Hydrochloric Research Articles

A novel trialkyl phosphate – Ionic liquid mixture for an efficient separation of Lithium ion from its acidic feed solution

Separation of Lithium ion (Li+) using conventional non-crown type ligands through solvent extraction process is a challenging task and can only be feasible by tuning the organic phase with an additional polar environment. In this context, we have projected an extracting system containing a traditional trialkyl phosphate (T(alk)P): Tri-iso-amyl phosphate (TiAP) containing a minimal amount of ionic liquid (IL): [C4mpip][NTf2] (1-butyl-1-methylpiperidinium bis(trifluoromethanesulfonyl)imide) for the efficient extraction and separation of Li+ from its hydrochloric acid feed. The extraction performances pertaining various experimental parameters were realized to explore the solvent potentiality of TiAP/[C4mpip][NTf2] towards Li+ coordination. Involvement of two ligand molecules in extraction in presence of 10 % (v/v) IL diluent offers fast extraction kinetics and turns the extraction mechanism into a cation exchange pathway, which was further examined by using different classes of ILs in conjunction with TiAP for Li+ uptake. The selectivity of Li+ over other alkali (or alkaline earth) metal ions was investigated to highlight the affinity of the proposed IL system towards Li+. Extraction scenario in TiAP phase was compared with that in TBP phase containing same IL to bring out the efficacy of the proposed IL system. The stripping performance of Li+ from the loaded organic phase was studied using an acid solution to establish the sustainability of the proposed extraction process.

Synergistic inhibition effect of diolefinic dye and silver nanoparticles for carbon steel corrosion in hydrochloric acid solution

The current work looks at the inhibitory effects of a diolefinic dye, namely 1,4-bis((E)-2-(3-methyl-2,3-dihydrobenzo[d]thiazol-2-yl) vinyl) benzene iodide salt, in relation to CS corrosion mitigation in hydrochloric acid (HCl) environment. This study uses a variety of experimental methodologies, including weight loss (WL) analysis, electrochemical tests, and theoretical considerations. The synergistic effect of diolefinic dye and AgNPs on the corrosion inhibition of CS in 1 M HCl was investigated. The inhibition efficiency (IE) displays a notable enhancement as the concentration of the dye is elevated and as the temperature raises the IE increases. The diolefinic dye exhibited % IE of 83% even at low concentration (1 × 10–4 M) whereas 90% in the presence of (2.26 × 10–10) AgNPs. Tafel graphs demonstrate that the dye follows a mixed type inhibitor. The adsorption of the dye on CS surface follows Langmuir model. Moreover, the influence of temperature and the activation parameters disclose that diolefinic dye is chemisorbed on the CS surface. The synergistic coefficient of the diolefinic dye and AgNPs under various concentration conditions was greater than unity. The surface morphology of CS sheets was confirmed by scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). Density Functional Theory (DFT) calculations provide theoretical support for the inhibitory effects of the examined dye. Notably, there is a high agreement between the findings of practical studies and theoretical expectations.

Spray dried protein concentrates from white button and oyster mushrooms produced by ultrasound-assisted alkaline extraction and isoelectric precipitation.

In the present study, the optimization of ultrasound-assisted alkaline extraction (UAAE) and isoelectric precipitation (IEP) was applied to white button (WBM) and oyster (OYM) mushroom flours to produce functional spray dried mushroom protein concentrates. Solid-to-liquid ratio (5-15% w/v), ultrasound power (0-900 W) and type of acid [HCl or acetic acid (AcOH)] were evaluated for their effect on the extraction and protein yields from mushroom flours submitted to UAAE-IEP protein extraction. Prioritized conditions with maximized protein yield (5% w/v, 900 W, AcOH, for WBM; 5% w/v, 900 W, HCl for OYM) were used to produce spray dried protein concentrates from white button (WBM-PC) and oyster (OYM-PC) mushrooms with high solids recovery (62.3-65.8%). WBM-PC and OYM-PC had high protein content (5.19-5.81 g kg-1), in addition to remarkable foaming capacity (82.5-235.0%) and foam stability (7.0-162.5%), as well as antioxidant phenolics. Highly pH-dependent behavior was observed for solubility (> 90%, at pH 10) and emulsifying properties (emulsification activity index: > 50 m2 g-1, emulsion stability index: > 65%, at pH 10). UAAE-IEP followed by spray drying increased surface hydrophobicity and free sulfhydryl groups by up to 196.5% and 117.5%, respectively, which improved oil holding capacity (359.9-421.0%) and least gelation concentration (6.0-8.0%) of spray dried mushroom protein concentrates. Overall, the present study showed that optimized UAAE-IEP coupled with spray drying is an efficient strategy to produce novel mushroom protein concentrates with enhanced functional attributes for multiple food applications. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Methylene Blue Solid Alginate Gels for Photodynamic Therapy: The Peculiarities of Production and Controlled Release of the Dye

