Purification Of Industrial Wastewater Research Articles

Знесірчення промислових сульфідно-лужних розчинів сумішевими сорбентами

Modern methods of purification of hydrocarbons (oil, gas) from sulfur-containing compounds (H2S, RSH, RSSR, naphthenic acids, NaHS, Na2S) have been analyzed, which are based on their alkaline extraction followed by oxidation of air oxygen on homogeneous or heterogeneous catalysts. Despite the promising process of catalytic oxidation of sulfur-containing compounds in technical solutions, it has a number of significant drawbacks, primarily related to the activity of the catalyst and the ability to form a large number of intermediate products of the oxidation. Other known methods for the removal of sulfur-containing compounds from technical solutions are based on the chemical interaction of sulfide alkaline solutions with aqueous solutions of metal salts of III-V analytical groups or their interaction with elemental sulfur to form the corresponding sodium polysulfides. A number of studies have investigated the sorptive extraction of sulfur-containing compounds from technical aqueous solutions or commercial hydrocarbons/diesel fuels using various modifications of activated charcoal, natural sorbents, polymeric organic absorbers or mixed sorbents. However, despite the wide variety of sorptive materials studied, the problem of purification of industrial wastewater from sulfur-containing compounds is not completely solved and, in turn, depends on the chemical structure of the surface of the sorbent, as well as on the objects of purification, pH of media and several other factors. It has been developed an alternative method of purification of aqueous sulfide alkaline solutions/wastewater from sulfide and hydrosulfide ions by their adsorption on pre-regenerated mixed sorbents consisting of activated charcoal (AC) of brand Decolar A and kieselguhr (K) of brands Becogur 200 and Becogur 3500 with mass ratio of 4 : 6. It has been found that the degree of purification of the investigated solutions, which is strongly dependent on the initial concentrations of sulfide and hydrosulfide ions, is 95,7…96,6 % and indicates the high efficiency and possibility of using such technologies in industrial production. Surface study of mixed sorbents (AC+K) after purification of aqueous solutions was performed using X-ray phase analysis. The received data confirms the amorphous composition of the activated charcoal and the presence of the main SiO2 cristobalite, 4,02, on the left side of the diffractogram, as well as a number of peaks of various Na2S modifications.

SUBSTANTIATION OF OPTIMAL CONDITIONS FOR THE REAGENT PURIFICATION OF WASH WATER FROM HEAVY NON-FERROUS METAL IONS

The article is devoted to the analysis of reagent methods, selection of reagents and optimal doses for the process of carrying out the purification of industrial wastewater from heavy non-ferrous metal ions, such as copper ammonium, copper sulfate, nickel, hexavalent chromium. Presents data on the cost of each reagent used, as well as a table with the original data. The course of the experimental work, the pH value, the initial metal concentration and the dose of the reagents used are described. The graphic results of experimental work on the purification of wash water containing various non-ferrous metals are given, which show the final concentrations of metals and the cost of cleaning 1 cub m of runoff. As a result of the analysis, conclusions were made about the effectiveness of the various reagents used on heavy non-ferrous metal ions. The criterion for the efficiency of cleaning the wash water was the possibility of achieving the maximum permissible concentration for discharge into the fishery reservoir, the permissible concentration for discharge into the centralized water disposal system of the city and standards for permissible discharge for the enterprise. The optimal conditions for reagent purification of wash water are found, taking into account the possibility of achieving each considered criterion of purification efficiency, with the minimum cost of reagents. The use of reagent purification of wash water requires subsequent neutralization of treated wastewater. The choice of the technological scheme of purification of wash water from heavy non-ferrous metal ions will be determined, on the one hand, from the heavy non-ferrous metal ion contained in the wastewater, and on the other hand, from the need to achieve the required cleaning criterion.

Combined enhancement effects of static magnetic field (SMF) and a yeast Candida tropicalis SYF‐1 on continuous treatment of Acid Red B by activated sludge under hypersaline conditions

AbstractBACKGROUNDLarge amounts of wastewater containing azo dyes and salts (e.g. from textile and dyeing processes) are produced each year, which need appropriate treatment before discharge. In the present study, combined enhancement effects of static magnetic field (SMF) and a halotolerant yeast Candida tropicalis SYF‐1 on continuous treatment of Acid Red B (ARB) under hypersaline conditions (containing 30 g L−1 NaCl) were estimated in a sequencing batch reactor (SBR). The dynamics of the microbial community was also analyzed.RESULTSRemoval percentages of ARB concentration, chemical oxygen demand (COD) and acute toxicity in the yeast–SMF co‐enhanced SBR (named as MSF‐SBR) were finally stabilized at about 98.0, 98.2 and 72.9% respectively, which were the highest among all SBRs. MSF‐SBR also possessed the highest biomass concentration (∼7462.1 mg L−1) and the best sludge settleability. Higher activities of nicotinamide adenine dinucleotide‐dependent dichlorophenol indophenol (NADH‐DCIP) reductase, lignin peroxidase (LiP) and manganese peroxidase (MnP) in MSF‐SBR were determined as responsible for higher degradation and detoxification efficiency. Bacterial genus Defluviimonas was putatively enriched in MSF‐SBR, which might be responsible for detoxification of aromatic intermediates. Candida was identified as the most dominant fungal genus in MSF‐SBR with a total relative abundance of 8.15%, which was responsible for effective dye degradation and detoxification.CONCLUSIONMSF‐SBR displayed higher and more stable treatment efficiency of ARB under hypersaline and continuous operation conditions. This study may provide a potentially applicable method for coping with purification of hypersaline industrial wastewaters. © 2019 Society of Chemical Industry

A combination machine for industrial wastewater purification

The statistic information about the amount of discharge of pollutants into water sources in Russia is studied. Also, the main problems of wastewater purification are discussed. According to the literature survey, the perspective directions in wastewater purification, as a result of the manufacturing activity of the food industry enterprise, are brought out here. It is offered to choose an electrochemical treatment as a basic stage of wastewater purification. And finally they offered to use a sorption final treatment. A machine called an electrolyzer-adsorber which was made by the authors is presented and described. The main technological parameters, which influences on the level and power-intensity of the electrochemical sorption purification happening in the machine are listed. The results of the experimental researches in choosing the optimum parameters in the wastewater purification machine called the electrolyzer- adsorber were studied at the one of the Volgograd food industry enterprise.

