Water Mixtures Research Articles

Energy expenditure in the Z-type plate heat and mass exchanger based on the concept of heat-integrated distillation column

Thermal separation of substances typically involves the use of rectification columns equipped with condensers and reboilers. This conventional method is notably energy-intensive, necessitating substantial heat input to the reboiler and leading to significant waste heat discharge through the condenser into the environment. This paper presents our further study on an innovative alternative technology for thermal separation. The proposed approach involves conducting thermal separation within flow channels of a Heat and Mass Exchanger (HME), which are composed of plates with intricate geometries. In this system, heat distribution is maintained through the diaphragm, i.e., the channel walls, facilitating both heat exchange and simultaneous thermal separation of substances.This paper focuses on both laboratory and numerical investigations of two-phase flow within various channel geometries. Experimentally, four distinct channel designs were examined using an air–water mixture, aiming to identify a new geometry that facilitates countercurrent flow patterns in this challenging substance combination. The experimental phase led to the selection of a channel geometry that demonstrated the most effective countercurrent flow for intensive cases, then used for ethane-ethylene mixture. Subsequently, this selected geometry was subjected to numerical calculations using the mathematical model of the Heat and Mass Exchanger (HME). These calculations encompassed flow dynamics, thermal behavior, and the sizing of the HME, tailored specifically for the newly identified channel geometry.

Long-Term Estimation of Depositions on Heating Surface During Boiling of Long-Life Coolant

Abstract Long-term boiling experiments with long-life coolant have been made with the aim to apply a boiling cooling technology to the next generation high exothermic electronic devices. The long-life coolant commonly used for cooling electronic devices is a mixture of ethylene glycol and water with multiple antirust inhibitors as additives, which may result in some depositions on the heat transfer surface during the boiling. In this study, the heat transfer surface made of copper was set vertically, and long-term experiments have been performed under the pool boiling. The deposition process was monitored for constant heating conditions. From experimental results, a distinct surface temperature change was observed under constant heat flux conditions. Just after keeping constant heat flux, the surface temperature increases with time, a certain time later decreases, and finally takes a stable value. During the temperature rise, the deposition adheres to the heat transfer surface in dots, which may cause an increase in thermal resistance between the wall surface and the working fluid. However, during the temperature drop, large growth of dot-like depositions on the heat transfer surface could alter wettability and surface roughness, enhancing boiling heat transfer. In addition, to investigate the characteristics of the depositions adhered to the heat transfer surface, a component analysis has been performed, which shows that the main substance was strontium hydroxyapatite, which might be formed by chemical reaction between components in the additives under the boiling.

Experimental and Theoretical Investigation of Thermal Parameters Influencing the Freezing Process of Ice Cream

Freezing time stands out as the most critical parameter in ice cream production, significantly influencing the final product’s quality and production efficiency. Therefore, it is essential to accurately estimate the freezing time based on ice cream recipes. This research paper focuses on determining the thermal properties of ice cream samples by leveraging insights from previous studies. Moreover, a new specific heat correlation is proposed to account for the latent heat effect of water during the freezing process. The results demonstrated that the new specific heat correlation aligns well with established formulas from previous research as well as experimental results with maximum 2.5% deviation. To validate the accuracy of the proposed numerical model, experimental studies were compared with numerical results for the first time in the context of ice cream freezing inside a mold. Additionally, a parametric analysis was conducted using numerical modelling to discern the relative importance of various production process parameters. Notably, the glycol–water mixture temperature emerged as the most influential parameter affecting freezing time, while the amount of air inside the ice cream was identified as the least significant factor.

