Stripping Conditions Research Articles

Nucleation Behavior of Pitting and Evolution of Stripping on Lithium Metal Batteries

The stripping reaction of lithium will greatly impact the cyclability and safety of Li metal batteries. However, lithium pits' nucleation and growth, the origin of uneven stripping, are still poorly understood. In this study, we analyze the nucleation mechanism of Li pits and their morphology evolution with a large population and electrode area (>0.45 cm2). We elucidate the dependence of pit size and density on current density and overpotential, which is aligned with classical nucleation theory. With laser scanning confocal microscope, we reveal the preferential stripping on certain crystal grains and a new stripping mode between pure pitting and stripping without pitting. Descriptors like circularity and the aspect ratio (R) of pit radius to depth are used to quantify the evolution of lithium pits in three dimensions. As pits grow, growth predominates along the through-plane direction, surpassing the expanding rate at the in-plane direction. After analyzing more than 1000 pits at each condition, we validate that the overpotential is inversely related to the pit radius and exponentially related to the rate of nucleation. With this established nucleation-overpotential relationship, we can better understand and predict the evolution of surface area and roughness of lithium electrodes under different stripping conditions. The knowledge and methodology developed in this work will significantly benefit lithium metal batteries' charging/discharging profile design and the assessment of large-scale lithium metal foils. DOI of publication: 10.1021/acsami.4c01530Acknowledgments: H.Z., M.U., and F.S. thank the support from the Assistant Secretary for Energy Efficiency and Renewable Energy, Office of Vehicle Technologies of the US Department of Energy through the Advanced Battery Materials Research Program. F.S. thanks the support from the National Science Foundation under Grant No. 2239690.

Electrochemical sensor for the analysis of 5-hydroxymethylcytosine in the presence of cytosine using pencil graphite electrode

In recent years, important efforts have been made to elucidate the mechanisms of epigenetic regulation, and one of the most studied epigenetic modifications was DNA methylation/demethylation. In this study, the voltammetric behaviour of 5-hydroxymethylcytosine was studied in the pH range of 2.00–11.00 using pencil graphite electrodes by differential pulse and square wave voltammetry. The effect of buffer solutions, scan rate, square wave voltammetry parameters, and stripping conditions on the voltammetric responses of 5-hydroxymethylcytosine were performed. The electrochemical oxidation process of 5-hydroxymethylcytosine on the pencil graphite electrode was realized under adsorption control. In human urine, by square wave stripping voltammetry, 5-hydroxymethylcytosine was quantified in a concentration range of 1.00 × 10−5 M-2.00 × 10−4 M. The proposed method was tested in the presence of cytosine in human urine. The recovery value of 5-hydroxymethylcytosine was found to be 99.57 %.

High rate methanogenesis and nitrogenous component transformation in the high-solids anaerobic digestion of chicken manure enhanced by biogas recirculation ammonia stripping

High-solids anaerobic digestion is a promising technology for treating animal manure. However, the high nitrogen content in chicken manure leads to severe ammonia inhibition, thereby hindering the application of this technology for chicken manure. This study operated a high-solid anaerobic system feeding the reactor with 20 % total solids (TS) chicken manure for 650 days to investigate whether the anaerobic metabolic performance could be enhanced by adopting biogas recirculation ammonia stripping. The results show that, with ammonia stripping, the total ammonia nitrogen (TAN) was reduced from 8.2 to 3.0 g/L. The methanogenic activity was enhanced 1.3 – 2.9 fold. This led to a low level of volatile fatty acids (VFA, 0.6 g/L) and a high methane yield of 0.3 L/g-volatile solids (VS). Protein decomposition was facilitated under stripping conditions and correlated with a higher abundance of protein decomposition bacteria and enhanced methane production. The dynamics of ammonium formation and removal were illustrated for different stripping conditions. The ability to maintain low ammonium and the carbon and nitrogen balance was also verified. The proven effectiveness observed in this long continuous experiment may provide a foundation for further demonstrating the high-solids anaerobic digestion of chicken manure.

