Magnesium Chloride Research Articles

An improved approach of salting-out solvent-free microwave mediated rotary distillation for essential oil preparation from fresh leaves of magnolia (Oyama sieboldii).

An improved method denoted as salting out-solvent-free microwave rotary distillation (SOSFMRD) was successfully developed for the extraction of essential oils from fresh magnolia (Oyama sieboldii) leaves, in which we achieved the rotation of the reaction material by means of a rotating motor to subject the material to uniform microwave irradiation. Magnesium chloride was selected as the salting-out agent through a comparative study on the salting-out effects of different anions and cations of metal salts. The variables of SOSFMRD were systematically optimized. Under the obtained optimization conditions, the essential oil yield was 21.68±1.02mL/kgDW. Gas chromatography-mass spectrometry analysis showed that the main chemical constituent of O. sieboldii essential oil was dehydrocostuslactone, the content of which reached 30.23±1.27%. Compared with the other conventional methods, this method has a high yield and low energy consumption, which can effectively reduce impact on the environment.

Total synthesis of (–)-negamycin from a chiral advanced epoxide

A concise route for the total synthesis of (–)-negamycin is described. Key point features (a) Cu-mediated ring-opening reaction of the advanced epoxide with vinyl magnesium chloride leads to the introduction of the carboxyl synthon; (b) Consecutive placement of diamino groups via azides was designed, including an unexpected cleavage of the silyl protecting group; (c) removal of four hydrogenolytically labile groups in one step.

Effect of a eutectic mixture of D-Mannitol and Magnesium Chloride Hexahydrate on reversible solar thermoelectric power generation: An experimental study

• The TEG rejected thermal energy is stored and reused for reverse power generation. • The thermophysical properties of different PCM compositions are analysed. • The electrical performance of TEG incorporating thermal storage is analysed. • The optimized thermal storage composition is 30% MgCl 2 .6H 2 O + 70% D-Mannitol. • The thermosyphon cooling is 4.11 times more effective than natural cooling at 90 W. An experimental analysis of the integration of Magnesium Chloride Hexahydrate mixed with D-Mannitol as the Phase Change Material (PCM) on the colder part of the Thermoelectric Generator (TEG) for day and night power production in solar applications was validated. The heat sink container was filled with different mixtures of PCM to store thermal energy in order to produce a continuous supply of power extended into the night. The experimental arrangement was set for cooling achieved using thermosyphon passive and natural convection. The voltage in open circuit and electrical power were tested for various mixtures and heat inputs while heating and for two types of cooling phases, namely, natural and thermosyphon cooling phases. A 70% D-Mannitol and 30% MgCl 2 .6H 2 O was observed to be the best concentration for all cases of compositions and heat inputs. When cooling using thermosyphon was employed for the TEG cooling system operating with the best concentration subjected to input heat values of 10, 30, 60 and 90 W, the maximum averages of the electrical power output of the TEG were increased to 0.24, 1.26, 1.83 and 1.89 W respectively, with every value being 4.19, 4.17, 4.05 and 4.11 counts greater than the respective measures obtained when cooled naturally.

A self-powered PVA-based flexible humidity sensor with humidity-related voltage output for multifunctional applications

In the context of the industry that supports green energy and electronics, the development of a humidity sensor with self-powered characteristics and the ability to be worn by humans is crucial for expanding its practical applications. Here, we report a self-powered flexible humidity sensor based on a sandwich structure of polyvinyl alcohol (PVA)/nanocarbon powder (NCP)/magnesium chloride (MgCl2) moisture-sensitive composite film (PCMF) and Cu and Al conductive adhesive tape. This unique sandwich structure allows it to readily adsorb and diffuse water molecules in humid environments, greatly enhancing its responsiveness to humidity changes. The Cu/PCMF/Al sensor generates voltage corresponding to different relative humidity (RH) levels and has a unique RH-Voltage linear response characteristic (R2 = 0.9978), notable for its fast response/recovery (6/11 s), wide detection range (RH 11%−98%), long-term stability (over 30 days), and high voltage (∼0.6 V) and current (∼2.3 µA) output at RH 98%. More importantly, due to the good water solubility of PVA and MgCl2 salts, the designed sensor exhibits recyclability and reusability properties (90.31% of the original response voltage value), which can significantly minimize material waste and potentially reduce manufacturing costs. In addition, this sensor can be successfully applied to domains involving human wearables, such as being integrated into a mask for monitoring human respiration, and has excellent identification capabilities even for simple coughs and pronunciations. The demonstration of non-contact humidity sensing validates the prospective application of this sensor in non-contact switching devices. This work presents a novel design idea for the development of wearable humidity sensors with low cost, simple preparation, and high responsiveness, as well as self-powered characteristics.