Comparison between acetonitrile-water separation by betaine and betaine hydrochloride

Acetonitrile and water are miscible solvents. This study compares their separation by betaine and betaine hydrochloride. Acetonitrile is a hydrogen (H) bond acceptor and so is betaine, because of its -CO and -CO- groups. Therefore, betaine competes with acetonitrile for interactions with the hydrogens of water molecules, as indicated by attenuated total reflectance - Fourier transform infrared spectroscopy (ATR-FTIR). Therefore, when added to acetonitrile-water mixtures, betaine displaces acetonitrile. Separation into bulk phases occurs with 5–10 wt% betaine (relative to water), for acetonitrile concentrations between 50 and 80 wt% (relative to the aqueous phase). At lower acetonitrile concentrations (e.g., 1 wt%), betaine separates acetonitrile from water to yield emulsified acetonitrile droplets, detected by light scattering. With 1 wt% acetonitrile and betaine, acetonitrile droplets in water are negatively charged due to the -CO- group of betaine, as shown by electrophoretic measurements. In the case of betaine hydrochloride, the negative charge of the -CO- group is shielded by a proton, and interactions with water are weaker. As a result, bulk separation is not observed. Nonetheless, betaine hydrochloride also competes against acetonitrile for interactions with hydrogen atoms of water molecules, albeit not as effectively as betaine. This is shown by ATR-FTIR. Therefore, betaine hydrochloride emulsifies acetonitrile in water into sub-micron droplets. These droplets are positively charged, owing to the positively charged nitrogen atom of betaine hydrochloride. Acidifying mixtures of betaine, acetonitrile and water (with HCl) impedes bulk separation. This result confirms the importance of electrostatic interactions between the hydrogens of water and the unshielded, negative -CO- group of betaine.

Hydrogel Coated Mesh with Controlled Flux for Oil/Water Separation.

Superwetting surfaces are often applied in oil/water separation. Hydrogels have been widely prepared as superhydrophilic/underwater superoleophobic materials for oil/water separation since they are naturally hydrophilic. Hydrogels usually need to be combined with porous substrates such as stainless steel mesh (SSM) due to their poor mechanical properties. However, it is usually inevitable that the pores of the substrate are clogged during the actual preparation process, leading to a significant decrease in the flux, which limits its effective application. In this study, acrylic acid (AA), chitosan (CS) and modified silica were utilized to form a layer of dual-network PAA/CS@SiO2 hydrogel by photopolymerization on SSM, followed by a simple and novel ultrasonic-assisted pore-making method to generate numerous pores in situ on the surface of the hydrogel-coated mesh, which led to an increase in water flux from 0 to 70,000 L m-2 h-1 without decreasing the separation efficiency. After 100 separations of a mixture of n-hexane and water, the flux was still higher than 50,000 L m-2 h-1 with a separation efficiency above 99%, which is superior to most of hydrogel-coated meshes reported so far. Moreover, the prepared PAA/CS@SiO2 hydrogel-coated mesh also has good environmental stability, low swelling, and self-cleaning properties. We believe that the strategy of this study will provide a simple new perspective when hydrogels block the substrate pores, resulting in low water flux.

An activity coefficient model for mixed-solvent electrolyte mixtures based on Gibbs–Duhem’s equation: A case study of mixtures of water, KCl and ethanol

Thermodynamic properties of mixtures with several fluid components and electrolytes are challenging to model. Models are needed to develop and improve a wide range of electrochemical systems such as fuel cells, lithium-ion batteries, and processes with ion-exchange membranes. In the literature, activity coefficients are extracted using fundamentally different experimental methods that rely on electrochemical cells, vapour pressure measurements, solubility measurements, etc. The reference states of the activity coefficients obtained from these methods are likely to differ. This makes it difficult to combine or compare activity coefficient models from different sources. In this work, we present a method using Gibbs–Duhem’s equation for the development of activity coefficient models of mixtures that are based on experimental data from different methods. We use the ternary mixture of KCl, H2O and ethanol as example. First, empirical expressions are developed for the logarithm of the activity coefficients of KCl and ethanol. The expression for the activity coefficient of H2O is next derived using Gibbs–Duhem’s equation. The resulting three activity coefficient models are fitted to available experimentally data from several sources, generating linear and relatively low-complexity activity coefficient models. The empirical activity coefficient models are next compared to the electrolyte cubic plus association (e-CPA) equation of state. The models give saturation pressures in ternary mixtures that have average absolute relative deviations for water/ethanol of 8.3/3.4% for the empirical model and 11.8/3.3% for e-CPA. Experimental data reduction procedures for concentration cells, formation cells, and vapour pressure measurements are discussed, and the freedom to choose the reference state and the consequences are highlighted.