Deconvoluting Effects of Lithium Morphology and SEI Stability through Interface Engineering

The widespread use of renewable energy resources and electrification is mandatory for transitioning into a fossil-fuel-free world. Currently, Li-ion battery (LIB) is the universal mode of electrochemical energy storage, but it is reaching the theoretical limit, creating the urgency of more efficient batteries for next-generation applications. Li-metal batteries (LMBs) are considered a key technology to overcome the current energy density limitations of LIBs. In the most energy-dense LMB configuration, the anode-free LMB, Li is directly plated on and stripped from the Cu current collector (CC), subjecting it to the most stringent cycling conditions and making performance regulation crucial. Therefore, engineering the Cu-electrolyte interface is both fundamentally and practically significant.The two most crucial performance modulators in LMBs are electrodeposited Li morphology and solid electrolyte interphase (SEI). The literature has shown that low surface area morphology and anion-derived SEIs are usually beneficial for improved performance. However, it is difficult to deconvolute the individual impact of low surface area morphology and anionic SEI species on performance as they coexist and are correlated. One reported approach to understand the decoupled effects of morphology and SEI is ultrafast electrodeposition of lithium outpacing SEI formation (>100 mA cm-2). Our work establishes a new approach applicable at regular plating and stripping conditions (1 mA cm-2) that uses interface engineering with atomic layer deposited (ALD) thin films to deconvolve Li morphology and SEI stability effects. First, we modify the Cu CC surface using two different thin films with distinct characteristics: resistive, acidic HfO2; and conductive, acidic ZnO.Leveraging ALD, we precisely control the thickness of the nanofilms and establish that increasing the film resistance results in improved performance due to resistance-derived Li morphology. Our approach of decoupling the impact of SEI species from morphology is to preform the SEI before cycling using a simple potential hold step for both these acidic films with opposite electrical properties at different thicknesses. We find that with increasing film thickness, generally, the preformed SEI has more anionic species due to the surface acidity of the thin films. Despite being anion-rich, the preformed SEI does not improve performance, which we attribute to its evolution into an organic-rich SEI during plating. Moreover, the impact of the preformed SEI is statistically insignificant during long-term cycling, whereas the role of resistance becomes more apparent. The effects are demonstrated through interface characterization and performance measurements in three different electrolytes, with at least a twofold increase in cycle life and improved capacity retention achieved in practical anode-free pouch cells. Our results thus indicate that morphological control is more effective for improved battery cyclability due to the inherent challenges with preformed SEI preservation, and as a result the resistance of the thin films is more important than surface acidity for CC modification.

Ammonia recovery via stripping from hydrothermal liquefaction aqueous from sludge for anaerobic co-digestion pretreatment

Hydrothermal liquefaction (HTL) is a thermo-chemical method of processing wastewater solids that could be preferential over anaerobic digestion (AD) because it produces a greatly reduced volume of solids. Instead, the effluent can be separated into biocrude refined into fuel, hydrochar a carbon-rich solid and HTL aqueous waste. Unfortunately, HTL aqueous is high in ammonia, phenolics, and nitrogen heterocyclic compounds that can inhibit AD if used for treatment. Ammonia stripping was tested for pretreatment of HTL aqueous from dewatered mixed sludge at 350 °C, 15 min and recovering ammonia. Seven stripping reactor conditions were run, and the best results were seen at 85 °C, a pH of 9.3 and 500 mL/min air flow rate. This case achieved ammonia and total phenolic compounds removal of 79.5 ± 0.1 and 32 ± 1 %, respectively, in 4 h. The ammonia stripping was coupled with acid adsorption to produce an ammonium sulphate salt with fertilizer value. The ideal ammonia stripping conditions produced a salt with a purity of 98.0 ± 0.05 % and represented an ammonia recovery of 73.9 ± 0.04 %. Semi-continuous flow bench-scale thermophilic anaerobic co-digestion of HTL aqueous with municipal sludge found that 12 % of influent chemical oxygen demand (COD) can come from HTL aqueous without inhibition if pretreated with ammonia stripping, while the digester fed with a similar COD from non-pretreated HTL aqueous showed inhibition. Under mesophilic conditions, semi-continuous flow anaerobic co-digestion was successful for non-pretreated and pretreated HTL aqueous even with 24 % and 22 % of influent COD provided by HTL aqueous, respectively.