How Brine Composition Affects Fly Ash Reactions: The Influence of (Cat-, An-)ion Type

Abstract Hypersaline brines can be solidified and stabilized via the hydraulic and pozzolanic reactions between fly ash(es) and calcium-based additives. Although recent work has examined fly ash reactivity in single-salt (“simple”) hypersaline brines (ionic strength, Im > 1 mol/L), the effects of mixed-salt solutions on fly ash reactivity remain unclear. Herein, the reactivity of a Class C (calcium oxide [CaO]-rich) or Class F (CaO-poor) fly ash mixture with calcium hydroxide is reacted in solutions bearing sodium chloride (NaCl), calcium chloride (CaCl2), magnesium chloride (MgCl2), sodium sulfate (Na2SO4), or combinations thereof for 1.5 ≤ Im ≤ 2.25 mol/L, from 1 week until 24 weeks. Expectedly, sulfate anions promote the formation of sulfate phases (i.e., ettringite, monosulfoaluminate, U-phase), while chloride anions induce the formation of Cl-AFm compounds (i.e., Kuzel’s and Friedel’s salt). Although the Class C fly ash’s reactivity is similar across different anions (for a fixed cation and Im), Class F fly ash shows a small change in reactivity depending on the anion present. NaCl suppresses (Class C and Class F) fly ash reactivity by up to 30 % as compared to neat CaCl2 and MgCl2-based brines. Thermodynamic modeling reveals that NaCl induces a considerable increase in pH—up to 13.7, where many hydrated phases of interest cease to be the major phase expected—as compared to CaCl2 and MgCl2 brines (pH < 13). In mixed-salt brines, anion immobilization is competitive: sulfate achieves a greater level of incorporation into the hydrates, as compared to chloride. These results offer new understanding of how the brine composition affects solidification and stabilization and thereby yield new insight into improved approaches for wastewater disposal.

Influence of Modified Ziegler–Natta Catalyst on the Entanglement Behavior and Properties of Ultrahigh-Molecular-Weight Polyethylene (UHMWPE)

Different dealcoholizing methods and polyhedral oligomeric silsesquioxanes (POSS) were utilized for the modification of Ziegler–Natta catalysts. Their effects on the properties of the catalysts and the synthesized ultrahigh-molecular-weight polyethylene (UHMWPE) were thoroughly studied. It was found that physical dealcoholization of the magnesium chloride–ethanol adducts increased the specific surface area (SSA) of the catalysts more effectively than chemical dealcoholization, expanding the contact area between active centers and ethylene. Thus, better catalytic activity was induced. The sufficient distance between growing chains is the key point in the entanglement degree of UHMWPE. With the load of TiCl4, physical dealcoholized catalysts always provide greater spacing between growing chains, decreasing the potential of segment tangling, and that matches the less-entangled state of the synthesized UHMWPE determined by the initial storage modulus by a rotary rheometer. The modification of the catalysts by polyhedral oligomeric silsesquioxanes (POSS) was also studied, and it was discovered that POSS shows little effect on catalytic activity. However, POSS-modified catalysts limited the active centers to a closer range. Coupled with the strong interaction between UHMWPE and POSS particles, UHMWPE with a higher entanglement state were produced. The crystallization behavior and mechanical properties of the obtained UHMWPE were also studied.

