Annotation of the results obtained in 2016
Research area optimization has proved to be related to polypyrrole (PP) covering activated carbon (AC) that might make it possible to change the AC properties. Based on AG-3 AC and BAC produced industrially and modified by the current-conducting polypyrrole is the optimum alternative of the research area, the current-conducting polypyrrole ensuring biocompatible properties. Techniques have been developed electrochemical modification of carbon materials by pyrrole electropolymerization on their surface. By pyrrole electropolymerization on their surface with chloride and iodide ion as a dopant in water-organic mediums. Techniques have been developed for determining the open circuit potential (OCP). The procedure for determining the biocompatibility is developed. The biocompatibility of the modified AC was determined on basis of the traumatic effect for erythrocytes, i.e. the hemolysis. The procedure is developed for determining adsorption activity against endotoxins. The adsorption activity against endotoxins was determined in relation to bilirubin. The bilirubin concentration was determined by special medical technique. Such toxins as amitriptyline, triftazine, chlorineprothixine were used for studying the adsorption activity of the modified ACs. The determination and optimization of pyrrole electropolymerization are performed for carbon materials synthesized in potentiostatic and galvanostatic modes of operation in water chloride solutions, iodide ones and nonaqueous acetonitrile solutions. Parameters of the prepared electroconductive polymer depend on the electrosynthesis mode and the solution properties. It is found that more of the surface area was covered by the polymer in modifying by chloride and iodide solutions AG-3 AC than BAC AC. Modified AG-3 ACs happened to be the most suitable ones in terms of рН because their рН is close to the physiologic data range, 7.35 – 7.40. It is found that, absence of the significant differences between properties of modified ACs dependently on the electrochemical modification mode. Preparing modified AC samples to carry out in the potentiostatic mode because of using potentiostat made it possible to determine the electrochemical parameters of the pyrrole electropolymerization with higher precision. As it has been mentioned above the carbon hemocompatibility zone is within the range of OCP values from -150 to 50 mV. On this basis such ACs as AG-3/PP (Cl-), BAC/PP (I-), AG-3/PP (I-), AG-3/PP (Cl-)* were chosen for the further investigation. The study of adsorption efficiency for natural endotoxins as the function of the sorbate nature and modification conditions was carried out by the example of bilirubin. The AC samples were cleaned by the buffer solution before carrying out the investigations in order to make the рН value get closest to the physiological one. The high bilirubin content patient’s blood was used as the research subject matter, the bilirubin content being 220 µmol /l. The modified AG-3/PP (Cl-) AC appeared to be the most effective, it adsorbing about 55% of bilirubin. The iodide modification did not result in increasing the adsorption efficiency significantly, it totally increasing by 3-5%. It should be mentioned particularly that the AC modification in the nonaqueous solution resulted in decreasing the efficiency by 4%. The biocompatibility research is carried out for modified carbon materials, their adsorption properties being investigated against toxins. The biocompatibility investigation is one of the most basic ones determining the sorbate efficiency for using in medicine because the contact with patient’s blood is supposed to take place and the excessive sorbate traumatic effect may cause undesirable consequences. It is found that, AC adsorption activity against toxins investigated is in the range of 6 – 51 % for all modified ACs studied. AG-3/PP (Cl-) and AG-3/ PP (I-) demonstrate the best amitriptyline adsorption efficiency, 0.7 and 0.5 mg/g respectively. The modified AG-3/PP (Cl-)* showed the lowest activity against amitriptyline 0.35 mg/g, it being twice lower than for the AG-3/PP (Cl-) case. All modified ACs showed relatively low results against triftazine. AG-3/PP (Cl-) sorbed 0.007 mg/g showing the highest efficiency. ACs modified in iodide solution sorbed 0.002 mg/g being least effective. All modified ACs showed proper results against chlorprothixene in investigating adsorption efficiency. Modified AG-3/PP (Cl-) and AG-3/ PP (I-) ACs showed the best adsorption results, they sorbing respective 1.12 mg/g and 0.94 mg/g of chlorprothixene. Modified BAC/ PP (I-) and AG-3/PP (Cl-)* ACs sorbed 