Stacking pattern transition caused by submarine channel inception and internal levée development

ABSTRACTThe shift from highly amalgamated and laterally offset to aggradational and vertically stacked submarine channels is a pattern that has been widely recognized in seismic reflection datasets as well as in outcropping successions worldwide. However, the sedimentary and stratigraphic details of such an important part of channel evolution and its implications have not been discussed extensively. That gap is addressed here by characterizing a previously undocumented, seismic‐scale outcrop of the Tres Pasos Formation (Magallanes Basin, Chile) that records the transition from a laterally offset/low‐aggradational channel complex to a vertically stacked aggradational complex associated with the development of an internal levée that enhanced channel aggradation. The boundary between the two complexes is defined by a composite erosional surface (up to ca 35 m relief) with two adjacent element‐scale channelized incisions with contrasting sedimentary infills that provide unprecedented insight into this key phase of submarine channel evolution. Observations indicate that, in between these two depositional architecture styles, there is a significant phase of deep incision and bypass. The relief achieved via this deep incision of one or multiple simultaneously active conduits is interpreted to be necessary to set up the conditions for flow stripping and, subsequently, overbank deposition. Finally, the siltstone‐rich intra‐channel lithofacies association observed directly overlying part of the incision is interpreted to represent the stratigraphic expression of the earliest deposits of an active submarine channel preserved due to the abrupt abandonment of this pathway and the development of an adjacent conduit, which resulted in the former being covered with fine‐grained overbank deposits.

Nucleation of Pitting and Evolution of Stripping on Lithium-Metal Anodes.

The stripping reaction of lithium (Li) will greatly impact the cyclability and safety of Li-metal batteries. However, Li pits' nucleation and growth, the origin of uneven stripping, are still poorly understood. In this study, we analyze the nucleation mechanism of Li pits and their morphology evolution with a large population and electrode area (>0.45 cm2). We elucidate the dependence of the pit size and density on the current density and overpotential, which are aligned with classical nucleation theory. With a confocal laser scanning microscope, we reveal the preferential stripping on certain crystal grains and a new stripping mode between pure pitting and stripping without pitting. Descriptors like circularity and the aspect ratio (R) of the pit radius to depth are used to quantify the evolution of Li pits in three dimensions. As the pits grow, growth predominates along the through-planedirection, surpassing the expanding rate in the in-plane direction. After analyzing more than 1000 pits at each condition, we validate that the overpotential is inversely related to the pit radius and exponentially related to the rate of nucleation. With this established nucleation-overpotential relationship, we can better understand and predict the evolution of the surface area and roughness of Li electrodes under different stripping conditions. The knowledge and methodology developed in this work will significantly benefit Li-metal batteries' charging/discharging profile design and the assessment of large-scale Li-metal foils.

Elucidation of the extraction of trivalent actinides using the DOHyA-HDEHP system: an experimental and theoretical approach.

A combined solvent system composed of an acidic and a neutral extractant is demonstrated as an effective system for the mutual separation of lanthanides and actinides from nitric acid solutions. The geometry and stability of various possible complexes formed under extraction and stripping conditions in a combined solvent system composed of N,N-dioctyl hydroxyacetamide (DOHyA) and bis(2-ethylhexyl)phosphoric acid (HDEHP) in the n-dodecane medium were studied both experimentally and theoretically. Experimental observations of the distribution ratios of Am(III) and Eu(III) in the combined solvent system revealed synergistic extraction of trivalent metal ions at all nitric acid concentrations. Density functional theory (DFT) calculations were employed to understand the geometric and electronic properties of the ligands and their corresponding complexes with Am(III) and Eu(III). The calculated results indicate that the feasibility and behaviour of complex formation in the combined solvent system using different methods are based on the energetic aspects of the formation reactions. The study also reveals the participation of the neutral and acid extractants in the combined solvent system facilitating the separation of Eu(III) and Am(III) from high-level liquid waste.

A green dye wastewater treatment process: Complex extraction of Telon yellow 4R from dye wastewater and its application in nylon fabric dyeing

AbstractComplex extraction, which has the characteristics of high efficiency and selectivity of chemicals, has unique advantages in dye wastewater treatment. In the paper, a green closed‐loop dye wastewater treatment route for dyeing industry is re‐evaluated by studying the complex extraction and stripping of Telon yellow 4B, and dyeing test of regenerated dye. FT‐IR characteristic peaks of the initial organic phase and the regenerated organic phase are consistent, and the dye can be migrated from the loaded organic phase to the aqueous phase after stripping. The concentration of dye in the aqueous phase and extraction conditions have a significant effect on extraction rate, especially the aqueous‐organic phase ratio and the pH value of the aqueous phase. Meanwhile, the stripping conditions have a marked impact on stripping rate, among which NaOH dosage is an important factor. The regenerated dye solution and the freshly prepared dye solution at same concentration have the same color shade and K/S value, and the color fastness of dyed fabrics is all above Grade 4. High extraction rate, high stripping rate, excellent reusability of regenerated organic phase, and the dyeing performance of the regenerated dye prove that complex extraction is a green dye wastewater treatment process with the practical feasibility.