Viability of waste heat capture, storage, and transportation for decentralized flowback and produced water treatment

The use of waste heat has been proposed to reduce the energy footprint of membrane distillation for flowback and produced water (FPW) treatment. However, its feasibility has not been fully understood for FPW treatment. Accordingly, this study performs systematic assessments through thermodynamic modelling of waste heat capture, storage, and transportation for decentralized FPW treatment at well pads located in the Denver-Julesburg Basin. A wide range of sensible, phase-change, and thermo-chemical storage materials were assessed for their effectiveness at the utilization of waste heat from on-site hydraulic fracturing engines and natural gas compressor stations, in order to overcome the temporal or spatial mismatch between waste heat availability and FPW generation. Our results show that the type of storage material being used can have a high impact on the efficiency of waste heat utilization and the treatment capacity of membrane distillation. Sensible storage materials only utilize sensible heat capacities, while phase-change materials have improved performance because they are able to additionally store latent heat. However, sensible and phase-change storage materials lose 11–83% of heat due to conversion inefficiencies caused by their changing temperatures. Thermo-chemical materials, on the other hand, have the highest potential for use because they collect and release heat at constant temperatures. We identified three thermo-chemical storage materials (magnesium sulfate, magnesium chloride, and calcium sulfate) with the best efficiencies due to their elevated discharge temperatures which reduce the energy consumption of membrane distillation. In addition, these materials have high volumetric energy storage density, which enables capture and transportation of waste heat from remote locations such as natural gas compressor stations to the well sites, yielding up to 70% reduction in transportation costs relative to moving FPW to centralized treatment facilities at natural gas compressor stations. Our study, for the first time, demonstrates the importance of selecting appropriate energy storage material for leveraging low-grade thermal energy such as waste heat to power membrane distillation for decentralized wastewater treatment.

Methyl cellulose-based solid polymer electrolytes with dispersed zinc oxide nanoparticles: A promising candidate for battery applications

Novel solid polymer electrolytes based on methyl cellulose (MC) and magnesium chloride (MgCl₂⋅6H₂O) have been prepared by a solution casting technique. The best conducting polymer electrolyte system has been doped with different amounts of zinc oxide (ZnO) nanoparticles to assess their effect on its properties. Structural studies by FTIR and XRD analysis have revealed complete complexation between the polymer host and the dopant. A polymer electrolyte system with 25 wt% of the salt exhibited the highest room temperature ion conductivity of 1.18 × 10⁻⁴ S cm⁻1 with excellent thermal and dielectric properties. The dispersal of ZnO nanoparticles therein served to enhance the conductivity. SEM micrographs reveal complete dispersion of the nanofiller on the electrolyte surface. A primary battery has been fabricated, and its open-circuit potential and discharge characteristics have been studied. Overall, the prepared electrolytes have excellent properties and may thus be promising candidates for energy storage devices.

Electrochemical promoted C[sbnd]H bond chlorination of sulfoxonium ylides

The first electrochemical promoted CH bond chlorination of sulfoxonium ylides was accomplished using magnesium chloride as the chlorine source, as well as a supporting electrolyte. This method does not require transition metal catalysts, external oxidants, and electrolytes, providing a green and mild route for the functionalization of sulfoxonium ylides.

Characteristics and Mechanisms of Phosphorous Adsorption by Peanut Shell-Derived Biochar Modified with Magnesium Chloride by Ultrasonic-Assisted Impregnation.

Recovery of phosphate (P) from sludge, domestic wastewater, and industrial wastewater is beneficial for overcoming the problem of shortage of P rock resources. In this study, Mg-functionalized peanut shell-derived biochar was prepared by ultrasound-assisted impregnation. The obtained Mg-laden biochar had a higher content of Mg, a larger specific surface area, and more porosity. The prepared Mg-modified biochar exhibited excellent adsorption properties of phosphorus. Modified biochar has a higher amount of adsorbed P than raw biochar. The capacity of P adsorption by modified biochar was 30.48-114.24% higher than that by raw biochar. Moreover, the Mg-laden biochar can be applied in a wide working environment (pH: 2-10; temperature range: 15-40 °C). This study not only develops a new strategy for the preparation of high-capacity P adsorbents but also provides a new green use for agricultural peanut shells.