30% less. The laboratory technological regulations are developed for carbon material electrochemical modification in galvanostatic and potentiostatic modes in the flow-type electrochemical cell by using various inorganic and water-organic solutions. The laboratory technological regulations are developed for investigating samples of modified carbon materials including determination of the open circuit potential, determining the biocompatibility in terms of traumatic effect on erythrocytes, i.e. hemodialysis, the adsorption activity against endotoxins and exotoxins, the spectrophotometric method λ = 200 – 600 nm. Experimental studies are carried out for extracting exotoxins by examples of some psychoactive drugs used in clinics in treating acute exogenous poisonings. The AC adsorption activity did not drop more than by 20 % in comparison with the adsorption activity in model water solutions, it dropping by 18 % for AG-3/PP (Cl-) and by 19 % for AG-3/ PP (I-). By and large the adsorption efficiency was kept at the acceptable quality level. In triftazine case shows the lowering of adsorption activity by about 30 % in comparison with water solutions in using modified ACs, the AC modified by polypyrrole with chloride ion as a dopant happening to be more effective in comparison with the AC modified by polypyrrole with iodide ion as a dopant just like in model solution case. In studying the adsorption activity against chlorprothixene the lowering of adsorption activity against chlorprothixene was found to be about 15%. As a result of it both AG-3/PP (Cl-) AC and AG-3/ PP (I-) AC sorbates gave respective 0.94 mg/g and 0.80 mg/g. The study of metal oxide and nanocarbon materials, electrodes has been carried out in order to control the medium oxidation-reduction potential. Results of studying the repeatability in measuring ORTA electrode OCP after preprocessing showed that the mean value of OCP was 374 ± 6.0 mV, that being quite good parameter but worse than 374 ± 3 mV of the platinum electrode. The use of disposable metal oxide electrodes instead of platinum ones has proved to be promising because the platinum electrodes are used many times and they need to be sterilized for reusing.

 

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Annotation of the results obtained in 2014
The abnormal high capacity of the electrochemical supercondenser can be up to 250 farad per gram of the active substance due to two factors: - extremely small distance between electrical plates of the supercondenser, depending on theelectrolyte concentration and the size of ions; - maximum possible contacting area between materials that is obtained by using thenanostructured porous material immersed in electrically conducting liquid. As a result of the stage realization (2014) thepatent research and the scientific and technical literature revieware carried out in the followingfields: - nanostructured carbon materials; - the ionic liquids; - supercondensers (energy storage system), 602 literary sources of the most important Russian and foreign scientific literature including more than 70 patents having been analyzed. CARBONNANOFIBERS KEY SPECIFICATIONS - Specific surface:50 - 100 m2/g - Specific resistance: 0.06-0.08 ohm•cm - Weight by volume: 0.15-0.25 g/cm3 - Chemical composition: С> 85%, О 1-6%, Cl < 1%, Fe <10% - Ash content: less than 5% CARBON NANOTUBES KEYSPECIFICATIONS - Specific surface: 250 - 1500 m2/g - Specific resistance: 0.04-0.06 ohm•cm - Weight by volume: 0.12-0.2 g/cm3 - Chemical composition: С> 90%, О 1-6%, Cl < 1%, Со< 5%, Mo < 1% - Ash content: less than0.5% CARBONNANOFLAKES KEYSPECIFICATIONS - Specific surface: >1800 m2/g - Specific resistance: 0.04-0.06 ohm•cm - Weight by volume: 0.12-0.2 g/cm3 - Chemical composition: С> 95%, О 1-5%, Cl < 0,5% - Ash content: less than0.5% SINTEREDCARBONNANOMATERIALS KEYSPECIFICATIONS - Specificsurface: 1000-1800 m2/g (dependingon conditions ofpreparing the initial material) - Specific resistance: 0.04-0.40 ohm•cm - Apparentspecific weight: 0.40-0.7 g/cm3 - Chemical composition: С> 98%, О< 2% - Ash content: less than 0.5% OXIDIZEDCARBONNANOMATERIALS KEYSPECIFICATIONS - Specificsurface: less than 100 m2/g - Weight by volume: 0.12-0.2 g/cm3 - Oxygencontent: morethan 15% - Significantcontentof differentoxygen-containing groupson the surface. Studies of carbon nanomaterial sorptioncharacteristicsin relation to non-ferrous metal ions and rare-earth element ions have been carried out. The basic mechanisms of thecerium (III) ion sorption and lanthanum (III) ion sorption are determinedforfunctionalized carbon nanotubes (f-CNT) and graphene oxides (GO). The cerium ion adsorption