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The review considers the methods of preparation and the main surface characteristics of magnetic carbon-containing sorbents (MCSs) and summarizes data on the use of MCSs of various origins for the extraction of pharmaceuticals, heavy metals, and dyes from aqueous media. The main factors influencing the adsorption efficiency of MCSs in relation to these pollutants are discussed. It is shown that the extraction of spent MCSs has an advantage over nonmagnetic adsorbents due to their magnetic properties.

The kinetics and mechanism of corrosion of gold anode in a weakly basic aqueous solution of N,N-dimethylpropane-1,3-diamine have been studied by cyclic voltammetry and gravimetry. According to the scanning and transmission electron microscopy data, the corrosion products of gold anode are reduced at both steel and platinum cathodes under galvanostatic conditions to give not only electrolytic gold deposit but also colloidal gold nanoparticles in the electrolyte.

The kinetics of adsorption of 2,4-dichlorophenoxyacetic acid (2,4-D) from an aqueous medium on two microspherical nanoporous carbon materials with different times of activation in a medium of a water vapor is studied. The effect of the redistribution of the porous structure formed during the activation on the process of adsorption is studied. The pseudo-order of adsorption is determined as well, and a comparison of the parameters of the adsorption characteristics with the earlier studied microporous and mesoporous samples is performed.

The kinetics and mechanism of corrosion of an Au anode in a weakly basic aqueous solution of 2,2-dimethyl-1,3-diaminopropane (2,2-DM-1,3-DAP) were studied by gravimetry and cyclic voltammetry. Scanning and transmission electron microscopy was used to determine that under galvanostatic conditions the products of anode corrosion are reduced on a steel cathode with the formation of not only an electrolytic Au deposition on the cathode, but also colloidal gold nanoparticles in the electrolyte medium. The product of the interaction of 2,2-DM-1,3-DAP with atmospheric CO2, namely, the carbamic acid internal salt 3-ammonio-2,2-dimethyl-propylcarbamate, was isolated from the reaction solution.

Recent developments in the use of activated carbons (ACs) of various geneses for wastewater treatment to remove copper, nickel, cadmium, and lead ions, which most frequently occur in industrial and municipal wastewaters, are summarized.

The kinetics of adsorption of salicylic acid from aqueous solutions on microporous granular activated carbon (GAC) was studied. The high adsorption capacity of GAC for this substance was shown. The order of adsorption of salicylic acid and the activation energy of adsorption were determined.

The anodic behavior of gold in solutions containing spirocyclopentyl malonyl peroxide is studied via cyclic voltammetry. It is found that gold dissolves under anodic polarization with the formation of a complex of singly charged cations with spirocyclopentyl malonyl peroxide as a ligand. Gold in this case corrodes at lower potentials (about 500 mV) than in the supporting solution.

The adsorption of 2,4-dichlorophenoxyacetic acid (2,4-D) from aqueous solutions on different porous materials was studied. The materials included micro- and mesoporous carbon matrices of different genesis and metal-organic frameworks (MOFs) of the MIL type such as microporous matrices MIL-53(Al) (AlOHbdc, bdc = benzene-1,4-dicarboxylate) and NH2-MIL-53(Al) (AlOHbdc, abdc = 2-aminobenzene-1,4-dicarboxylate), as well as mesoporous matrix NH2-MIL-101(Al) (Al3O(abdc)3). It is found that the efficiency of liquid phase adsorption is affected by the texture and functionality of the studied materials, whereas in the case of MOFs, the adsorption efficiency is also under the influence the framework flexibility. The MOF materials and mesoporous carbon matrices show a higher adsorption rate than microporous carbon matrices. The flexible microporous MIL-53(Al) framework and microporous coconut shell activated carbon (CSAC) exhibit the highest adsorption capacity with respect to 2,4-D.

For the first time, corrosion of a Pd anode was detected during electrolysis in a weakly alkaline aqueous solution of ethylenediamine. The kinetics and mechanism of the process were investigated by the methods of cyclic voltammetry and gravimetry. Scanning electron microscopy showed corrosion of the Pd anode and deposition of Pd on the cathode surface, while the formation of colloidal Pd in the working solution was identified by transmission electron microscopy.