Beneficial effects of adding magnesium to desalinated drinking water on metabolic and insulin resistance parameters among patients with type 2 diabetes mellitus: a randomized controlled clinical trial

There is evidence that increasing the consumption of water containing magnesium can improve glucose metabolism and insulin resistance in patients with type 2 diabetes mellitus (T2DM). This trial was undertaken with the objective of evaluating the effect of adding different concentrations of magnesium chloride to the desalinated drinking water on the glycemic, metabolic, and insulin resistance parameters among patients with T2DM. A randomized cross-sectional controlled clinical trial was conducted to evaluate the effects of adding magnesium chloride supplement to desalinated drinking water consumed by patients with T2DM on the glycemic and metabolic parameters and indicators of insulin sensitivity. The total number of patients with T2DM who successfully completed the trial is 102. Patients were randomly allocated into three groups: the first group received bottled water without added magnesium (0 mg/L) (Group A, n = 37); the second group received bottled water with a low level of magnesium (20 mg/L) (Group B, n = 33); and the third group received drinking water with a high level of magnesium (50 mg/L) (Group C, n = 32). The daily consumption of elemental magnesium for a period of 3 months resulted in significant improvement in HbA1C (8.0 vs 8.2%, p = 0.04), insulin level (7.5 vs 9.9 μIU/mL, p = 0.03), and homeostasis model assessment-estimated insulin resistance (HOMA.IR) (2.5 vs 2.9, p = 0.002) in group C. However, there was no significant improvement in fasting blood glucose (FBS) level or lipid profile. The results of this study suggest that oral magnesium supplementation at the given dose of 50 mg/L daily added to drinking water could improve long-term glycemic control indicators and reduce insulin resistance in patients with T2DM.

Water reclamation from anodizing wastewaters by removing reactive silica with adsorption and precipitation methods

Water stress is a current environmental menace mainly driven by over exploitation of aquifers, which is triggering poor water quality with high concentration of minerals in extracted groundwater. Particularly, silica is widespread in natural water supplies due to weathering processes of silicates occurring in contact with water, light, air, and other factors. However, due to groundwater over extraction the concentration of silica has increased during the last years in aquifer reservoirs from Aguascalientes State (México). In this context, it is very important to note that the removal of silica compounds from water is challenging and different methods can be used to avoid embedding problems in different industries. In the present work, the removal of reactive silica from synthetic solutions as well as from real wastewaters from an industrial anodizing process was studied using adsorption and chemical precipitation methods. Twelve commercial materials of different nature were used for adsorption tests, while seven precipitant agents were applied in the precipitation experiments. Adsorption tests were performed in batch systems with constant stirring at 30 °C and at different pH values (7 and 9). Precipitation experiments were carried out in batch systems and the best conditions for silica removal were found using an L9 orthogonal array of the Taguchi method employing molar ratio, pH of wastewater, stirring time and temperature as experimental factors.Adsorption results showed that Ferrolox (Iron (III) hydroxide-base adsorbent) was the most efficient sorbent for reactive silica removal from synthetic solutions and the anodizing wastewater. Also, the reactive silica adsorption was higher at pH 9 as compared to that measured at pH 7 and the adsorbed quantity at pH 9 was 16.22 and 11.25 mg/g for the synthetic solution and anodizing wastewater, respectively. According to molecular simulation, the main interaction between Ferrolox and silica species was related to the formation of hydroxo-complexes and to the interaction of Fe with oxygen of silica species. Additionally, magnesium chloride was the best precipitating reagent for reactive silica achieving up to 87% removal. According to ANOVA analysis of Taguchi method, pH was the most influential factor during the precipitation of reactive silica with a variance value of 81.42, while values lower than 3 were obtained for the rest of parameters. Overall, the present work is reporting for the first time the removal of reactive silica from anodizing wastewaters with promising results that can be implemented at full scale for water reclamation, which may significantly contribute to manage water reservoir in the region sustainably.

An Investigation Into Local Infusion Site Pain After Infusion of Ultra Rapid Lispro Excipients Across Sites and Depths.