Droplet Velocity Measurement Of Acetone-Water Spray Using Fluorescence-Based Particle Image Velocimetry

A method for measuring the velocity of liquid droplets emanating from an effervescent injector into ambient air was experimented using a mixture of acetone and water. Conventional methods such as Laser Doppler Velocimetry and Particle Image Velocimetry, which utilise Mie-scattering, have limitations due to multiple scattering and strong surface reflections, respectively. In the current study, we demonstrate fluorescence-based particle image velocimetry, which can overcome the abovementioned difficulty. Unlike previous similar studies that used fluorescent dyes, the inherent fluorescence of acetone is utilised in our strategy. The acetone and water were mixed in different volume ratios, and the effervescent jet was produced with air. The Gas-to-Liquid ratio of 8% was considered in this study. The spray droplets were excited using the fourth harmonic of the Nd-YAG laser. Two acetone Planar Laser laser-induced fluorescence images are acquired with a CCD camera and with a 20 µs time difference. The velocity vectors are obtained based on the cross-correlation between the two images. The results showed that absorption greatly influences the estimated velocity distribution. At a low acetone concentration, the velocity distribution became uniform around the jet centre line. A high-intensity laser could improve the velocity estimate in the core of the aerated jet. The proposed method can be applied directly to ambient and pressurised conditions where wall scattering is dominant. The directional independence of the fluorescence is also an advantage in scenarios where the imaging angle is a constraint.

Photo-responsive anticounterfeiting inks switching between colorless and cyan/magenta/yellow for flexible, full-color, and large-area printing

Inkjet printing of photo-responsive patterns capable of switching between colorless and full-color is regarded as an innovative anticounterfeiting technique with a higher security level. Therefore, colorless inks which can be changed to cyan (C), magenta (M), and yellow (Y) upon photochromism are highly required. Herein, three photochromic (PC) inks C, M, and Y switching between colorless and cyan/magenta/yellow, respectively, have been successfully prepared by dissolving viologen derivatives AV, AEV, and NOV in solvent mixtures of water, ethanol, and ethylene glycol, with sodium dodecyl sulfate (SDS) as surfactant. With a mass fraction of 0.5 wt% for SDS, an optimal rheological property with a viscosity of 3.48 mPa·s, a contact angle of 29.4° on poly (ethylene terephthalate) (PET) substrate, a surface tension of 23.16 mN m−1, and a Z value of 3.85, is realized for ink C. Under the same conditions, inks M and Y are prepared and display suitable rheological properties for inkjet printing. The films are invisible initially and become colorful upon UV irradiation with no significant decay after 20 repetitive PC switching. Subsequently, various colorful patterns with high resolutions were printed on conventional A4 paper and become visible only after irradiation by a UV lamp. Therefore, these photo-responsive tricolor inks can be used in anticounterfeiting field and two practical examples of a stamp and a personal check with cryptical texts and color information have been demonstrated. Overall, the developed photo-responsive C/M/Y inks can be utilized in flexible, full-color, and large-area printing, providing a novel approach towards innovative anticounterfeiting technology.

Compact 3D-Printed Unit for Separation of Simple Gas Mixtures Combined with Chemiresistive Sensors.

Inexpensive chemiresistive sensors are often insufficiently selective as they are sensitive to multiple components of the gas mixture at the same time. One solution would be to insert a device in front of the sensor that separates the measured gas mixture and possibly isolates the unwanted components. This study focused on the fabrication and characterization of a compact unit, which was fabricated by 3D printing, for the separation and detection of simple gas mixtures. The capillary, the basic part of the compact unit, was 4.689 m long and had a diameter of 0.7 mm. The compact unit also contained a mixing chamber on the inlet side and a measuring chamber with a MiCS-6814 sensor on the outlet side. Mixtures of ethanol and water at different concentrations were chosen for characterization. The measured calibration curve was found to have a reliability of R2 = 0.9941. The study further addressed the elements of environmental friendliness of the materials used and their sustainability.