The purpose of this work is to establish the influence of the nature of solid alginate gels (alginic acid, AAG; calcium alginate, CAG) and the conditions of methylene blue (MB) introduction to alginate matrices upon its release into aqueous media. MB is an active photosensitizer, which is used in the photodynamic therapy of tumors and purulent wounds. Solid alginate gels based on AAG and CAG were obtained by adding hydrochloric acid and calcium chloride to sodium alginate. The dye was introduced into the matrix either at the stage of gelation or by immersing the gel in an aqueous solution of the dye. It has been shown that the strength of the dye’s attachment to AAG is higher than that of CAG, which leads to a higher rate of MB release from CAG into aqueous media. It has also been shown that, when introduced at the stage of gel formation, MB is released into both the water and buffer solutions. When MB is introduced by gel immersion into an MB solution, the dye may be released only into salt solutions. An alginate gel with immobilized MB can be used as a solid photosensitizing system with the controlled release of the photoactive agent into the wound cavity for photodynamic treatment.

Acidity and Phase Behavior of Frozen Hydrochloric Acid during Thawing

Acidity and Phase Behavior of Frozen Hydrochloric Acid during Thawing

Polyhydroxybutyrate production from non-recyclable fiber rejects and acid whey as mixed substrate by recombinant Escherichia coli

Producing polyhydroxybutyrate (PHB) from agro-food processing waste has the potential to mitigate the global synthetic plastic pollution crisis and reduce greenhouse gas emissions. Additionally, it offers a promising solution to the challenges associated with high feedstock and production costs. This study aims to explore the use of two such wastes, non-recyclable fiber rejects (FR) (solid waste) and acid whey (AW) (liquid waste), as cost-effective and sustainable carbon sources for PHB production. Fiber rejects contains up to 50% carbohydrates that can be hydrolyzed to fermentable sugars. The AW is composed of lactose, lactic acid, fats, proteins, and mineral salts which could be used as carbon sources for PHB. The focus of this work was a comprehensive evaluation of substrate utilization, cell growth, and PHB inclusion in recombinant E. coli during the fermentation of various blends of acid whey and hydrolysate obtained from fiber rejects. Two approaches were investigated: i) produce FR hydrolysate and mix it with AW in various ratios (1:2, 1:1, and 2:1), and ii) use acid whey to replace water during the hydrolysis of FR. Combining acid whey with the hydrolysate achieved the highest PHB yield in a shorter duration compared to using only the hydrolysate. Replacing acid whey with water during the enzymatic hydrolysis of pretreated fiber rejects and utilizing it further for fermentation resulted in the highest PHB yield of 5.2 g/L, with a 45.4% PHB inclusion rate. Additionally, the inherent lactic acid content in acid whey eliminates the need for adding acetic acid to adjust pH levels during hydrolysis, thereby saving freshwater and acid.Graphical

Enhance the Performance of CZTSSe Solar Cells Through Inhibiting the Cu2+, Tu, and (─COOH) Association Reaction.