Experimental and simulation study on surface material stripping of glass fiber reinforced composites by baking soda abrasive jetting technology

Glass fiber reinforced composites (GFRP) working in a specific environment require regular inspection and maintenance. It is necessary to remove the surface material of fiber reinforced composites to check the fracture of fibers and the damage to matrix that binds fibers in this process. In this paper, the baking soda abrasive jetting was utilized to strip the surface material of glass fiber reinforced epoxy resin (GFREP). The stripping effects of baking soda abrasive jetting technology under different jetting parameters (fiber orientation, jet angle, jet pressure) were explored, and the optimum stripping conditions were determined as parallel to the fiber, 30°, 0.4 MPa. Compared with the chemical stripping method (phenol-dichloromethane), baking soda abrasive jetting can better retain epoxy resin between glass fibers. The LS-DYNA was applied to simulate the erosion process of a single abrasive particle under the optimum stripping condition. The plastic deformation of the matrix and the slight bending deformation of the glass fiber under abrasive impact were observed.

Separation and Recovery of Copper and Nickel in the Leachate of a Waste IC Lead Frame through Synergistic Solvent Extraction Using a Binary Extractant Containing LIX984N and Cyanex302 Followed by Selective Stripping

The IC lead frame is an essential component in semiconductor packaging, primarily composed of a nickel (Ni)–copper (Cu) alloy in which Ni is electroplated onto a Cu substrate. In this study, synergistic solvent extraction using a binary extractant containing LIX984N and Cyanex302, followed by two-stage selective stripping using sulfuric acid (H2SO4) and nitric acid (HNO3) as the stripping agent, was employed to separate and recover Cu and Ni from the leachate of an IC lead frame. The results indicated that under the optimal conditions of synergistic solvent extraction with an extraction pH value of 1, an extractant concentration of 0.015 M LIX984N + 0.0375 M Cyanex302, an extraction aqueous/organic (A/O) ratio of 1:1, and an extraction time of 5 min, the extraction efficiencies for Cu and Ni were 99.8% and 1.17%, respectively. The distribution ratios were DCu 999 and DNi 0.012, resulting in a separation factor of 83,250. In addition, the separation factor was much higher than that of using individual extractant of LIX984N (6208.3) or Cyanex302 (22,185.2). Subsequently, under optimal first-stage stripping conditions, using 0.05 M H2SO4 at a stripping organic/aqueous (O/A) ratio of 1:1, and with a stripping time of 3 min, a stripping efficiency of 99.9% for Ni was achieved. Next, under optimal second-stage stripping conditions, using 5 M HNO3 at a stripping O/A ratio of 2:1, and with a striping time of 3 min, a stripping efficiency of 99.9% for Cu was achieved. Finally, sodium hydroxide (NaOH) was added to the respective stripping solutions to precipitate Ni and Cu ions, followed by calcination treatment for the precipitates to obtain NiO and CuO, respectively. The purity of the former was 99.74% and that of the latter was 99.82%. The results demonstrate that synergistic solvent extraction using a binary extractant containing LIX984N and Cyanex302 can almost entirely extract Cu in the leachate of an IC lead frame at a lower extraction pH and a lower extractant concentration, thus reducing the co-extraction of Ni. In addition, less co-extracted Ni in the organic phase can be selectively stripped using dilute H2SO4, thus reducing the co-stripping of Cu. Hence, the effective separation and recovery of Cu and Ni in IC lead frame leachate can be achieved, which contributes to improving the sustainability of natural resources.