Understanding the structures and interactions in gaseous mixtures of water-alcohol by high-resolution infrared spectroscopy

Interactions of water and chemical or bio-compound have a universal concern and have been extensively studied. For spectroscopic analysis, the complexity and the low resolution of the spectra make it difficult to obtain the spectral features showing the interactions. In this work, the structures and interactions in gaseous water and water-alcohol mixtures were studied using high-resolution infrared (HR-IR) spectroscopy. The spectral features of water clusters of different sizes, including dimer, trimer, tetramer and pentamer, were observed from the measured spectra of the samples in different volume concentrations, and the interactions of water and methanol/ethanol in the mixtures were obtained. In the analysis, a method based on principal component analysis was used to separate the overlapping spectra. In water-alcohol mixtures, when water is less, water molecules tend to interact with the OH groups on the exterior of the alcohol aggregate, and with the increase of water, a water cage forms around the aggregates. Furthermore, the ratio of the molecule number of methanol in the aggregate to that of water in the cage is around 1:2.3, and the ratio for ethanol is about 1:3.2.

Determination of ionization/protonation constant values of some guanine derivative drugs by traditional/ green RPLC and UV–Vis spectrophotometric methods

In this study, the greenreverse-phase liquid chromatography (RPLC) method was used in addition to the traditional RPLC method to determine the ionization/protonation constants (pKa) of the guanine derivatives ganciclovir, valacyclovir, and valganciclovir. The determination of these values was carried out in binary acetonitrile–water mixtures (for the traditional RPLC method), ethanol–water binary mixtures (for the green RPLC method), and in aqueous solution of a micelle-forming surfactant (for pure micellar chromatography). The pKa values sspKa of the compounds were calculated using the linear solvation energy relationship (LSER) method in the studied hydro-organic and micellar solvent-free mixtures. Moreover, the UV–Vis spectrophotometric method was used to compare the sspKa values of ganciclovir, valaciclovir, and valganciclovir obtained in a acetonitrile–water medium using another method. The pKa values ​​of the examined compounds in water were calculated using the linear relationship between the sspKa values ​​determined in hydroorganic mixtures and some macroscopic values ​​of acetonitrile and ethanol. Additionally, wwpKa values ​​were determined in the micellar solvent-free mobile phase. Subsequently, the wwpKa values calculated by these direct and indirect methods were compared and the agreement between them was excellent. By using the wwpKa value calculated for each compound, the ionization percentages were calculated at different pH (1–12) values with the Henderson-Hasselbalch equation. The environmental impact of the RPLC methods used in this study was assessed using the green metrics tools GAPI and AGREE. The result of the investigation was that the environmental suitability of the green methods is satisfactory.

Study on the unheated gathering boundaries of crude oil during high water content period in cold region

The energy consumption of oil gathering and transportation can be effectively reduced by using an unheated gathering process in oilfields with high water content. However, the phenomenon of “condensate sticking to the wall” may arise due to low temperatures in the cold region, which affects the safe production of this process. In this study, the safe production temperature limit of high water content crude oil in a cold climate without heating is determined by using a combination of a cold finger experiment and a field test. Research using cold finger devices indicates that crude oil’s viscous wall temperature typically below the pour point and diminishes as water content and shear stress rise. Through field tests with gradually decreasing oil–water mixture temperatures, the relationship between the oil–water mixture temperature and pipeline pressure drop is established. The temperature at the pressure drop surge point is then chosen as the limit for unheated gathering and transportation. A model for calculating the viscous wall temperature considering the flow state is established, its average calculation error is 1.44%. This study can provide important guidance for the feasibility judgment of the unheated gathering and transportation process and its safe operation in oil fields in cold regions.