The Sol-gel precursor solution reaction mechanism has a significant impact on the Cu2ZnSn(S, Se)4 (CZTSSe) solar cells. It is discovered that in the Cu2ZnSnS4 (CZTS) precursor solution (CZTS-PS) in the preparation, there is an association reaction among Cu2+, thiourea (Tu), and carboxyl (-COOH), which is an important reason for the undesirable CZTSSe solar cells. The strong association reaction generates excessive Cu2+ ions, forming the CuxSe secondary phase on the surface of the CZTSSe absorber. The secondary phase causes a short circuit and deterioration of gadget performance. Following a 6-h aging period for the CZTS-PS, the average photoelectric conversion efficiency (PCE) of the device is enhanced to 8.02%, and there is also an improvement in device uniformity, as evidenced by a decrease in the standard deviation to less than 1. To inhibit the association reaction and eliminate the aging time phenomenon, a strategy is developed using hydrochloric acid to regulate the CZTS-PS environment. This strategy shifts the REDOX reaction in Cu2++Sn2+ toward the formation of Cu1++Sn4+, leading to a decrease in the defect concentrations of VSn(-/0) and CuSn(-/0), which increases the carrier concentration and reduces the impact of band tailing. The average power conversion efficiency (PCE) of the devices improved from 7.45% to 9.26%, the PCE of the best-performing CZTSSe solar cells increased from 9.25% to 9.83%, and the consistency among the devices is further enhanced, as indicated by a reduction in the standard deviation from 0.98 to 0.44. Ultimately, the device performance of the Cu2++Sn2+-DMF system improved by 11.01% (without the MgF2 layer) after optimization. This study serves as a reference for regulating the environment of the CZTS-PS to further enhance the CZTSSe devices' performance, and the photoelectric conversion efficiency is improved by ≈30%.

Experimental and theoretical simulations to examine the influence of nonionic surfactant on the corrosion control of mild steel in hydrochloric acid

The increasing demand for corrosion prevention strategies that are both effective and sustainable is part of the research the background. Nonionic surfactants offer a potential replacement for traditional corrosion inhibitors. These surfactants are well-known for their low toxicity and biodegradability. The research involved conducting experimental tests (such as weight loss, polarization and impedance spectroscopy) and theoretical computations to investigate the role of nonionic surfactant (polyoxyethylene (7) tribenzyl phenyl ether) (PETPE) in controlling the corrosion of mild steel in hydrochloric acid (1.0 M HCl) environment. The results of the study demonstrated that PETPE exhibited significant corrosion inhibition properties for mild steel in HCl solution. The inhibition efficiency of PETPE was found to increase with increasing PETPE concentration. PETPE is an excellent corrosion inhibitor because it significantly reduces the rate of corrosion, as seen by the notable inhibition efficiency result (95.4%) at a relatively low dose of PETPE (100 ppm). Thermodynamic studies were used to discuss the fundamental mechanisms that control PETPE-acid interactions. The adsorption process followed Langmuir adsorption isotherm, indicating a monolayer adsorption of the PETPE on the mild surface. Theoretical computations confirm the strong inhibition behavior of PETPE. The innovative feature of this research is its comprehensive strategy, which integrates experimental studies and theoretical simulations to evaluate the impact of PETPE on the corrosion control of mild steel in hydrochloric acid. The combined effort has the ability to supply valuable knowledge into the mechanisms of corrosion that will lead to the establishment of powerful corrosion control strategies.

Gelling ability and gel structure of soy protein isolate influenced by heating in the presence of various acids

This study investigated the influence of acids on gelation of soy protein isolate (SPI) under heating. Specifically, the SPI solution was acidified to pH 2.5 using hydrochloric acid (HA), acetic acid (AA), tartaric acid (TA) and citric acid (CA), respectively, and then heated at 85 °C. It was found that the SPI gel with the anisotropic structure was formed, which suggested that the gel resulted from the organized arrangement of the SPI fibril. Subsequently, it was confirmed by several techniques such as atomic force microscopy that the above acidic-thermal treatment induced fibrillation of SPI. Furthermore, the ability of these acids to promote gelation and fibrillation of SPI was in the order of CA > TA > HA > AA. In summary, these results suggested that heating at pH 2.5 resulted in SPI fibrillation, thus promoting SPI gelation, and the acidity regulator type had a profound effect.