Solvent extraction of scandium from leaching solution of red mud roasted with ammonium sulfate using D2EHPA/TBP

Red mud is an important secondary resource for scandium production. The red mud leaching solution containing scandium in this study was derived from environmentally friendly ammonium sulfate roasting and water leaching process. A synergistic extraction with a mixture of di(2-ethylhexyl) phosphate acid (D2EHPA) and tributyl phosphate (TBP) for recovery of scandium from red mud leaching solution is proposed. The effects of D2EHPA concentration, H2SO4 concentration, rare earth elements, dosage of TBP, phase ratio (A/O), contact time and H2O2 concentration on scandium extraction were investigated. The results show that more than 99% scandium is extracted under the optimal conditions while Fe, Al, Ti, Ca and rare earth elements (Ce, Y, La, Nd, Er, etc.) are hardly extracted. The stripping efficiency of Sc reaches above 92.37% under the optimal stripping conditions of 5 mol/L NaOH with an A/O of 1 at 90 °C for 30 min. The proposed technology could provide an effective method for extraction of scandium from red mud leaching solution.

Ammonia Air Stripping from Different Livestock Effluents Prior to and after Anaerobic Digestion

Livestock digestate provides nutrients and organic matter to the soil while increasing agricultural sustainability. Nevertheless, nitrogen (N) losses due to the nutrient surplus in regions characterized by intensive animal farming activities still represent an unsolved issue. For this purpose, digestate needs proper treatment and management to avoid N losses in the environment. In the livestock farming context, anaerobic digestion (AD) can be accompanied by an ammonia stripping (AS) process for N recovery. This paper aims to investigate the feasibility AS prior to and after AD of the manure, focusing on two different livestock farms, representative of dairy cattle and pig breeding in southern Italy. AS was performed at a lab scale by injecting microbubbles of air, which allowed the pH to increase, and thus the removal of ammonia. The results show that treating a dairy raw slurry with high intermediate alkalinity (IA) (6707 mg CaCO3 L−1) with AS may not be convenient in terms of total ammonia nitrogen (TAN) reduction. As a matter of fact, the loss of buffering capacity during the stripping process resulted in a pH never exceeding the value of 9, which could not promote free ammonia volatilization, whereas integrating AD with AS allowed us to obtain a 34% higher TAN reduction under the same stripping conditions at a temperature (T) of 38 °C and a gas-to-liquid ratio (G/L) of 1:1. Therefore, the AS removal efficiency strongly depends on the characteristics (mainly IA) of the treated matrix. High IA values suggest a possible high concentration of volatile fatty acids, which hinders pH increases and, thus, enables ammonia stripping. Despite the initial matrix origin, a low IA compared to the total alkalinity (TA) (<20% of TA) ensures a greater ammonia removal efficiency, which could be similar between digestate and raw manure in the same operative process conditions. Nonetheless, the amount of ammonia stripped is related to the initial TAN concentration of the specific matrix.

Complete recycling of valuable metals from electroplating sludge: Green and selective recovery of chromium

The recovery of chromium (III) is a key step for complete recycling of heavy metals from electroplating sludge. Therefore, thermodynamic equilibrium diagrams of Me-PO43--H2O[Me: Cr (III), Zn (II), Cu (II), Fe (II), Fe (III), Ni (II)] systems at 298 K have been established, the thermodynamic analysis for the precipitation of chromium (III) using phosphates and the conversion of CrPO4 to Cr(OH)3 using caustic soda were conducted. The results showed that phosphate seemed preferentially combined with Cr (III) rather than other metal cations in order of Cr (III) > Fe (III) > Fe (II) > Zn (II) at the pH range of 1.0 ∼ 5.0. The verification experiment results indicated that about 94.1% Cr (III), 5.51 %Fe (II), and 0.33% Zn (II) reached were precipitated by adding 110% theoretical amount of Na3PO4·12H2O at equilibrium pH equal to 2.0. As consistent with the thermodynamic analysis, alkali conversion of CrPO4 with NaOH achieved a leaching efficiencies of Cr (III) and phosphorus were 5.1% and 90.6%, which realized phosphate recycling and the recovery of leached Cr (III). 99.7% Zn was deeply separated and recovered from Fe (II/III) by D2EHPA by two stages of counter current extraction with an O/A ratio of 1:2, 5 min stirring at 20 °C. And the optimal conditions for Zn stripping were considered as mixing 1 mol/L H2SO4 and loaded D2EHPA with O/A ratio of 5:1 at room temperature for 5 min. The proposed process shows a promising industrial application in view of its low cost, complete recycling, and wide adaptability. SynopsisElectroplating sludge will cause serious pollution to the environment if not properly treated. This study reports a new treatment method of electroplating sludge to achieve comprehensive recovery of all valuable metals. Compared with traditional process, this process exhibits a promising industrial application due to its no emissions, lower cost, complete reagent cycle, purer product, higher quality, broader adaptability, and greener production.