Boosting solvent resistance and structure stability of degradable polyester through extended-chain crystal structure: A preliminary case of oil/water separation membrane

Developing polymer-based oil/water separation membranes has emerged as a promising approach for wastewater, and fabrication of environmental-friendly separation membranes is becoming a vital issue for sustainable development. Currently, the application of degradable polyesters for oil/water separation is severely limited due to their inferior resistance to various solvents. Herein, we report a new kind of separation membrane of degradable aliphatic polyester based on extended-chain crystals. Though significant improvements in the crystalline structure, including crystallinity and thermodynamic stability, the polyester membranes gain outstanding solvent resistance, maintaining their structural integrity even after prolonged immersion in diverse solvents for up to 100 days. Meanwhile, the hydrophobic and lipophilic characteristic of aliphatic polyester is well inherited in the separation membrane, imparting exceptional wettability to various solvents. Consequently, the extended-chain crystal porous membranes exhibit excellent flux performance and good separation efficiency for solvent and water mixtures and emulsions. In addition, the extended-chain crystal structure gives the membrane outstanding mechanical properties. This work provides the first membrane application report of extended-chain crystal in degradable aliphatic polyester and reveals the potential of extended-chain crystal materials to deliver superior performance and extensive application.

Altering the percolation threshold of PA66‐copper hybrid in an electroless copper deposition process by surface activation of the polymer

AbstractIn this study, the impact of three different principles of surface activation techniques for polyamide fibers on the formation of conductive percolation during the subsequent electroless copper deposition process was investigated. The techniques used are (1) polyamide complexation using a solution mixture of calcium chloride, ethanol and water, (2) atmospheric plasma surface treatment and (3) grafting of 2‐hydroxyethylmethacrylate by radical induced polymerization. As a result, the percolation threshold was shifted to lower copper contents. The copper content required to form conductive structures was reduced ranged between 59% and 89%, depending on the activation techniques. Furthermore, the deposition time was reduced by 37%–57%, resulting in a faster build‐up of the percolation on the fabric. Changes in wetting behavior and substrate surface topography were identified to be the main reasons for these observations. While all applied surface activation techniques led to higher copper contents compared to unmodified reference, the atmospheric plasma modification led to the highest copper contents during the deposition process and a more uniform appearance of the metallised layer.Highlights Three different fiber surface activation methods are evaluated. Fiber surface activation increases wetting and polymer‐metal adhesion. Activated polymer surface leads to faster copper deposition and percolation. Atmospheric plasma modification is the most efficient technique.

Effect of Epidermal Mucous Secretion of Earthworms and other Selected Organic Substances on Rooting of Semi-Hardwood Cuttings of <em>Citrus aurantifolia</em> and Top Cuttings of <em>Dracaena sanderiana</em>

A recent trend in plant growth and propagation is to use natural substances rather than synthetic plant growth regulators. Two experiments were conducted to find out the effect of epidermal mucous secretion (EMS) of earthworms and other organic substances including Aloe vera gel, coconut water and ripe banana on rooting of semi-hardwood cuttings of Citrus aurantifolia and top cuttings of Dracaena sanderiana compared to commercially available plant growth regulators (PGRs). Eleven treatments were prepared using sole application of EMS solution, Aloe vera gel, coconut water and ripe banana, and mixtures of EMS and other organic substances in two different ratios by allocating equal and more inputs from EMS. The present experiments were set up adopting a completely randomized design. The number of roots per cutting, total root length per cutting (cm), length of the longest root per cutting (cm) and root vigor score were recorded for both plant species where destructive sampling was done at two months after planting for C. aurantifolia and one and two months after planting for D. sanderiana. The number of roots per cutting, length of the longest root per cutting and the root vigor score were significantly greater in the control treatment that used commercially available PGR and the cuttings treated with EMS: coconut water (1:1) for C. aurantifolia suggesting the possibility to us EMS and coconut water mixture to substitute the PGR for root induction in C. aurantifolia. The number of roots, total root length and the length of the longest root per cutting were significantly high in the treatments administrated with Aloe vera gel, ripe banana, and a mixture of EMS: ripe bananas (1:1) together with the PGR at two months after planting for D. sanderiana. Hence, the ingredients listed above could be utilized as alternative organic substances to produce adventurous roots in D. sanderiana top cuttings as same as the PGR. The results of the present study could be extremely valuable for developing a unique organic rooting replacement for the synthetic root inducing materials for C. aurantifolia and D. sanderiana. Nonetheless, additional research is required to validate the results of this study.