values getstationary onesin 10 - 15 minutes, the sorption value being 180 - 200 mg/l for CNT and 260 mg/g for GO at рН = 2, cerium concentration 200 mg/g and the temperature 260С. Whencerium ion concentration increases from 5 up to 250 mg/l the adsorption value increases from 10 mg/g up to 200 mg/g. Therelationshipcharacteristics G = f (Cinitial) are identical for Ce3+ and La3+, the absolute values of G for La3+being 220 mg/gat Cinitial = 200 - 250 mg/l. Studies on non-ferrous metal ion separation (Ni2+, Cu2+, Zn2+) based on CNP adsorption in the range of рН = 4 – 6 have been carried out, the hydroxide formation not occurring. It has been stated that stationary adsorption values are less than 20 minutes in intensive stirring. The conditions beingрН= 6.0 СМе2+ = 20 mg/l,backgroundelectrolyte1 g/lNa2SO4.The efficiency of metal extraction can be estimated by the extraction extent i.e. α = ((Сin. - Сfin.) / Сin.) * 100 %. The concentration was determined by using inductivebound plasma mass spectrometer(IBPMS), XSeriesII Thermo Scientific Inc.It was stated that the extractionefficiencyincreased when the solution рН value increased, at рН = 10 hydroxide formation being 93% - 98% for systems 1 – 5. When CNM is present the extraction extent goes up 5 - 6%.CNM (graphene) sorption was studied with zirconium ions influenced by externalpolarization of 0.4 – 1.5 V as an example of the sorption, the adsorbent values concentrations being35 mg/g - 50 mg/g. The values go up to stationary ones in 60 minutes. The sizes of the particles for different kinds of CNP - surfactant (SAS)suspensions were determined by applying laser particle size meterNanotrac Ultra 253 with remoteprobeMicrotrac Inc., USA, the sizes of the particles being 228 nm for surfactant Triton X-100, 120 nm for anionic - sodium dodecyl sulfate(NaDDS, lauril-sulfate)surfactant, 190 nm for cationic – septum (dimethylammonium chloride) surfactant. 16 model electrochemical devices have been developed, made and tested. The analysis has shown that the design of electrochemical system, the nature of electrode materials and an ionic liquid are significant and allow determining theway of making electrochemical devices based on functionalized carbon nanomaterials with the enhanced power characteristics. Scientifically-methodical bases and product design and production engineeringways have been developed for making electrochemical devices based on functionalized carbon nanomaterials and nanocomposites with enhanced power and energy characteristics and low cost foreffective electric power accumulationin electromobiles and other types ofelectric traction transport, as well as in the distributed power engineering, including the use of renewable energyas a result of carrying out the stage (2014) ; the work has been carried outcompletelyin corpore.

 

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Annotation of the results obtained in 2015
As a result of the stage realization (2015) the patent research and the scientific and technical literature review have been carried out in the following areas: - engineering procedures of electroflotation membrane concentration, extraction of trace rare metals and nonferrous materials (140 sources); - neutralization of anthropogenic liquid wastes with nonferrous materials (131 sources); - insoluble metal oxide anode materials (113 sources). The research work has been carried out for increasing efficiency of the electroflotation membrane concentration and extraction of trace rare metals and nonferrous materials from model systems under the steady-state condition. Optimal conditions have been determined for electroflotation extraction of some nonstable valence metals Fe(II)/Fe(III), Ni(II)/Ni(III), Co(II)/Co(III), Ce(III)/Ce(IV) in neutral solutions NaCl, Na2SO4, NaNO3 (pH = 5 – 7). The electroflotation extraction of sparingly soluble cerium compounds (III, IV) and its dependence on the solution pH have been studied. The electroflotation process for extracting sparingly soluble cerium compounds (III) has been proved to carry out most completely and effectively within the range of рН 7 – 8, it being within the range of рН 6 – 7 for extracting sparingly soluble cerium compounds (IV), the extraction scale getting up to 96 – 97%. We have established the influence of anionic flocculants, cationic ones as well as nonionic flocculants on the efficiency of the electroflotation extraction of sparingly soluble cerium compounds. The limit scale of extraction of sparingly soluble cerium compounds (III, IV) has proved to be observed in adding cationic flocculant С-496, operating range expansion taking place for concentrations 0.2 – 1.0 