Innovative Recycling and Conversion of Aluminum Waste to Hydrogen and Aluminum Chloride: Enhancing Economic Feasibility and Sustainability in Saudi Arabia

The rapid industrialization and urbanization in Saudi Arabia have led to significant challenges in waste management, particularly in recycling aluminum waste. This study explores an innovative approach for converting aluminum waste, specifically beverage cans, into valuable products such as aluminum chloride (AlCl3) and hydrogen (H2). The process involves the chemical reaction of aluminum with hydrochloric acid (HCl), producing AlCl3 and H2, and is modeled using Aspen Plus software. Two scenarios are evaluated: one without recycling and one incorporating recycling processes. In the first scenario, the direct conversion process yields 355 tons of AlCl3 and 9 tons of H2 per day from 100 metric tons of aluminum waste. The minimum selling price (MSP) of AlCl3 is calculated to be $764 per ton, with an annual profit of $25 million, assuming a market price of $1000 per ton. However, the economic viability of this scenario is highly sensitive to conversion efficiencies and market conditions. The second scenario integrates a recycling loop, processing 90% of the aluminum waste back into aluminum, significantly enhancing economic stability. This scenario produces 35 tons of AlCl3 and 1 ton of H2 per day, with an MSP of $1068 per ton. Despite the higher MSP, the inclusion of recycled aluminum, sold at $2400 per ton, results in a higher annual profit of $38 million, demonstrating greater economic resilience and sustainability. This study provides a comprehensive techno-economic analysis, highlighting the dual benefits of waste reduction and resource recovery. By optimizing reaction conditions and incorporating recycling, the proposed process aligns with Saudi Arabia's Vision 2030 sustainability goals, offering a viable pathway for enhancing economic feasibility and environmental sustainability in aluminum waste management.

PCR-free and visual detection of antibiotic resistance gene in feces genome of aquatic products by coupling CuO nanoparticles concatemers-Au@Fe3O4 and 3D DNA walker based on a portable blue light gel imager

Antibiotic resistance genes (ARGs) present a significant health issue, and the sensitive detection of ARGs is essential for preventing antibiotic resistance. Herein, a novel highly sensitive and visual biosensor was developed by combining gold nanoparticle (AuNP)-coated Fe3O4 (Au@Fe3O4), CuO nanoparticles (CuONPs) concatemers, Cu2+-triggered 3D DNA walker (DW, which included DNAzyme-capped AuNPs (DNAzyme@AuNPs) and AuNPs capped by substrate DNA modified with fluorescein (FAM-Sub@AuNPs), namely CuONPs-Au@Fe3O4-DW method. When the target ARG was present in the sample, it acted as a bridge between the complementary strand DNA (cDNA) on the surface of Au@Fe3O4 and H1-CuONP which paired with repeatedly H2-CuONP by a hybridization chain reaction, resulting in an ARG coupling multiple CuONPs (CuONPs concatemers) effects. After magnetic separation, hydrochloric acid was added to dissolve the CuONPs concatemers to release plenty of Cu2+ ions, which activated the DNAzyme@AuNPs of the DW. Subsequently, the FAM-Sub@AuNP of the DW was sheared by its DNAzyme, resulting that the FAM molecules kept away from AuNPs, and generated high fluorescence signals. The fluorescence signals can be measured by a 96-well microplate reader with a limit of detection (LOD) of 0.89 pM and visualized using a portable blue light gel imager with a LOD of 8.1 pM. Remarkably, the results of the qPCR method are high consistent with those of the microplate reader (r = −0.935) and the blue light gel imager (r = −0.994) in detecting tetA of aquatic faecal samples. Furthermore, our PCR free, high sensitivity and visual method is also suitable for the identification of other ARGs by replacing the corresponding gene sequence, and enables on-site detection of the ARGs in aquatic products by integrating the blue light gel imager.

