A Computational Study on the Ca2+ Solvation, Coordination Environment, and Mobility in Electrolytes for Calcium Ion Batteries

Calcium (ion) batteries are promising next-generation energy storage systems, owing to their numerous benefits in terms of performance metrics, low-cost, mineral abundance, and economic sustainability. A central and critical area to the advancement of the technology is the development of suitable eletrolytes that allow for good salt solubility, ion mobility, electrochemical stability, and reversible redox activity. At this time, the study of different solvent-salt combinations is very limited. Here, we present a computational study on the coordination environment, solvation energetics, and diffusivity of calcium ions over a range of pertinent ionic liquids, cyclic and acylic alkyl carbonates, and specific alkyl nitriles and alkyl formamides, using the salts calcium bis(trifluoromethylsulfonyl)imide (Ca(TFSI)2) and calcium perchlorate (Ca(ClO4)2). Key findings are that several solvents from different solvent classes present comparable solvation environments and mobilities. Ca(TFSI)2 is prefered over Ca(ClO4)2 owing to the former’s mix coordination of Ca2+ to O and N atoms. Ionic liquids with alkyl sulfonate anions provide better coordation over TFSI, which leads to greater diffusivity. Binary organic mixtures (carbonates) provide the best solvation of Ca2+, however, single organic solvents also provide good solvation, such as EC, THF and DMF, as well as some acyclic carbonates. Ion pairing with the salt anion is always present, but can be mitigated through solvent selection, which also correlates to greater mobility; however, there are examples in which strong ion pairing is not significantly adverse to diffusivity. The solvent incorporate into the solvation structure with binary organic mixtures correlates well with the solvation capabilities of the individual solvents. Finally, we show that ionic liquids (specifically alkyl imidazole (cation) alkyl sulfonate (anion) ionic liquids) do not decompose when coordinating at a Ca metal interface, which indicates its promising stability. Overall, this study contributes further generalized understanding of the correlation between solvent and salt and the resultant Ca2+ complexes and Ca2+ mobility in a range of electrolytes, and reveals a range of possible solvents suitable for exploration in calcium (ion) batteries.

A Computational Study on the Ca2+ Solvation, Coordination Environment, and Mobility in Electrolytes for Calcium Ion Batteries

Calcium (ion) batteries are promising next-generation energy storage systems, owing to their numerous benefits in terms of performance metrics, low-cost, mineral abundance, and economic sustainability. A central and critical area to the advancement of the technology is the development of suitable eletrolytes that allow for good salt solubility, ion mobility, electrochemical stability, and reversible redox activity. At this time, the study of different solvent-salt combinations is very limited. Here, we present a computational study on the coordination environment, solvation energetics, and diffusivity of calcium ions over a range of pertinent ionic liquids, cyclic and acylic alkyl carbonates, and specific alkyl nitriles and alkyl formamides, using the salts calcium bis(trifluoromethylsulfonyl)imide (Ca(TFSI)2) and calcium perchlorate (Ca(ClO4)2). Key findings are that several solvents from different solvent classes present comparable solvation environments and mobilities. Ca(TFSI)2 is prefered over Ca(ClO4)2 owing to the former’s mix coordination of Ca2+ to O and N atoms. Ionic liquids with alkyl sulfonate anions provide better coordation over TFSI, which leads to greater diffusivity. Binary organic mixtures (carbonates) provide the best solvation of Ca2+, however, single organic solvents also provide good solvation, such as EC, THF and DMF, as well as some acyclic carbonates. Ion pairing with the salt anion is always present, but can be mitigated through solvent selection, which also correlates to greater mobility; however, there are examples in which strong ion pairing is not significantly adverse to diffusivity. The solvent incorporate into the solvation structure with binary organic mixtures correlates well with the solvation capabilities of the individual solvents. Finally, we show that ionic liquids (specifically alkyl imidazole (cation) alkyl sulfonate (anion) ionic liquids) do not decompose when coordinating at a Ca metal interface, which indicates its promising stability. Overall, this study contributes further generalized understanding of the correlation between solvent and salt and the resultant Ca2+ complexes and Ca2+ mobility in a range of electrolytes, and reveals a range of possible solvents suitable for exploration in calcium (ion) batteries.

Change of electrical characteristics of rubber in the process of “swelling–deswelling”

Objectives. The main indicator that determines electrical conductivity of rubbers is specific volumetric electrical resistance (ρv ). The purpose of this work is to investigate changes in this indicator during swelling and deswelling of electrically conductive rubbers. When considering the swelling process of rubbers in liquid media at a molecular level, an analogy of this process with mechanical deformation of the material is drawn and common features and differences of these processes are revealed.Methods. For rubber compositions based on paraffinate and alkyl sulfonate nitrile butadiene rubbers, the degree of their swelling and the change in linear dimensions in heptane and in gasoline grades 80, 92, and 95 were determined. The ρ v value was determined by a potentiometric method: the initial value was measured after temperature control of rubbers for 1 h at 120°C, and the second measurement was carried out after these rubbers were swollen in the solvents for 48 h, followed by drying at 20°C to a constant weight and repeated temperature control under the same conditions. Using an IR Fourier spectrometer, spectra of the solvents used were obtained before and after identification of the investigated rubber samples in them.Results. It was shown that the type of rubber and solvent used influence the degree of rubber swelling. Rubber compositions based on natural rubbers with a large amount of attached acrylonitrile, obtained in the presence of an alkyl sulfonate emulsifier, have the highest resistance to swelling. The effect of the used solvent on the change in the degree of swelling is determined by its affinity for rubber and the presence of polar additives that increase the octane number of gasoline. It was established that the linear change of the samples upon swelling in the indicated solvents varies according to the length and thickness of the samples. Results show that depending on the type of rubber used and the degree of its filling, the described rubber processing technology leads to a decrease in the ρ v value by 2 to 20 times. The greatest effect of ρ v reduction is observed in low-filled rubber compositions based on paraffinate nitrile rubbers. The spectra of the frustrated total internal reflection of the solvents after their interaction with the studied rubbers show that particulate extraction of dibutyl phthalate, which was used as a plasticizer in rubber compounding, takes place as a result of rubber swelling.Conclusions. The proposed method of rubber processing reduces the ρ v value by removing dibutyl phthalate from the studied rubbers and forming a more developed carbon–elastomer structure. Furthermore, it solves the problem of the negative effect of the plasticizer on the ρ v value of rubber without excluding it from the rubber composition.