Novel cationic surfactants: synthesis, surface, antimicrobial studies and applicability as an extracting agent for interested element from monazite mineral concentrate

Abstract Two novel cationic surfactants based on palmitic acid were prepared to extract uranium from its fluids. The chemical structures of the surfactants prepared were confirmed spectroscopically. The surface activity of these surfactants was evaluated by measuring their surface tension. The cationic surfactants prepared were also tested for their biological activity against Gram-positive and Gram-negative bacteria and fungi. Subsequently, an attempt was made to use these surfactants to remove uranium from the hydrous oxide cake produced after the alkaline degradation of monazite mineral concentrate. To achieve this goal, several experiments were conducted to determine the optimal conditions for uranium extraction and stripping. Under these optimal conditions, the experimental capacity fitted the pseudo-second order kinetic model. Under the investigated optimal stripping factors of 1 M NaCl, acidified with 0.2 M conc. H2SO4, an A:O ratio of 1:1 and a contact time of 15 min, an uranium stripping efficiency of 83% was obtained for the case study. After the complete stripping process, the marketable uranium concentrate was percipitated using hydrogen peroxide as UO4 H2O with an uranium content of approximately 76%, which was chemically determined and confirmed by EDAX analysis.

Flow Injection Electrochemical Quartz Crystal Microbalance with ICP-OES Detection: Electroprecipitation and Stripping of Lanthanum and Neodymium in a Flow Cell

We used an improved version of our hyphenated analysis technique, flow injection electrochemical quartz crystal microbalance with inductively coupled optical emission spectroscopy (FI-EQCM-ICP-OES), to investigate the electroprecipitation of lanthanum and neodymium from flowing solutions. The improved version has two independent flow injection circuits, allowing different conditions for electrochemical precipitation (pH = 4.3 or 2.6) and quick stripping (2% HNO3) with EQCM mass detection and ICP-OES elemental analysis. Lanthanum or neodymium ions in a 500 μl sample were injected into a carrier stream and deposited onto an electrochemical quartz crystal microbalance (EQCM) housed in a micro flow cell, owing to a localized high-pH layer. The deposits are subsequently stripped from the electrode using HNO3 and analyzed downstream using an ICP-OES. We found that using acidic solutions without supporting electrolyte leads to an increase of the amount of lanthanum detected by 4-fold. The enhanced deposition can be attributed to enhanced mass transfer by migration. Moreover, we showed that by applying chronopotentiometry, we can detect a change in the hydrogen evolution reaction mechanism that enables the precipitation of lanthanides on the surface of the electrode. Understanding and enhancing the deposition of lanthanides is relevant for elemental or isotopic detection in nuclear forensics.

Selective Solvent Extraction of Vanadium Over Chromium from Alkaline Leaching Solution of Vanadium Slag by D2EHPA/TBP

ABSTRACT A selective extraction process for recovering vanadium (IV) over chromium was proposed with use of a mixed extractant consisting of di(2-ethylhexyl) phosphate (D2EHPA) and tri-n-butyl phosphate (TBP). The influence of various factors, which included the initial aqueous pH value, the concentration of leach solution and D2EHPA, phase ratio (O/A), extraction equilibrium time and extraction temperature in the extraction process on the separation of V and Cr was investigated. Under the condition of the optimum extraction, vanadium extraction was above 94.0%. Meanwhile, under the optimum stripping conditions, the vanadium stripping was above 93.0% utilizing 1.5 mol/L sulfuric acid as the effective stripping reagent. The regeneration and reusability of the loaded organic phases after stripping were discussed. In addition, continuous three-stage extraction and stripping strategy indicated that the aggregate loss of vanadium was 0.885% and that the purity of vanadium was more than 99.9%. Under the condition of the optimum precipitation, when the pH value of the stripping solution was adjusted to 7.0 with ammonia water, the precipitation efficiency reached 99.93%. The calcination conditions (above 680 °C in air) were finally determined by TG-DTA and TG-MS experiments, and the V2O5 obtained by calcination was characterized by XRD. Additionally, a method for detecting impurity elements in vanadium matrix without interference was established. The recovery technology has practical significance in enlarging production scale, reducing specific energy consumption and cost, and realizing automatic control in vanadium leaching process.