Numerical simulation of submarine landslide tsunamis based on the smoothed particle hydrodynamics model

This paper establishes a SPH (Smoothed Particle Hydrodynamics) model for simulating underwater landslides based on the mixture theory. This model requires only one layer of particles, which greatly improves the computational efficiency compared with the traditional two-layer particle simulation for a mixture theory scheme. In the numerical model, based on a mixture theory, submerged landslide flow is regarded as a mixture of water and sediment phases and is discretized into a series of SPH mixed particles employing the volume fraction of the sediment phase. Using this volume fraction, a convection–diffusion term is calculated to represent the material transport between the water phase and the sediment phase. In addition, based on this volume fraction, the SPH mixed particles at any location in the considered domain are classified into three categories: (i) pure water, (ii) low-concentration suspended sediment, and (iii) high-concentration sediment. Pure water is treated as a Newtonian fluid. High-concentration sediment is modeled as a non-Newtonian fluid, and the Herschel–Bulkley–Papanastasiou rheological model is used to describe the viscous forces. The viscosity of the low-concentration suspended sediment, which acts as a transition layer between pure water and high-concentration sediment, is derived from the Chezy relation. A comparison of the numerical and experimental results demonstrates the high accuracy of the present numerical scheme. Using this validated numerical model, underwater landslides are simulated. Specifically, the effects of landslide deformation and compaction degree on the amplitudes of the surge wave crest and trough are investigated.

Ionic liquid interactions with cellulose and the effect of water

Ionic Liquids (ILs) have been used to address issues such as recyclability, cost-effectiveness, and tailored thermophysical properties. This is most relevant to recent efforts directed at dissolving cellulose for filament spinning and bioproduct development. Herein, we introduce a simple method to investigate how interactions between cellulose films (roughness, Rh = 37 nm) and ILs specifically 1-butyl-3-methylimidazolium acetate ([bmim][OAc]), 1-butyl-3-methylimidazolium chloride ([bmim][Cl]), 1-ethyl-3-methylimidazolium acetate ([emim][OAc]), and 1-ethyl-3-methylimidazolium chloride ([emim][Cl]), along with their water mixtures (0, 5, and 10 wt%) affect thermophysical properties relevant to cellulose dissolution (surface tension, γ; contact angle, θ; diffusivities, D; and bulk density, ρ) at 363.15 K and 0.1 MPa under argon and air atmospheres. Thermophysical properties relevant to cellulose dissolution were measured at 363.15 K and 0.1 MPa under argon (surface tension, γ, contact angle, θ), and air (diffusivities, D and bulk density, ρ) atmospheres to reveal the effect of the IL counter ions on the involved interactions with water. In general, water increased γ, θ, but reduced D, which supports experimental observations indicating the detrimental effect of water on IL-cellulose interactions. The [emim]+ cation (in [emim][OAc] and [emim][Cl]), produced a lower contact angle with cellulose while the interfacial properties (γ, θ, D) for ILs with the [OAc]− anion were marginally affected by water. By contrast, the two ILs carrying [Cl]− anions exhibited a significant reduction in D (from 11.7·10-13\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\cdot {10}^{-13}$$\\end{document} to 2.9·10-13m2s-1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\cdot {10}^{-13} {m}^{2}{s}^{-1}$$\\end{document}) in the cation shift from [emim]+ to [bmim]+ at 363.15 K and 0.1 MPa, with 0% water content. Overall, we present a methodical approach rooted in experimental and theoretical approaches to facilitate our understanding of ionic liquids (ILs), especially within the domain of bioprocessing.Graphical

Solvent-Mediated Synthesis and Characterization of Li3InCl6 Electrolytes for All-Solid-State Li-Ion Battery Applications.