Commentary on “time-dependent selected reaction monitoring-based GC-MS/MS method for estimation of genotoxic impurities in a new antibacterial agent: alalevonadifloxin mesylate”

The references cited in this article to justify the analysis of alkyl mesylates in alalevonadifloxin mesylate (ALA) are considered totally inappropriate since they all present evidence showing that such esters are not formed during the synthesis of a sulfonic-acid salt using an alcohol as solvent. Relevant mechanistic and kinetic data, first published over a decade ago, demonstrate that no alkyl-sulfonate impurities are produced when an equimolar amount of methanesulfonic acid is added to the base form of a drug substance dissolved in ethanol (or a similar alcohol solvent), and so confirmatory assay data should not be required.

PENURUNAN KEKERUHAN, KADAR LAS DAN FOSFAT LIMBAH CUCIAN RUMAH TANGGA DENGAN METODE KOMBINASI PENGOLAHAN KOAGULASI DAN PROSES OKSIDASI LANJUT SISTEM UV/H2O2

Peneliatian ini adalah penelitian eksperimen yang bertujuan untuk menganalisis kekeruhan, kadar LAS (Linier Alkyl Sulfonate) dan fosfat pada limbah cucian rumah tangga di salah satu pemukiman padat penduduk di kawasan Kota Singaraja sesuai Keputusan Menteri Negara Lingkungan Hidup KEP 51/MENLH/10/1995. Subjek penelitian ini adalah limbah cucian rumah tangga di salah satu pemukiman padat penduduk di kawasan Kota Singaraja, sedangkan objek dari penelitian ini adalah kekeruhan, kadar LAS (Linier Alkyl Sulfonate) dan fosfat. Penelitian ini menggunakan metode koagulasi dengan koagulan FeCl3. Metode koagulasi ini untuk menentukan pH dan konsentrasi optimum FeCl3 dikombinasikan dengan proses AOP sistem UV/H2O2 untuk menurunkan kekeruhan, kadar LAS dan fosfat pada limbah cucian rumah tangga. Sebelum percobaan dilakukan, kekeruhan, kadar LAS dan fosfat ditentukan terlebih dahulu nilai kekeruhan awal limbah cucian rumah tangga tersebut sebelum diberikan perlakuan yaitu 164 NTU, kadar LAS awal tanpa perlakuan yaitu 2,659 mg/L, dan kadar fosfatt awal tanpa perlakuan 0,988 mg/L. Kondisi optimum pada proses koagulasi untuk pengolahan limbah cucian rumah tangga dengan penambahan 25 mL koagulan FeCl3 2% pada pH 4. Efisiensi penurunan kekeruhan LAS dan fosfat berturut-turut pada kondisi tersebut adalah 90,7%, 72,9% dan 89,2%.Efisiensi penurunan kekeruhan, kadar LAS dan fosfat dari proses dengan Proses AOP Sistem UV/H2O2 berturut-turut adalah 72,5% , 93,3% dan 96,2% Efisiensi penurunan nilai kekeruhan, kadar LAS dan fosfat dari kombinasi proses koagulasi dan AOP sistem UV/H2O2 berturut-turut sebesar 97,4%, 98,1% dan 99,5%.

PEMANFAATAN DAUN WARU (Hibiscus tiliance L) SEBAGAI BAHAN BAKU DETERJEN

SLS (Sodium Lauryl Sulfate) and LAS (Linear Alkyl Sulfonate) are active ingredients in detergents which have a negative impact on living things and the environment. To overcome these problems, one of the environmentally friendly alternative ingredients is waru leaves. The purpose of this study was to determine the benefits of waru leaves in their use for washing cloth, knowing the effectiveness of waru leaves as an active ingredient in cleaning stains and knowing the level of contamination of COD waste waru leaf extract. The composition of the detergent formula uses the experimental method with 1 factor, namely the concentration of waru leaves (80%, 82%, 84%, 86%, 88%). The sample selection stage is based on the parameters of pH, foam height, optimal viscosity. From this stage, two best formulas were obtained, namely 80% and 82% waru leaf extract. The two best samples were washed so that the best formula was 82%. Further testing is carried out to measure the level of waste contamination. The sample had a pH of 7.56, foam height of 4.10 cm, viscosity of 539.0, white degree of WI-CIE 155.02 and level of COD contamination of 308.25 mg / l. These results can prove that waru leaves can be used as detergent raw materials.