A combined experimental and theoretical study into the effect of new heterocyclic compound containing β-lactam ring as corrosion inhibitor for mild steel in hydrochloric acid

In this study, a new corrosion inhibitor termed 2-(3-chloro-2-(4-hydroxy-3, 5-dimethoxyphenyl)-4-oxoazetidin-1-yl)-1-methyl-1H-imidazole-4(5H)-one (COMI) has been synthesized, diagnosed, and tested as a potential candidate for mild steel corrosion prevention in 1M HCl. The research combined experimental and theoretical approaches. Experimentally, weight loss, electrochemical tests, FTIR, 1H NMR, 13C NMR, EDS, surface morphology analysis, hardness assessments, thermal stability studies, and contact angle measurements were conducted. Computationally, density functional theory (DFT) and an inhibitory mechanism were proposed to explain the inhibitor–metal surface interactions. The study demonstrated that COMI significantly reduced corrosion rates in 1M HCl, achieving an inhibition efficiency of 98.42% at a concentration of 80 ppm and a temperature of 60 °C. The inhibitor was found to form a protective layer on the mild steel surface, influencing both anodic and cathodic corrosion processes. This protective layer formed spontaneously, consistent with the Langmuir adsorption isotherm. The Gibbs free energy (ΔGads) was calculated to be −28.81 kJ/mol, indicating that COMI adsorbed spontaneously onto the mild steel surface through both physical and chemical adsorption mechanisms. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) images confirmed the existence of this protective layer. The addition of 80 ppm COMI reduces the surface roughness from 2.12 to 0.28 μm. Computational studies further validated the experimental findings, confirming the formation of bonds between COMI and the mild steel surface.

Extraction and Characterization of Cellulose from Kelp (Laminaria japonica) Residue

Abstract Kelp residue is the byproduct of industrial production of sodium alginate from kelp. An in-depth utilization of kelp residue not only creates higher economic value but also opens up a new pathway for comprehensive utilization of kelp. In this study, a method of first removing acid-soluble ash and then depleting protein was employed to extract cellulose components from kelp residue. Single-factor experiments demonstrated that treating kelp residue with 1.2 mol/L hydrochloric acid at a solid-liquid ratio of 1:5 effectively removed acid-soluble ash. Subsequently, further treatment with 3% NaOH at a solid-liquid ratio of 1:10, conducted at 100 °C for 140 minutes, reduced the protein content in the extract to below 1%, with a cellulose yield of 33.5%. Fourier transform infrared spectroscopy analysis revealed that characteristic peaks attributed to cellulose existed in the extractive, while electron microscopy observations indicated that the extracted kelp residue cellulose exhibited irregular thin-sheet structures. The cellulose obtained in this study lays the foundation for its further utilization and processing into cellulose-derived products.

Moderate strategy for efficient recovery of rare earth elements from scintillation crystal waste

The lutetium has been known to be used in medical imaging materials, but its scarcity in the Earth’s crust makes it expensive. In this work, we present a process for efficient lutetium recovery from the lutetium-yttrium oxyorthosilicate crystals (LYSO) waste. The process involves preliminary mechanical activation, followed by rare earth extraction via acid leaching. The key factors for activation and leaching were studied and optimized. The mechanism of mechanical activation promoting rare earth leaching was revealed by employing the characterizations of morphology and crystal structure of LYSO. It was found that the mechanical activation process could destroy the crystal structure of LYSO waste, forming numerous amorphous phases and grain boundaries, which facilitated the breaking of existing bonds and mass transfer of acid. It was also discovered that the formation of silica gel during leaching impedes the leaching of rare earth, and low concentrations of hydrochloric acid, combined with stirring during acid leaching, could reduce the impact of silica gel. Ultimately, following a mechanical activation pretreatment at 300 rpm for 90 min, 98.7 % of lutetium could be leached after 60 min of acid leaching in 3 mol/L hydrochloric acid. This process addresses the problems associated with high energy consumption and excessive usage of acidic and alkaline reagents in conventional recycling techniques. Compared to conventional methods, the mechanical activation-acid leaching method has a minimum economic benefit improvement of 20.8 % in the process of recovery from LYSO waste. It offers an alternative and more energy-efficient and economical recycling route for waste scintillation crystals.