The kinetics and mechanism of corrosion of Au anode in a weakly basic aqueous solution of 1,2-diaminopropane were studied by gravimetry. According to transmission electron microscopy data, the products of anode corrosion under galvanostatic conditions are reduced on the steel cathode to give not only the electrolytic Au deposit on the cathode, but also colloidal gold nanoparticles in the electrolyte medium. A mixture of four gold complexes with 1,2-diaminopropane was isolated from the reaction solution; the ratio of the complexes and the structure of the predominant complex were proposed on the basis of NMR spectra.

The presence of dimethylacetamide (DMAA) in the composition of electrolytes of a sodium-ion battery destroys the passive film on electrodes and results in a number of reactions not connected with the electrochemical process that must be considered in developing such batteries. Introducing DMAA into the composition of a battery electrolyte greatly improves the conductivity of the polymeric membrane that separates the cathode and anode spaces. However, it is established that in the presence of sodium metal, anhydrous DMAA undergoes Claisen-like self-condensation with subsequent reactions. IR spectroscopy is used to explain the causes of the electrochemical instability of sodium perchlorate solutions in mixed solvents containing DMAA.

The electrochemical reduction of spirocyclopentylmalonyl peroxide in an aqueous medium is studied via cyclic voltammetry on a gold stationary electrode. Based on calculations using parameters of cyclic voltammetry recorded at different scan rates, it is concluded that the studied material underwent two successive one-electron reductions, and a scheme is proposed for its cathodic reduction.

The adsorption of a typical herbicide, 2,4-dichlorophenoxyacetic acid (2,4-D), from its aqueous solution on granular activated carbon (GAC) was studied. The kinetics of adsorption of 2,4-D on GAC and its porosimetric characteristics and microstructure were studied. A high adsorption capacity of GAC for 2,4-D was found.

The corrosion of the Au anode in aqueous solution of 1,4-diaminobutane (DAB) was studied by gravimetric analysis. The corrosion products were found to reduce at a steel cathode under galvanostatic conditions to form electrolytic precipitate of Au. Complex of Au with DAB was found to form in the solution, the structure of the complex was suggested. The kinetic of electrochemical corrosion of the Au anode in the DAB solution was also studied.

This review summarizes the latest developments on the use of activated carbon adsorbents of various geneses for the adsorption of the most common pharmaceuticals in wastewater.

The electrochemical behavior of ascorbic acid (AA) is studied by means of cyclic voltammetry (CVA) and square-wave voltammetry (SWVA) on a boron doped diamond electrode (BDD). The possibility of using the voltammetric response signal to determine quantitatively the concentration of AA in an aqueous solution is shown. An analytical direct correlation function for SWVA at BDD is obtained. It is shown that the detection limit for AA is 1.87 μM. The applicability of SWVA for determining the content of AA in pharmaceutical preparations is demonstrated.

The corrosion of an Au anode in a solution of 1,2-diaminoethane (EDA) is studied by means of gravimetry. It is found that the products of corrosion of an Au electrode under galvanostatic conditions are reduced on a steel cathode with the formation of an electrolytic precipitate of Au. The kinetics of the electrochemical corrosion of gold in an EDA medium is studied. It is shown that a complex of Au with EDA forms in the solution, and its structure is proposed.

The kinetics of adsorption of salicylic acid on Sibunit was studied in an aqueous medium. The order of salicylic acid adsorption and the activation energy of adsorption were studied. The high adsorption capacity of Sibunit for this substance was found.

The kinetics of adsorption of the typical herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) and phenoxyacetic acid (the product of 2,4-D decay in the natural environment) on the activated carbon Sibunit was studied in an aqueous medium. The porosity and surface structure of the carbon were studied. The orders of 2,4-D and phenoxyacetic acid adsorption were determined. The high adsorption capacity of Sibunit for these substances was found.

The electrochemical behavior of phthaloyl peroxide C8H4O4 on an Au disk electrode in a 0.05 M aqueous solution of Na2SO4 was studied by cyclic voltammetry (CVA). It demonstrated a high activity in cathodic reduction with the formation of an irreversible peak on the CVA curve at E =–0.81 V. Additionally, during the anodic oxidation of C8H4O4, the surface of the Au electrode became passivated by compounds which prevented its oxidation during the registration of repeated cycles. Apparently, these compounds are surface complexes of phthaloyl peroxide with a gold cation.