g/l (Се(III)), 0.2 – 1.5 g/l (Ce(IV)). Testing new reagent-compositions of surface-active substance (surfactant) – carbon nanomaterial has been carried out for intensifying and increasing efficiency of the electrochemical process for extracting sparingly soluble rare metal compounds and nonferrous materials. Hydrodynamic radius (R) and electrokinetic potential (ζ) of CNM particles have been determined in the presence of surfactants of different kind. The sizes of particles (Ø, micrometers) have proved to range from 10 – 17 micrometers for Fe, 8-9 micrometers for Ni, and 12 -15 micrometers for Co. It has been found that the particle size is 12 µm in the range of рН 6 – 10 for Ce(OH)3, the Ce(OH)4 particle size being 20 µm with 1 g/l salt cake solution. Се(ОН)3 particles change their charge from positive (рН 5-7) into negative one (рН 8-10) in the range of рН 6-10. The isoelectric point is observed at рН 7.5±0.1. The electrokinetic potential in the range of рН 6-10 is constant being -16 µV and respectively. Isoelectric points (рН0) of carbon nanotubes (CNT) and carbon nanoflakes (CNF) have been determined according to the ways for getting materials in inactive electrolytes NaNO3, NaCl. The рН0 value varies from 5.5 to 7.0 depending on the getting conditions. The NC-surfactant suspension influence has been illustrated by the lanthanum hydroxide electroflotation. It has been found that the electrolyte nature influences the extraction scale of the hydroxide La(III). The maximum extraction scale takes place in NaCl solutions being 56%, the minimum one occurring in sodium carbonate - 13%. Cation surfactant Septapav influences the process efficiency positively increasing the extraction scale up to 96 - 98% in such electrolytes as sodium sulphate, sodium chloride, sodium nitrate and up to 45% in carbonate nitrate. High process efficiency has been found in the presence of CNF–Cation surfactant suspension with sodium carbonate, it being 95% (13% without additives). The examination shows that the process efficiency increases from 10 – 13 % up to 95% mostly for the Na2CO3 system in the presence of NC–Cation surfactant suspension additive. The positive effect occurs in the NaCl electrolyte as well, the electroflotation process efficiency increasing from 50 – 55 % up to 95 – 97 %. The influence of new NC + Surfactant reagents has been studied for multicomponent system containing around 10 rare-earth elements. The positive influence of the NC + Anion Surfactant additive on the selective extraction of some metals, - yttrium, zirconium, cerium, scandium, - was found in рН 2 – 4. The surfactants, nanocarbon materials have been found to influence the selective extraction of some rare-earth element - Zr – NSAS, Y + CSAS – NC. The NC-Surfactant suspension influence has been illustrated by the lanthanum hydroxide electroflotation. It is found that the electrolyte nature influences the extraction scale of the hydroxide La(III). The maximum extraction scale takes place in NaCl solutions being 56%, the minimum one occurring in sodium carbonate - 13%. Cation surfactant Ceptapav influences the process efficiency positively increasing the extraction scale up to 96 - 98% in such electrolytes as sodium sulphate, sodium chloride, sodium nitrate and up to 45% in carbonate nitrate. High process efficiency has been found in the presence of CNF–Cation surfactant suspension with sodium carbonate, it being 95% (13% without additives). The adsorptivity of nanocarbon materials of different kind has been found for a number of nonferrous materials, - Cu, Ni, Zn, - and rare-earth elements - Се, La, Nd. The research work has been carried out for evaluating efficiency of electroflotation membrane (EFM) process for extracting trace rare metals and nonferrous materials from liquid anthropogenic wastes under flowing conditions, the process kinetics being described for electroflotation apparatus of both cyclic and noncyclic (flow-type double-chamber electroflotator) operations. The relationships of the flotation chambers w1 and w2 have been established at given specific output Q and flotation process time, optimal conditions of the current load (I1 и I2) being established for both chamber 1 and chamber 2. The optimal relationships are I1: I2 = 1: (0.1 – 0.3); w1: w2 = 1: (3 – 5), power inputs being 0.8-1.2 kW/m3. The optimal conditions for flowing condition electroflotation extraction of nonferrous materials have been found to be 98 – 99 % extraction scale, electroflotation time being less than 5 min in the presence of around 5 mg/l flocculant/ surfactant. Electrolyte pH is 9 – 10.5. The optimal parameters of electroflotation extraction and