Nitrosamine mitigation: NDMA impurity formation and its inhibition in metformin hydrochloride tablets

The mitigation of nitrosamine formation in drug products has been studied and approaches such as using formulations with pH modifiers and antioxidants have been shown to decrease the formation of nitrosamines. However, more studies are needed to explore the effectivness of mitigation strategies with different drug models and formulations. The primary objective of this work was to assess the role of different antioxidants and pH modifiers in tablet formulations to mitigate the formation of NDMA, prepared in-house, using metformin hydrochloride as a model drug. A study design for manufacturing metformin hydrochloride formulations was created to evaluate potential mitigation stratigies. The formulations were prepared by wet granulation that included a sodium nitrite spike and various antioxidants such as ascorbic acid, caffeic acid and ferulic acid at various concentrations that may inhibit nitrosamine formation. The study design also included pH modifiers such as hydrochloric acid and sodium carbonate. The metformin hydrochloride formulations were placed under stability conditions that included humidity, temperature and time over a six month period. NDMA inhibition was found to be most effective in formulations with basic pH, followed by the addition of tested antioxidants with 0.1% concentrations in the formulations. All tested antioxidants showed complete mitigation in formulations with 0.5% and 1% concentrations. In summary, basic pH and the inclusion of antioxidants exhibited the potential to mitigate the formation of NDMA in metformin hydrochloride tablets.

Soft soap and linalool as potential management tools for Philaenus spumarius (Hemiptera: Aphrophoridae), vector of Xylellafastidiosa

Philaenus spumarius (Hemiptera: Aphrophoridae) is one of the most polyphagous xylem-feeding pests. It recently acquired bad fame when it was identified as the main vector of the bacterium Xylella fastidiosa, the causal agent of the Olive Quick Decline Syndrome that, within ten years, has affected and led to the death of more than 21 million olive trees in the Southern Italian region Apulia alone. Despite the agricultural practices and synthetic insecticides available, as not sufficiently effective, more strategies to target all the developmental instars of the pest and eco-friendly formulations, especially in organic orchards, are urgently needed. Therefore, the main goals of this work were to test the toxicity of a solution of potassium salts of fatty acids (soft soap) on P. spumarius juveniles and assess the attractiveness exerted by linalool on adults in a planar olfactometer. According to our results, the average neanids/nymphs’ mortality was 82.2 ± 10.4% 24h after spraying the soft soap on them at the labelled dose. Regarding the adults, linalool was significantly attractive to both sexes in a concentrations range between 0.01 and 0.12 μL linalool L−1 air. Our purpose is to potentially suggest a dual, integrated control approach against P. spumarius, with the soft soap as a biopesticide to reduce the immature stages of the pest and attractive, linalool-activated traps to numerically cull the population of the meadow spittlebug as part of a broader management system.

Synthesis and Investigation of Polymers Containing Different Ratio of Quinonediiminic and Benzenoid Units in PANi‐Like Structure

AbstractThis study presents, for the first time, a new method for the synthesis of polymers containing different ratios of oxidized quinoid and reduced benzenoid units in polyaniline (PANi)‐like structure. Copolymers were synthesized by an oxidative copolymerization method of p‐phenylene diamine (p‐PDA) and o‐anisidine (o‐An) in an organic medium using different initial compositions of monomers. The compositions of the copolymer were determined based on 1H NMR spectral data. The thermal stability, electrical conductivity, morphology, and solubility were studied and a comparative analysis with polyaniline and corresponding homopolymers was been carried out. The thermal behavior of copolymers was studied using thermogravimetric analysis and differential scanning calorimetry. It was found that during heating one endothermic process of water evaporation and two exothermic processes occur, which depend on copolymer composition, and only 30% weight loss occurs up to 600 °C. It is shown that room‐temperature conductivity of copolymers doped with hydrochloric and sulfuric acids ranges from 10−5 to 10−3 S cm−1 and increases with increasing concentration of o‐anisidine structural units. The conductivity of iodine‐doped copolymers is of the same order as the conductivity of iodine‐doped PANi in emeraldine and leucoemeraldine forms. The morphology of doped copolymers depends on the co‐monomer ratio and the type of dopants.