The adsorption of 2,4-dichlorophenoxyacetic acid (2,4-D) as a typical herbicide from aqueous solutions on activated carbons prepared based on polyvinyl chloride by its alkaline dehydrochlorination and the subsequent heat treatment was studied. The structure of the activated carbon surface and the presence of functional groups on it were established. The kinetics of the process of adsorption was studied. The influence of activated carbon preparation conditions on the properties of the adsorbents was demonstrated.

The kinetics of adsorption of 2,4-dichlorophenoxyacetic acid (2,4-D) as a typical herbicide from aqueous solutions on coconut shell activated carbon was studied without preliminary treatment. The surface structure of the activated carbon, which is responsible for its properties, was characterized. The order of reaction in the process of adsorption was determined. The high adsorption capacity of the coconut shell activated carbon was shown.

The kinetics of adsorption of ethyl benzoate from solutions in ethanol on coconut shell activated carbon was studied. It was found that the kinetics of adsorption of ethyl benzoate can be described by pseudofirst-order and pseudo-second-order rate equations with the same accuracy. It was established that the adsorption isotherm at a concentration to 2 g/L in the initial solution is adequately described by the Langmuir equation.

The anodic corrosion of gold followed by its deposition on the cathode as a compact precipitate occurs upon electrolysis of weakly alkaline aqueous solutions of diaminoalkanes, among which 1,2-diaminoethane proved to be the most effective. The process has been characterized by cyclic voltammetry.

A series of flexible metal-organic frameworks (MOFs) belonging to the MIL-53 family, such as MIL-53(Al), its amino-functionalized analog NH2-MIL-53(Al), and MIL-53(Al) type materials with Al3+ ions and mixed benzene-1,4-dicarboxylate and 2-aminobenzene-1,4-dicarboxylate linkers (MixLR) in various proportions were prepared in a nanocrystalline form using MW-activation under atmospheric pressure according to the original solvothermal procedure. The MIL-53(Al) and NH2-MIL-53(Al) samples feature nanocrystals with sizes of 200-300 nm, while MixLR matrices synthesized in this manner are composed of small nanoparticles with sizes of about 20-30 nm. MIL-53(Al) type materials (MIL-53(Al), NH2-MIL-53(Al) and MixLR) were probed in the adsorption of a typical herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) in an aqueous medium. This study revealed a strong impact of the flexibility and porosity of the synthesized MIL-53(Al) type matrices on their physicochemical characteristics. MIL-53(Al) type materials show much higher 2,4-D adsorption rates than an activated carbon matrix (CSAC). The structural characteristics of the studied MIL-53(Al) type materials were established with a high resolution X-ray powder diffractometer equipped with a synchrotron radiation source. The obtained results can be used for the development of advanced adsorbents based on MIL-53(Al) type materials for water remediation.

The corrosion of a Au anode in a solution of 1,3-diaminopropane (DAP) is studied by means of gravimetry. It is found that the products of corrosion of Au electrode in galvanostatic conditions are reduced on a Pt cathode with the formation of either an electrolytic Au deposit or a colloidal solution of metallic Au, depending on the current strength. The kinetics of the dissolution of Au in the presence of DAP is investigated. The formation of a complex of Au with DAP is observed, and a structure for it is proposed.

The kinetics of adsorption of benzoyl peroxide from solutions in ethanol and n-hexane on coconut shell activated carbon was studied. It was found that the kinetics of adsorption of benzoyl peroxide is described by a pseudo-first-order rate equation. The adsorption isotherm of benzoyl peroxide at its equilibrium concentrations from 0.07 to 1.25 g/L in solution is adequately described by the Langmuir equation. It was established that, in a solution in ethyl alcohol, the degradation of benzoyl peroxide with the formation of ethyl benzoate occurred along with adsorption.