separation for rare-earth elements La3+, Ce4+, Ce3+, Sc, Y depend on the electrolyte composition, the extraction degree being 98 – 99 %, the concentration range – to 1000 mg/l; the optimal values of рН for solutions containing Се (IV) pH 4 – 5, La (III) pH 8 – 10, Се (III) pH 7 – 9, Sc рН 7, Y pH 8 – 10. The possibility of electro-oxidation of cerium (III) ions from productional solution has occurred with 65% current efficiency, and 100% oxidation scale of cerium (III) ions. Preliminary calculation has been done for electrolysis unit for cerium (III) ion electro-oxidation with 5 kg/h efficiency. The optimal conditions for flowing condition electroflotation extraction (separation) of nonferrous materials (Cu, Ni, Zn, Co, Се) have been found to be 98 – 99 % extraction scale, electroflotation time being less than 5 min in the presence of around 5 mg/l flocculant/ surfactant. Electrolyte pH is 9 – 10.5. New patterns of relationship have been established in electroflotation extracting sparingly soluble scandium compounds in electrolytes like sodium sulphate, sodium chlorides, sodium nitrate and sodium carbonate. The process is most effective at рН = 7-8, the extraction scale being 97 - 99%. The time process is less than 5 minutes. The sodium carbonate electrolyte inhibits EF extraction, the extraction scale being less than 50 -55%. The time process is 25 - 30 minutes. The process efficiency increases up to 90 - 95% in the presence of 1 mg/l NaDDS surface-active substance in the carbonate electrolyte, the electroflotation time being less than 5 minutes. The 70-80% EF efficiency increase occurs in adding cation surfactant (septapav) into carbonate electrolyte. The NC-Surfactant suspension influence has been illustrated by the lanthanum hydroxide electroflotation. It is found that the electrolyte nature influences the extraction scale of the hydroxide La(III). The maximum extraction scale takes place in NaCl solutions being 56%, the minimum one occurring in sodium carbonate - 13%. Cation surfactant Ceptapav influences the process efficiency positively increasing the extraction scale up to 96 - 98% in such electrolytes as sodium sulphate, sodium chloride, sodium nitrate and up to 45% in carbonate nitrate. High process efficiency has been found in the presence of CNF–Cation surfactant suspension with sodium carbonate, it being 95% (13% without additives). The research work has been carried out on establishing efficiency and selectivity of EFM concentration and extraction of trace rare metals and nonferrous materials from multicomponent mixtures. The research work has been carried out on studying pH influence on the scale of extraction of rare-earth elements contained in 10 component system with Fe, Cu, Y, Zr, Се, Nd, Th, La and other metals. It has been demonstrated that no one component can be extracted at рН = 2. At рН = 3 the extraction scale is Zr - 8%, Nd - 10%, La - 9%; at рН – 4 Сu2+ - 8%, Fe - 7%, Y - 24%, Zr - 30%, Ce - 38 %, Nd - 33%, Th - 31%, La - 32%; at рН - 5 - 20 % Cu, 90% Fe, 64% - Y, 72% Zr, 80% Ce, Nd - 68%, 93% - Th, 73% - La; at рН - 6 - Сu - 24%, Fe -99%, Y - 80%, Zr – 0 (there is no Zr in the solution), Се - 90%, Nd – 0 (there is no Nd in the solution), Th - 99%, La - 90%. All metals mentioned above can be extracted as a mixture, the efficiency being 90 - 99% and the selective separation is quite complicated. The electrolyte and surfactant nature influences the process selectivity. The acidic pH range (2-6) has been determined as the most effective for the selective electroflotation separation and extraction of metals. The process of the selective electroflotation separation of some ion metals such as Cu2+ Ce3+, Cu2+ Ce4+, La3+ Ce3+, La3+ Ce4+, Fe2+ Ce3+, Fe2+ Ce4+, Fe3+ Ce3+, Fe3+ Ce4+ has been examined in the range of рН 2 – 10. The separation factors have been determined to be: K (Ce3+ /Cu2+) = 34 at pH = 7; K (Ce4+ /Cu2+) = 66 at pH = 5; K (Ce4+ /Fe2+) = 5 at рН = 5, K (Ce3+ /Fe2+) = 7 at рН = 4, K (Ce3+ /Fe3+) = 6 at рН = 6; K (Ce3+ /La3+) = 2 at рН = 6 (in the presence of NO3-); K (Ce4+ /La3+) = 15 at рН = 5 (in the presence of Сl-). The requirements specification on creating engineering technical documents has been worked out for operative embodiments of the plant for electroflotation membrane concentration and extraction of trace rare metals, nonferrous and scattered elements from liquid anthropogenic wastes. The monograph has been published, two patents have been applied, three know-hows have been formalized, a Doctor of Science and PhD dissertations have been defended. The stage work for 2015 has been done in full.

 

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