This phase 1, randomized, one-day, five-period crossover study in adults with type 1 diabetes on continuous subcutaneous insulin infusion investigated local infusion site pain following infusion of the excipients of ultra rapid lispro (URLi; without insulin) across infusion sites and depths. Forty participants (mean age, 40.5 years; body mass index [BMI], 27.5) were randomized to one of five infusion site sequences consisting of the arm, thigh, buttock (6 mm cannula depth), and abdomen (6 and 9 mm depth). Basal infusion of sodium citrate and treprostinil in diluent with magnesium chloride was initiated (10 μL/h) and at three, six, and nine hours after basal initiation, 15 unit-equivalent boluses (150 μL) were given. Participants rated their pain on a 0 to 100 mm validated visual analog scale (VAS) at 5 minutes pre-bolus and 1 and 15 minutes post-bolus. At one minute post-bolus, increased VAS scores were occasionally reported. Most one minute post-bolus scores were ≤10 mm (little to no discomfort) while 7 of 577 were >45 mm (generally considered clinically meaningful pain). Painful infusions were reported more frequently for the arm, and mean VAS scores were higher for the arm compared with the thigh and abdomen. The VAS score distributions were similar between cannula depths. By 15 minutes post-bolus, VAS scores returned to pre-bolus levels. Local infusion site discomfort after infusion of URLi excipients was reported by a small subset of participants; it was transient, tolerable, and dependent on infusion site but not infusion depth. Given differences within individuals, patients may consider using a different infusion site if they experience discomfort. NCT05067270.

Synthesis and mechanism of a new environment-friendly flame retardant (anhydrous magnesium carbonate) by hydrothermal method

In this study, the synthesis and formation mechanism of anhydrous magnesium carbonate (AMC) using hydrothermal method is proposed from the perspective of ionic reaction. Validation experiments were conducted, and the effect of the pH of the reaction solution and the form of carbon source on AMC preparation was investigated. It is found that HCO3− can accelerate crystal growth and reduce crystal size, and the preparation conditions of AMC can be quantified. The AMC particles were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The AMC prepared using urea as carbon source has a small particle size in the presence of ion pairs of Na+/Cl− or K+/SO42−. AMC prepared using magnesium chloride as magnesium source has smaller composition units than those prepared using magnesium sulfate as magnesium source. The effects of ions types, reaction temperature, reaction time and filling degree on the phase transition and crystal growth of AMC are also discussed.

Effect of marble slurry as filler on soundness and compressive strength of magnesia cement

Investigation, the effect of different amounts of marble slurry as filler on soundness and compressive strengthof magnesia cement has been carried out in this paper. For this purpose, three different dry mix compositions(1:0; 1:1 and 1:2) of magnesia and marble slurry were prepared. The dry mixes were then gauged with30°Be concentration of magnesium chloride gauging solution. It was observed soundness as well ascompressive strength decrease with increasing amount of marble slurry in dry mix composition.

Chemical Analysis of Groundwater and Wastewater in the Area of the Tengiz Deposit of the Atyrau Region of the Republic of Kazakhstan

This article analyzes the content of the chemical composition of groundwater and wastewater of the Tengiz deposit located in the Zhyloy district of Atyrau region of the Republic of Kazakhstan. This analysis is necessary to determine the deposition of inorganic salts in oilfield equipment. The analysis shows that the content of chloride anions and magnesium cations prevails in groundwater and wastewater. Thus, the content of chloride anions exceeds the content of other anions up to 2-3 times of sulfate anions in groundwater and wastewater and up to 2.5-5 times of bicarbonate anions in groundwater and 17-27 times in wastewater. Among the cations, the maximum values are characteristic of magnesium cations, whose content exceeds the calcium content by more than 3.5 times in wastewater and more than 6.5 times in groundwater. In addition, the magnesium content exceeds more than 5 times the content of the sum of sodium and potassium ions. Thus, according to the results of the study, it was determined that the main salts affecting the oilfield equipment at the Tengiz field are magnesium chloride salts.