The electrochemical corrosion of gold in solutions of 6,6-dimethyl-1,5-diazabicyclo[3.1.0]hexane (I) and 6-methyl-1,5-diazabicyclo[3.1.0]hexane (II) on a gold electrode is studied via cyclic voltammetry. It is shown that the galvanostatic electrolysis of weakly basic aqueous solutions of I and II on gold anodes results in the corrosion of Au electrodes, probably with the formation of organic complexes of gold that are reduced to form a gold mirror on the inner surface of an electrochemical cell during electrolysis. A mechanism is proposed for the investigated processes.

Kinetics of N-chloromethylamine decomposition in an aqueous base medium and chloroform at different temperatures is studied. The decomposition of N-chloromethylamine is found to obey a second order equation in an aqueous base medium at an equimolar ratio of the reagents and a first order equation in chloroform with excess base. The activation energy of N-chloromethylamine decomposition in the both solvents is determined. A mechanism for the reaction is proposed. N-Chloromethylamine is shown to have approximately equal stability in these solvents within the studied temperature range.

The behavior of [1,2-bis(tert-butylperoxy)ethyl]benzene (I) on Pt electrode is studied by means of cyclic voltammetry (CVA). A comparison of the electrochemical properties of I and the properties of previously studied bridge-type 1,2,4,5-tetraoxane ((1,4)-1,4-dimethyl-7-(4-methylbenzyl)-2,3,5,6-tetraoxabicyclo[2.2.1]heptane) (II) shows that the biperoxide studied in this work is reduced on a Pt electrode at lower cathodic potentials and is resistant to electrooxidation.

The kinetics and thermodynamics of the adsorption of diclofenac sodium from aqueous solutions of different concentrations at different temperatures on activated carbon obtained from coconut shell were studied. It was found that the adsorption of diclofenac sodium is described by a pseudo-first-order equation and the adsorption isotherm at its concentration to 750 mg/L in the initial solution is adequately described by the Langmuir equation. It was found that the adsorption of diclofenac sodium is an endothermic process.

Landfills in Germany are currently approaching stabilization phase; as a result removal of inert organics and potentially toxic elements in the leachate is becoming a primary concern. Dissolved air floatation (DAF) at the secondary stage reduces only 27% of the residual chemical oxygen demand (COD) in the investigated treatment systems; downstream granular activated carbon (GAC) units are required to further reduce COD concentration by 40–56% to meet indirect discharge or direct discharge limits respectively. Therefore, in this study performance in terms of COD and trace metals adsorption of different types of granular activated carbon were compared over different contact times and dosages. GAC 1 with Brunauer-Emmett-Teller (BET) surface area of 719.5 ± 2.1 m2/g and average pore diameter (D) of 4.81 nm was identified to be inappropriate for treatment of leachate from this landfill. GAC 2 (with BET of 1513.7 ± 6.4 m2/g and D of 3.50 nm) was feasible for COD reduction from DAF-pretreated leachate, while GAC 3 (with BET of 644.5 ± 2.6 m2/g and D of 5.65 nm) can be coupled either with biological step alone, or as a tertiary step after the DAF unit. Moreover, as COD is the primary remaining contaminant of interest after secondary and tertiary treatment, spectrometer probes provide a close estimation of COD concentration for use in online monitoring. Beside COD removal, GAC 3 also confirmed the effectiveness of trace metals adsorption even at trace level, as it removed 66, 64, 48, 47, 43, and 25% of copper, cobalt, chromium, manganese, nickel, and zinc, respectively.

The removal of tetracycline, carbamazepine, and diclofenac sodium from aqueous solutions by passing them through a column with thermally expanded graphite (TEG), which was synthesized from natural graphite, was studied. The method of numerical simulation was used to determine maximally possible breakthrough volumes for the adsorption of each of the substrates on TEG based on the sensitivity of the method of analysis, which was taken equal to 1.5% of the initial substrate concentration in this work. Conditions for the adsorption of the above substances, which are maximally close to the calculated optimum conditions, were found experimentally.

Thermally expanded graphite, which was obtained from natural graphite as a result of thermal treatment with acids, was used for the removal of tetracycline as a typical antibiotic. The isotherm of adsorption of tetracycline was satisfactorily described by the Langmuir, Temkin, and Freundlich equations. The kinetics of absorption of tetracycline on thermally expanded graphite was studied.