Strategically Modulating Proton Activity and Electric Double Layer Adsorption for Innovative All-Vanadium Aqueous Mn2+/Proton Hybrid Batteries.

Aqueous Mn-ion batteries (MIBs) exhibit a promising development potential due to their cost-effectiveness, high safety, and potential for high energy density. However, the development of MIBs is hindered by the lack of electrode materials capable of storing Mn2+ ions due to acidic manganese salt electrolytes and large ion radius. Herein, the tunnel-type structure of monoclinic VO2 nanorods to effectively store Mn2+ ions via a reversible (de)insertion chemistry for the first time is reported. Utilizing exhaustive in situ/ex situ multi-scale characterization techniques and theoretical calculations, the co-insertion process of Mn2+/proton is revealed, elucidating the capacity decay mechanism wherein high proton activity leads to irreversible dissolution loss of vanadium species. Further, the Grotthuss transfer mechanism of protons is broken via a hydrogen bond reconstruction strategy while achieving the modulation of the electric double-layer structure, which effectively suppresses the electrode interface proton activity. Consequently, the VO2 demonstrates excellent electrochemical performance at both ambient temperatures and -20°C, especially maintaining a high capacity of 162mAhg-1 at 5Ag-1 after a record-breaking 20000 cycles. Notably, the all-vanadium symmetric pouch cells are successfully assembled for the first time based on the "rocking-chair" Mn2+/proton hybrid mechanism, demonstrating the practical application potential.

A novel bio-based ferric flame retardant effectively improving the flame retardancy and mechanical properties of polylactic acid

PTDF is prepared by a convenient ionic reaction of phytic acid, terephthalic dihydrazide and iron salts in water. PTDF has high phosphorus and nitrogen content and good thermal stability, which can effectively improve the flame retardancy of PLA. PTFE is an anti-drip agent and is often used to improve the flame retardancy of PLA together with flame retardants. The addition of 4 wt% PTDF and 0.1 wt% PTFE made PLA reach V-0 flame retardant grade from non-flame retardant, and the oxygen index increased from 19.5 % to 24.5 %. With the increase of PTDF content, the performance of PLA improved significantly. The peak heat release rate (PHRR) and THR of PLA/6PTDF composites decrease by 27.4 % and 16.2 %, respectively, and the flame retardant index FRI increase by 232 %, showing excellent flame retardant efficiency. 6 wt% PTDF can increase the crystallinity of PLA by 25.9 %, tensile strength, maximum force required for impact fracture and notch impact strength by 12 %, 37 % and 129 %, respectively, and effectively improve the mechanical properties and toughness of the composite. The bio-based flame-retardant PLA/PTDF composites reported in this paper can be applied to office equipment.

Efficient one-pot tandem C-C formation reaction catalyzed by a multi-functionalized polyacrylonitrile fiber catalyst

A simple and straightforward method has been proposed in this work to construct a multi-functionalized polyacrylonitrile fiber catalyst containing carboxylic acid, tertiary amine, and quaternary ammonium salt to enable series one-pot C-C bond formation in water. The fiber catalyst was prepared from polyacrylonitrile fiber using a two-step method and characterized using various detection techniques. Furthermore, the activity of multi-functional synergistic catalysts can be controlled by adjusting the ratio of acid and base. It is noteworthy that the polyacrylonitrile fiber catalyst with an acid-base ratio of 3:1 (PANF-ABNCl3/1) exhibited superior catalytic activity and high yield in a variety of C-C generation reactions. Additionally, the PANF-ABNCl3/1 catalyst demonstrated exceptional recyclability (at least 10 times) and performed well in scale-up (7.4g, 96%) and continuous flow experiments (can be used continuously for 7 × 24h) using kettle and tubular fixed bed reactor respectively. These findings suggest that the PANF-ABNCl3/1 catalyst holds promise for industrialization.