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A preparation of peat humic acids modified by electrochemical treatment in an alkaline medium on iron electrodes was obtained. The effect of the electrochemical treatment on the dispersed composition of the particles of humic substances was determined using dynamic light scattering (quantum correlation spectroscopy). It was found that humic compounds in solution predominantly occur in the form of agglomerates (130–6000 nm), the dispersed composition of which becomes more homogeneous upon electrochemical treatment, and the ability for associative interactions decreases.

Condensed products are obtained via the partial oxidation of iron(II) cations using potassium permanganate, and their physicochemical properties are studied. Samples obtained at a potassium permanganate-to-iron(II) molar ratio close to stoichiometric in a preparation of magnetite have the greatest relative magnetic susceptibility. It is shown that the initial rate of formation of relative magnetic susceptibility in the range of 30–70°C depends linearly on the inverse thermodynamic temperature. Sedimentation of the synthesized products upon exposure to an external magnetic field is complete within 1–1.5 min. Diffractometry shows that crystalline magnetite samples form at a KMnO4 : Fe(II) molar ratio of 0.08–0.18. Magnetic granulometry reveals they have superparamagnetic properties. Under conditions of static sorption, the degree of extraction of chromate ions is 98.7%.

A galvanochemical method for the synthesis of iron lignosulfonate was developed. Metallic iron is gradually dissolved in a solution of lignosulfonates on contact with the material acting as a cathode of the short-circuited galvanic pair. The effect of the cathode material as well as duration and temperature of the process on the anodic dissolution of iron was studied under dynamic and static conditions. Anodic dissolution occurs in a solution of lignosulfonic acids approximately 5 times more rapidly than in a solution of lignosulfonates. Iron lignosulfonate synthesized using the galvanochemical method have high biological activity. Under vegetative conditions, they can be used as an anti-chlorosis preparation to prevent glandular deficiency in plants growing on carbonate soils. Unlike complexonates based on synthetic complexones, iron lignosulfonates are biodegradable and environmentally friendly.

1,1-Dimethylhydrazine is used as a fuel for carrier rockets in the majority of countries implementing space exploration programs. Being highly reactive, 1,1-dimethylhydrazine easily undergoes oxidative transformation with the formation of a number of toxic, mutagenic, and teratogenic compounds. The use of high-resolution mass spectrometry for the study of the reaction of 1,1-dimethylhydrazine oxidation with hydrogen peroxide in aqueous solution allowed us to find hundreds of nitrogen-containing products of the CHN and CHNO classes, formed via radical processes. The vast majority of the compounds have not been previously considered as possible products of the transformation of rocket fuel. We have shown that the oxidation of 1,1-dimethylhydrazine proceeds in two stages, with the formation of a great number of complex unstable intermediates that contain up to ten nitrogen atoms. These intermediates are subsequently converted into final reaction products with a concomitant decrease in the average molecular weight. The intermediates and final products of the oxidative transformation of 1,1-dimethylhydrazine were characterised on the basis of their elemental composition using van Krevelen diagrams and possible compounds corresponding to the most intense peaks in the mass spectra were proposed. The data obtained are indicative of the presence of the following classes of heterocyclic nitrogen-containing compounds among the oxidation products: imines, piperidines, pyrrolidines, dihydropyrazoles, dihydroimidazoles, triazoles, aminotriazines, and tetrazines. The results obtained open up possibilities for the targeted search and identification of new toxic products of the degradation of rocket fuel and, as a result, a more adequate assessment of the ecological consequences of space-rocket activity.

5-Nitro-2-furaldehyde, a new derivatizing agent for the spectrophotometric determination of hydrazine, methylhydrazine, and 1,1-dimethylhydrazine is proposed. It is characterized by high solubility in water and by a substantial difference in the positions of absorption bands of the formed colored derivatives. The kinetics of the reaction of analyte derivatization is studied, and reaction conditions (pH 5, concentration of derivatizing agent 2 mM, 60° C, duration 40 min) are optimized. The limits of detection are 5, 3, and 1.5 μg/L for hydrazine, methylhydrazine, and 1,1-dimetlhydrazine, respectively. A possibility of the spectrophotometric determination of analytes in their simultaneous presence using the Firordt method is shown. The developed approach is successfully applied to the analysis of polluted peat bog soil selected at a place of impact of the first step of a carrier rocket.

A study was made of the effect of synthesis conditions on the properties of a magnetoactive compound obtained by the interaction of iron(II) sulfate with potassium chromate. It was found that, in the formation of the magnetoactive compound, chromium is almost completely coprecipitates with the solid phase. To produce the magnetoactive compound with high relative magnetic susceptibility, it is necessary to precipitate it from the initial solution in no less than 10 min after its preparation at a K2CrO4: FeSO4 molar ratio of 0.16–0.18.