Homogeneous precipitation of Mg/Al layered double hydroxide from concentrated metal salt solution under hydrothermal conditions

Homogeneous precipitation using urea hydrolysis under hydrothermal conditions has been examined to prepare carbonate type magnesium aluminium layered double hydroxides (Mg/Al-CO3 LDHs). To obtain well-crystallized Mg/Al-CO3 LDHs as single phase, low concentration starting solutions have been used, resulting in the small amount of product from a batch. In this study, concentrated starting solution of magnesium chloride and aluminum chloride (total metal salts concentration of 1.0 ​M) was used to achieve bulk syntheses. The reaction conditions were optimized to obtain well-crystallized Mg/Al-CO3 LDH of rosette-like shape with the radius of ca. 2–4 ​μm in a large scale (7.6 ​g from 160 ​mL container). The parameters including heating rate and reaction temperature were found to be important to avoid the formation of by-products, and the Mg/Al ratio in the initial solution influenced the composition and morphology of the products. The heating rate of 8 ​°C/min and the reaction temperature at 100oC successfully led to single-phase Mg/Al LDHs.

Synthesis, growth and characterization of magnesium chloride doped L-alanine cadmium chloride single crystal: For nonlinear optical application

The aim of this research was to synthesize and characterize pure and magnesium chloride (MgCl2) doped L–alanine cadmium chloride (LACC) single crystals. Pure and MgCl2 doped LACC single crystals were synthesized by solution method with slow evaporation solution growth technique at room temperature. The single crystal X-ray diffraction studies of pure, 1 and 2 mol% MgCl2 doped LACC single crystals revealed monoclinic crystal structure with C2 space group. The optical properties of pure and MgCl2 doped LACC single crystals investigated by UV–VIS/NIR spectrometer confirmed that the crystals were transparent in the wavelength range of 230-1100 nm. The optical band gap energy of pure and doped LACC single crystals were found to have the same value of 5.4 eV. The energy-dispersive X-ray analysis indicated the incorporation of magnesium and chlorine atoms in LACC single crystal. The second harmonic generation efficiency of 1 and 2 mol% MgCl2 doped LACC crystals were analyzed by Kurtz-Perry powder technique and found to be 1.75 and 2 times greater than that of the standard potassium dihydrogen phosphate crystal, respectively.

A Physicochemical Study of Cost-Effective Liquid Desiccants for Use in an air conditioning systems

Liquid desiccant systems (LDS) have attracted attention as promising low-energy alternative cooling solutions relative to conventional systems. An integral part of the LDS dehumidification capability depends on the composition of the hygroscopic desiccants utilized. The vapour pressure of different hygroscopic salt solutions and mixtures thereof have been measured at a temperature of 298.15K using a Yamamoto configuration. The initial validation of the measurement configuration using a single salt solution has exhibited a satisfactory correlation with vapour pressures reported by previous authors at various concentrations. The performance of MgCl2 solution was found to be comparable to that of LiCl. The results have shown that MgCl2 solution with 30% w/v concentration is sufficient to maintain the equilibrium relative humidity (ERH) at 50%, the recommended value for the human comfort zone, a value close to that obtained from LiCl solution (ERH = 55%) with the same concentration. Moreover, the best performing salt solution mixtures were found to be magnesium and lithium chlorides. Considering that the cost of LiCl is 23 times higher than that of MgCl2, the potential replacement of LiCl with MgCl2 in LDS is very promising from both a performance and cost point of view. The concentrated seawater brines have also shown a very promising performance comparable with that of 50% CaCl2– 50% MgCl2 artificial mixture.

Magnesium chloride-modified potassium humate-based carbon material for efficient removal of phosphate from water

BackgroundTo solve the problem of eutrophication caused by phosphate, a metal-loaded biocarbon composite material is considered to be an effective adsorbent for removing phosphate. MethodsIn this study, potassium humate was used to prepare modified potassium humate-based carbon material (MPHCM) through magnesium chloride modification and rapid pyrolysis. Significant findingsStudies have shown that MPHCM can effectively remove phosphate from water. At 318 K and with pH=3, the maximum adsorption capacity reached 181.96 mg P g−1, and the adsorption process conformed to the pseudo-first and pseudo-secondary adsorption kinetic models and the Langmuir adsorption model. This adsorption process involved physical and chemical adsorption, which indicated monolayer adsorption. The main adsorption mechanisms for MPHCM were protonation, electrostatic interactions, ligand exchange and inner sphere complex precipitation. Six desorption cycles verified the excellent reproducibility of MPHCM for phosphate removal. Therefore, this study provides a new adsorbent for phosphate removal and expands the application range of potassium humate-based carbon materials.