Electrochemical oxidation of tetracycline on a boron-doped diamond electrode in order to develop a method for purification of waste water from contamination by pharmaceutical agents was studied. It was found that under these conditions deep oxidation of tetracycline (TC) down to its full mineralization can take place. Using high resolution mass spectrometry, it was shown that in the first stage of the reaction the oxidation of TC proceeds with the formation of products with higher molecular mass than TC, but with further electrolysis TC transforms into compounds with lower molecular mass, and then into inorganic compounds.

Studies of the electrochemical behavior of hexahydropyrimidine, 1,5-diazabicyclo[3.1.0]hexane, and 1,3-diaminopropane on a gold electrode via cyclic voltammetry allow us to conclude that gold anodes are subject to corrosion in presence these compounds, yielding complexes that migrate into the solutions and discharge on the counter electrode, producing gold metal deposit. 1,5-Diazabicyclo[3.1.0]hexane is found to form complexes with gold that are much more stable that those formed by hexahydropyrimidine and 1,3-diaminopropane.

The electrochemical behavior of hexahydropyrimidine (HHP) on a boron-doped diamond electrode was studied. The obtained data were compared with the results of previous studies on the electrooxidation of HHP on platinum and gold electrodes. It was shown that different products can be obtained from one organic substance using different electrode materials.

The kinetics and mechanism of the deep oxidation of sodium diclofenac on a boron-doped diamond electrode are studied to develop a technique for purifying wastewater from pharmaceutical products. The products of sodium diclofenac electrolysis are analyzed using cyclic voltammetry and nuclear magnetic resonance techniques. It is shown that the toxicity of the drug and products of its electrolysis decreases upon its deep oxidation.

The electrochemical synthesis of 3,12-dimethyl-7,8,15,16-tetraoxadispiro[5.2.5.2]hexadecane (1,2,4,5-tetraoxane) from 1,1-bis-hydroperoxy-4-methylcyclohexane on platinum electrode in a cell with separated and unseparated cathode and anode space in an aprotic solvent is conducted. The kinetics of electrochemical oxidation of 1,1-bis(hydroperoxy)-4-methylcyclohexane is studied. The current yield of the reaction is determined.

The adsorption of a diclofenac sodium medicine from aqueous solutions of different concentrations on expanded graphite, which was obtained as a result of the thermal treatment of graphite with perchloric acid, was studied. The recovery of diclofenac sodium from aqueous solution on expanded graphite was as high as 98–99%.

The regularities of AlkNHBr consumption in the reaction of formation of 1,2-dialkyldiaziridines in aqueous media were studied for the first time by UV spectrometry. The rate constants of particular steps of the reaction were estimated starting from the possibility of formation of the precursor of 1,2-dialkyldiaziridine, N-halogenaminal, due to the amination of the intermediate iminium cation along with the parallel halogenation of the intermediate gem-diamine. The quantum chemical calculations (DFT, B3LYP, 6–31++G(d,p) and 3–21G basis sets) were performed for the spatial and electronic structures of the compounds and indices of the local reactivity and global electrophilicity of the key intermediates of the reactions. The results of the calculations allowed us to explain the retardation of the reaction when using EtNHBr instead of MeNHBr.

The possibility is shown of electrochemical synthesis of 3,12-dimethyl-7,8,15,16-tetraoxadispiro[5.2.5.2]hexadecane that belong to the class of 1,2,4,5-tetraoxanes by oxidation of 1,1-dihydroperoxy-4-methylcyclohexane using a Pt anode.

Electrochemical degradation of diclofenac in aqueous solutions was studied using a thin-film boron-doped diamond electrode deposited onto a niobium plate. The process was monitored by means of UV spectroscopy and elemental analysis.

The hydrolysis of acetylsalicylic acid in the anolyte under the conditions of electrolysis was studied.

Oxidation of tetracycline® in an electrochemical cell with separated cathodic and anodic compartments on smooth platinum was studied. The extent of electrochemical degradation of tetracycline and the energy consumption for eliminating the biological activity of its aqueous solutions were estimated.

Electrochemical synthesis of pentamethylenediazirine at the Pt/Ti anode was conducted. The reaction is reversible. The rate constants of the direct and reverse processes were estimated. The product and current yields of the target compound approach to 100%.