The nitration of sulfate lignin by nitric acid in an aqueous-dioxane medium under homogeneous conditions was studied. The method proposed makes it possible to synthesize nitrated lignin with the content of one nitro group per 1.5–2 phenylpropane units. At low consumptions of nitric acid, the nitration starts after an induction period, the duration of which decreases with increasing temperature. The presence of the induction period is related to redox transformations forming nitrous acid that nitrosates lignin.

The properties of the reaction products of hydrolytic lignin with nitric acid in water—dioxane medium were studied. The products are a mixture of nitrogen-containing oligomeric compounds with high degree of polydispersity.

Iron-lignosulfonate complexes are used as trace element fertilizers to control plant chlorosis caused by iron deficiency. In this study, iron-lignosulfonate complexes were synthesized by anodic dissolution of iron in solutions of sodium lignosulfonates or lignosulfonic acids. The resulting solutions of the iron-lignosulfonate complex do not contain extraneous ions that are present in similar preparations synthesized chemically from salts. Electrosynthesis of iron-lignosulfonate complexes was carried out with two iron electrodes with alternating polarity, changing the period of switching the polarity of the electrode, temperature and the duration of electrolysis. The anti-chlorosis action of the synthesized iron-lignosulfonate complex was tested while growing lupine on calcareous soil. The plants were treated with solutions of the synthesized complex by the non-root method after 10 and 20 days of their cultivation. For comparison, lupine was also grown on normal soil and on calcareous soil without iron-lignosulfonate complex treatment. The content of chlorophyll, the content of carotenoids and the mass of the ground part of the plants treated with the synthesized complex were the same or higher than those of the plants grown on normal soil. In addition, all these parameters were 2-3 times higher than that of the plants grown on calcareous soil without treatment.

The conditions of the synthesis of a magnetically active compound by redox transformation of iron(II) and chromium(VI) ions were determined. Under the synthesis conditions, the chromium compounds are recovered from the solution virtually completely. The use of technical-grade lignosulfonates in the step of the condensation of the magnetically active compound leads to considerable enhancement of the magnetic activity.

The nitration of phenol with excess nitric acid in aqueous dioxane, in contrast to the nitration in aqueous ethanol, yields exclusively 2,4-dintrophenol, whereas at equimolar ratio of phenol and nitric acid the major reaction products are mononitrophenols (99%), among which the p-isomer prevails.

Effect of a magnetic field and temperature on how the magnetic activity is formed in a synthesis of a nanosize magnetoactive compound is considered. Raising the temperature in the synthesis of the magnetoactive compound results in a substantial rise in the magnetic activity at the beginning of the synthesis and accelerates the sedimentation and peptization of the deposit. The magnetic field makes the magnetic activity approximately 30–50% higher and results in that a more compact deposit is formed, with the peptization rate not affected.

Photometric reaction of phenol nitrosation was studied. It was found that, depending on the reaction conditions, various products are formed, including dinitrophenol. The reaction kinetics is described by two consecutive reactions. The activation energies of the first and second stages are 63 and 163 kJ mol−1, respectively.

The effect of synthesis parameters on properties of a magnetoactive compound (MAC) prepared via condensation of iron(II) sulfate in the presence of sodium nitrite is investigated. It is found that nitrite ions almost completely coprecipitate with the solid phase during the formation of a magnetoactive compound and subsequently participate in the redox conversions to yield magnetite. In order to obtain a magnetoactive compound with high relative magnetic susceptibility, condensation from the initial solutions is to be carried out at least 15 min after it is prepared; sodium nitrite consumption is to be at least 0.12 mol/mol FeSO4.

New highly selective method is suggested for synthesis of 2,4-dinitrophenol by nitration of phenol with nitric acid in an aqueous-alcoholic medium at the boiling point of the reaction mixture. The yield of 2,4-dinitrophenol is as high as 80%.

A method for synthesis of a magnetoactive compound based on iron(II) sulfate in the presence of nitrosated lignosulfonates at temperature of 20 to 50°C is suggested. The method yields a magnetoactive compound with high relative magnetic susceptibility.

The influence of reagent consumption (sodium nitrite and nitric acid) and nitrosation time of lignosulfonic acids on their peptization activity during subsequent synthesis of a magnetoactive compound on the basis of iron(II) sulfate with the properties of a magnetic fluid was determined.

A precise sensitive spectrophotometric method was developed for determining formaldehyde in aqueous solutions. The possibility of joint determination of formaldehyde and formic acid was examined.

A precise spectrophotometric method was developed for determination of formic acid. The method surpasses in sensitivity the method based on proper UV absorption of formic acid.

The kinetics of lignosulfonic acid nitrosation in the presence of acetic and nitric acids used for generation of nitrous acid in combination with sodium nitrite was studied as applied to colorimetric determination of lignosulfonic acids.

A spectrophotometric method for determination of furfural and pentoses based on their color reaction with sulfuric acid in the presence of mercury(II) was developed.

The possibility of using the reaction of nitric acid with lignosulfonates for their quantitative determination in aqueous solutions was studied.