The Effect of Anionic Surfactant and Stripping Voltammetry on the Signal of Ibrutinib at Nano-Level

Ibrutinib is a selective inhibitor of Bruton’s tyrosine kinase, which is used in chronic lymphocytic leukaemia treatment. In this study, an adsorptive stripping square wave voltammetry was developed to quantify the nanomolar level of ibrutinib in an anionic surfactant medium. The effect of supporting electrolyte, pH, surfactant concentration, and scan rate on the voltammetric peak current and potential of ibrutinib were evaluated using a glassy carbon electrode. The possible electrochemical mechanism was discussed with model compounds. The electrochemical behaviour of ibrutinib shows irreversible and diffusion-adsorption mixed controlled oxidation processes depending on scan rate studies in 0.1 M sulphuric acid. The sensitivity of the method was increased by the combined use of surfactant and stripping conditions. Under optimum conditions, a concentration range of 4.00 × 10−9 to 2.00 × 10−7 M was linear in 0.1 M sulphuric acid, including 2.00 × 10−3 M sodium lauryl sulphate. The limit of detection was calculated as 2.73 × 10−10 M. The proposed method was applied for the quantification of ibrutinib in biological samples. In addition, this method was evaluated in the presence of some potential interference substances.

Supported liquid membranes for the removal of pharmaceuticals from aqueous solutions

In the following study, the extraction of three pharmaceutical compounds: Diclofenac (DCF), ibuprofen (IBP), and carbamazepine (CBZ) by liquid-liquid extraction and their transport by supported liquid membrane (SLM) using different commercial extractants (Cyanex 923 (Cy923), trioctylamine (TOA), tributylphosphate (TBP), and Versatic Acid 10 (neodecanoic acid)) were evaluated.Cy923 was demonstrated to be an efficient extractant for diclofenac and ibuprofen removal through a facilitated transport mechanism from the aqueous feed phase to the aqueous stripping phase using hydroxide ions as stripping agent. Around 80 % of these pharmaceuticals were extracted in 4 h with 10 % of Cy923 and without extreme alteration in the pH. As for carbamazepine, the stripping conditions were achieved with 10 % of Versatic Acid 10. Variation of concentration of different extractants indicates that a higher transport of diclofenac can be obtained by using 40 % of Cy923. In addition, two commercial polymeric supports (PTFE and PVDF) were compared for the selected operational conditions. Finally, the lifetime of the membrane was extended by soaking the polymeric material in the organic solution under vacuum for 24 h and compared with the membrane prepared with an ultrasound-assisted method. Supported liquid membranes present many advantages and can easily be manipulated and integrated for the treatment of persistent pharmaceutical contaminants from water.

Void growth within Li electrodes in solid electrolyte cells

The growth of voids at the electrode/electrolyte interface of a solid state Li battery is analysed by establishing a framework that uses the Onsager formalism to couple the power-law creep deformation of the Li electrode and flux of Li+ through a single-ion conductor solid electrolyte. For realistic combinations of the interfacial resistance and electrolyte conductivity, standard Butler-Volmer kinetics for the interfacial flux does not provide sufficient flux focussing to initiate void growth and so a modified kinetics is adopted where the interfacial resistance is decreased by the presence of dislocations within the creeping Li electrode. Micron-sized pre-existing voids shrink under stripping conditions as flux focussing on the periphery of these voids is always low. However, spatially inhomogeneous creep in the electrode around a hemispherical impurity particle reduces the interfacial resistance with consequent significant flux focussing at the periphery of the impurity. This flux focussing results in void growth with two distinct regimes of behaviour: (i) at low currents stable but small voids form while (ii) at higher currents large voids form but these ultimately collapse. No conditions are identified for which isolated voids are predicted to grow larger than 10μm in size suggesting that cell failure does not occur by the growth of isolated voids. We therefore propose a hypothesis for the coalescence of voids that initiate around impurity particles being deposited on the interface during stripping of the electrode. The ensuing predictions are consistent with measurements of cell failure and provide clues of the failure mechanisms due to void growth.