Superionic halides have attracted widespread attention as solid electrolytes due to their excellent ionic conductivity, soft texture, and stability toward high-voltage electrode materials. Among them, Li3InCl6 has aroused interest since it can be easily synthesized in water or ethanol. However, investigations into the influence of solvents on both the crystal structure and properties remain unexplored. In this work, Li3InCl6 is synthesized by three different solvents: water, ethanol, and water-ethanol mixture, and the difference in properties has been studied. The results show that the product obtained by the ethanol solvent demonstrates the largest unit cell parameters with more vacancies, which tend to crystallize on the (131) plane and provide the 3D isotropic network migration for lithium-ions. Thus, it exhibits the highest ionic conductivity (1.06 mS cm-1) at room temperature and the lowest binding energy (0.272 eV). The assembled all-solid-state lithium metal batteries (ASSLMBs) employing Li3InCl6 electrolytes demonstrate a high initial discharge capacity of 153.9 mA h g-1 at 0.1 C (1 C = 170 mA h g-1) and the reversible capacity retention rate can reach 82.83% after 50 cycles. This work studies the difference in ionic conductivity between Li3InCl6 electrolytes synthesized by different solvents, which can provide a reference for the future synthesis of halide electrolytes and enable their practical application in halide-based ASSLMBs with a high energy density.

Synthesis and Characterization of New Azo Dye Derived from Sulfamethaxolevia Diazonium Reaction and Study its Abilityas an Acid-base Indicator

Background: Most azo dyes are synthesized by diazotization of a primary amine, followed by conjugation with one or more electron-rich nucleophiles. Objective: This study presents the synthesis of a new azocompound by converting sulfamethoxazole to a diazonium salt. Methods: via reaction with hydrochloric acid and sodium nitrite at temperatures between 0 and 5 °C, the resulting salt is then coupled with a 4-methoxyphenol reagent in alkaline medium at the above temperatures to produce an azodye given the IUPAC name of (4-((2-hydroxy-5-methoxyphenyl)diazenyl)-N-(5-methylisoxazol-3yl)benzenesulfonamide). The azo dye precipitate was purified by crystallization methods using a solvent mixture of ethanol water. Characterization was done using different analytical methods such as IR, UV-Vis and H1-NMR in addition to measurements of physical properties. Results: The reddish-pink azo compound gave a maximum absorbance of 495 nm. Acid-base titrimetric analysis was conducted to examine the chemical indicator properties of the azo dye. Clear color differences were obtained between two spaces in the pH range 2-12, where a reddishpink color was obtained in the basic medium and a yellow color in the acidic medium. Conclusions: A new azo dye successfully presented its properties as an indicator.

Development of a new reagent for the prevention of asphaltene-resin-paraffin deposits

Asphaltene-Resin-Paraffin deposits (ARPD) form a certain proportion of the crude oil mass, separating as temperature and pressure decrease and adsorbing to the surfaces of the reservoir wellbore zone, downhole equipment and tubulars. These deposits precipitate in the wellbore zone, oilfield equipment and pipes,resulting in reduced system productivity, reduced pumping efficiency of the pumping equipment and other negative consequences. Asphalt-resin and paraffin deposits (ARPD) are a complex mixture of solid paraffin hydrocarbons, asphalt-resin substances (ARS), water and mechanical impurities. The strength and composition of ARPD depend on the composition and properties of oil, geological, physical and technological conditions of field development. Chemical methods for removing deposits are currently the most widely used, as they are highly effective and technologically advanced. To this end, new reagents have been developed and their physico-chemical properties have been studied. Subsequently, the selected reagents were tested on oil samples from Oil and Gas Production Department (OGPD) with a paraffin content of more than 6 %. It was also shown that paraffin inhibitors have individual effects; a reagent that is effective on oil from one field may not have the same effect on oil from other fields. The research includes studies of selected reagents for paraffinic oils from different fields. Using the «cold finger» method, the efficacy of the selected reagents against paraffin deposition was investigated and their optimum doses were determined. Keywords: reagent; sendiment; paraffin; asphaltene; resin; well bottom zone; viscosity; depressor.