system by varying the pressure of the reactor, presence, exposure time, and type of co-solvent. A quantification of the amount of DNA, protein, and sulfated glycosaminoglycans (sGAGs) was carried out to determine the efficiency of the extraction in relation to standard decellularization methodologies. The bioinks containing the extracted ECM were fabricated by combining them with alginate as a support polymer. The influence of the alginate (1%, 2% w/vol) and ECM (0.5% and 1.5% w/vol) amounts on the printability of the blends was addressed by analysing the rheological behaviour of the suspensions. Finally, 3D printed constructs were fabricated using an in-house built extrusion-based bioprinter, and the impact of the extrusion process on cell viability was assessed. The optimised scCO2 protocol allowed efficient removal of DNA while preserving a higher number of proteins and sGAGs than the standard methodologies. The characterization of extract’s composition also revealed that the ECM produced by hDFbs (fECM) and hASCs (aECM) is distinctively affected by the extraction protocols. Furthermore, rheological analysis indicated an increase in viscosity with increasing ECM composition, an effect even more prominent in samples containing aECM. 3D printing of alginate/ECM constructs demonstrated that cell viability was only marginally affected by the extrusion process, and this effect was also dependent on the ECM source. Overall, this work highlights the benefits of supercritical fluid-based methods for ECM extraction and strengthens the relevance of ECM-derived bioinks in the development of printed tissue-like constructs.

Investigation of aqueous and organic co-solvents roles in fabricating seawater reverse osmosis membrane

The addition of co-solvents in aqueous or organic phases of interfacial polymerization is a feasible strategy to tune the performance of aromatic polyamide (PA) thin-film composite (TFC) membrane for brackish water desalination, however, limited progress has been made in developing co-solvent-tailored seawater reverse osmosis (SWRO) membrane. Herein, SWRO membranes were prepared by adding various types of aqueous and organic co-solvents to reveal their impacts on the formation of the PA crumples. It was found that the aqueous/organic co-solvents affected the solubility parameter distance and interfacial tension between two immiscible phases, facilitating the diamine diffusion rate and resulting in a significant change in PA structure. The PA layer with modulated microstructure and varied surface features such as widened void structure, rougher surface, better wettability, and controlled cross-linking degree can be derived from the high interfacial instability that existed between the co-solvent and initial PA film due to the close mutual affinity. Besides, the additional polyvinyl alcohol coating layer atop the PA membrane successfully further enhanced the membrane selectivity. Overall, the mechanistic insights attained in this study revealed the relationship of diamine diffusion, physicochemical properties of PA layer and membrane separation performance for co-solvent-assisted membrane fabrication to render resultant SWRO membrane with more comparable permselectivity. The optimized TFC-SWRO membranes exhibited pure water permeability of 2.2 and 3.2 L m −2 h −1 bar −1 upon the assistance of aqueous and organic co-solvents, respectively, while maintaining excellent NaCl rejection of approximately 99% under seawater desalination tests. ✓ Aqueous or organic co-solvents were used aiming to flexibly design high-performance SWRO membrane. ✓ The synergistic impacts of solubility parameter and interfacial tension were established to elucidate diamine diffusion behavior. ✓ The relationship of “monomer diffusion - structure property - separation performance” was elaborated. ✓ The formation of a PVA coating layer enhanced the selectivity of co-solvent-assisted SWRO membrane.

Production of biodiesel from salvia mirzayanii oil via electrolysis using KOH/Clinoptilolite as catalyst.

In recent years, fossil fuels are the main energy supply in both transportation and industry. Their increasing consumption has been causing global warming and acid raining. One of the alternative fuels that is considered today is biodiesel, which is clean and eco-friendly. The main method for biodiesel production is transesterification reaction of triglyceride oil with methanol in the presence of a suitable catalyst. In this research, biodiesel was produced from Salvia mirzayanii oil in the presence of KOH/Clinoptilolite catalyst. The impregnation, hydrothermal, and incipient wetness methods were used for loading KOH on the Clinoptilolite support to produce biodiesel via electrolysis method. The characteristics of the KOH/Clinoptilolite catalyst were examined through scanning electron microscopy (SEM), energy dispersive X-ray Spectroscopy (EDX), X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET) analyses. The effects of key parameters including catalyst amount, methanol to oil molar ration, reaction time, reaction temperature, co-solvent type and its proportion, electrolysis voltage, catalyst reusability, and KOH concentration were examined on the biodiesel yield. The results of elemental analysis confirmed that KOH was well loaded on Clinoptilolite support. The highest yield of biodiesel was obtained 79% in the presence of 10wt% catalyst, alcohol to oil ratio of 9:1, acetone concentration of 10wt%, temperature of 60°C, and voltage of 10V. The results of GC-MS, FTIR and H-NMR analyses illustrated that biodiesel as a product was produced with good quality. Based on the obtained results, in all three methods of catalyst synthesis KOH was loaded on Clinoptilolite support but at the end of the transesterification reaction only the catalyst synthesis via incipient wetness method could be reused three times under optimum reaction conditions. The produced biodiesel had high quality, whose physical and chemical properties had good agreement with ASTM, EN 14214, IS 15607 standards. Since the salvia mirzayanii oil is an appropriate feedstock source for biodiesel production, it is suggested to use salvia mirzayanii oil and KOH/Clinoptilolite catalyst to produce biodiesel on industrial scale.

EOR Perspective of microemulsions: A review

Since conventional oil recovery techniques only produce a limited fraction of the original oil in place (OOIP), the need for Enhanced Oil Recovery (EOR) methods has become imperative. Chemical enhanced oil recovery (cEOR) techniques have been widely studied for decades. Surfactants are frequently employed in cEOR processes. Micelles are formed when the amount of surfactant exceeds the critical micelle concentration (CMC) by aggregation of monomers; this can potentially result in the formation of microemulsions when the surfactant solution comes in contact with reservoir fluids. These microemulsions are homogenous and thermodynamically stable. This review focuses on factors affecting the formation of microemulsions such as pressure, temperature, salinity, nature of cosurfactants, cosolvent type and concentration, water-oil-ratio, pH, and oil properties. This review also covers the characterization of microemulsions, such as via: phase behavior and rheological properties, visual inspections, polarized light microscopy studies, their interfacial, surface tension, and zeta potential measurement plus investigations of the particle size distributions. Finally, a comprehensive review of surfactant systems that have been used to generate microemulsions at different reservoir conditions is presented. This review reveals that anionic surfactants are capable of generating a Winsor III type microemulsion – which is optimal in EOR processes. On the other hand, cationic surfactants usually do not exhibit Winsor III type behavior, and nonionic surfactants are normally only applicable as cosurfactants in EOR contexts.