TECHNOLOGY FOR WATER PURIFICATION FROM RESIDUES OF DRUGS AND PLASTIC

Purpose. The main purpose of the article is to develop a technology for water purification from residues of oil-fat containing drug (medicinal) cream, in particular technology and a technological scheme for purifying urban (municipal) wastewater from plastics and residues of drugs. Methodology. The studies were carried out based on the analysis of scientific sources and reporting data on the availability of drugs and plastics in the water of Ukraine, European countries, and the USA. Findings. The authors present the results of a comprehensive review of issues related to the determination of the availability of drugs in various waters, their concentrations and the most dangerous drugs-toxicants. Medicines and plastics can accumulate not only in humans and animals, but also in sea and river fish, etc. The presence of drugs and plastic in the body can have a negative impact on the health. The treatment facilities in Ukraine and the world are not sufficiently adapted for the detection of drugs and plastics and their purification. Originality. The authors of this material conducted studies to determine the content of plastic in drinking tap water in Dnipro and Zaporizhzhia cities. Drinking water from the tap contains less plastic particles than bottled water of the famous Ukrainian trade brands. The work developed technological schemes for the purification of industrial wastewater from pharmaceutical enterprises for the manufacture of creams, ointments, oils and other products for treatment and cosmetic purposes. Structures and methods for purifying water from these pollutants have been proposed, which had not been previously used at water purification stations, but successfully apply in other industries. Practical value. The use of environmentally efficient technologies in Ukraine will allow obtaining high-quality drinking water, but it will require re-equipment and reconstruction of water treatment plants. Major funding should be provided by corresponding articles. Currently, in Ukraine (even in Kyiv) there are no stations for the purification of drinking and waste waters, which would use modern technologies and facilities, but high-quality water is the health and life of people.

Enhanced flocculation activity of polyacrylamide‐based flocculant for purification of industrial wastewater

The flocculation activity of commercially available anionic poly (acrylamide‐co‐acrylic acid), p (AAm‐co‐AA) has been significantly improved, without any inorganic coagulant aid. The effect of three types of surfactants, anionic sodium lauryl ether sulfate (SLES) (Palm Epimen), nonionic cocamide DEA, zwitterionic amphoteric Amphotensid B5, and one organic cation, trimethylammonium bromide (TAB) on coagulation/flocculation performance have been investigated. The performance has been analysed in terms of turbidity, total suspended solid (TSS), total iron (TI) content, and BTEX for treating two kinds of industrial wastewater, produced water (PW) and starch water. We have shown that adding a small amount of each of the studied surfactants, and especially cationic TAB, significantly increases the coagulation/flocculation performance without modifying pH levels. A combination of low dosage of flocculant (310 ppb) and TAB (310 ppb), after 5 minutes, presented 88%, 81%, and 62% reduction in turbidity, TSS, and TI content, respectively, whereas by using 5 ppm of flocculant alone (16 times more), only 76%, 75%, and 43% removal was obtained. The results reveal that TAB performs as an efficient coagulant booster. Compared with regular inorganic coagulants, it is more cost‐effective, reduces the consumption of treatment chemicals, and the pH‐dependency of contaminants removal.

Role of pulping process as synergistic treatment on performance of agro-based activated carbons.

To recommend the beneficial effect of the pulping process on enhancing agro-wastes as precursors for the production of high-performance activated carbons (ACs), different pulping methods (alkali, sulfite and neutral sulfite) were applied on two available Egyptian agriculture by-products (rice straw and sugar cane bagasse), using the one-step pyrolysis method and H3PO4 activating agent. The adsorption performance of the different prepared ACs was evaluated in terms of Iodine Numbers and their sorption properties for removing the methylene blue (MB) from aqueous solutions. The corresponding sorption processes were also analysed using Lagergren first order, pseudo-second order and intraparticle diffusion models. Data revealed that the applied pulping conditions were effective for removing the non-cellulosic constituents of agro-residues. This was demonstrated by the hydrogen/carbon and oxygen/carbon ratios, thermal stability and IR-measurements of the final pulps. These data were effective on the particular sorption properties of RS and SCB-based ACs. Interestingly, the pulping process is a profound modification of the SCB-based fibres, on which it induced a clear increase of the specific surface areas of the corresponding ACs even though they had an impact on the sorption of MB and iodine. These values are superior to the reported data on agro-based ACs with H3PO4 activators. Pulping processes therefore play a dual role in the sorption properties of ACs. The first important role is the impact on the specific surface areas and the second impact is a profound modification of the surface chemistry of the ACs. Therefore, SCB-based ACs can be seen as an economical breakthrough product, and an alternative to the high-cost commercial ACs for the purification of industrial wastewaters.

Synergistic effect of band edge potentials on BiFeO3/V2O5 composite: Enhanced photo catalytic activity

The BiFeO3/V2O5 has been successfully synthesized by simple annealing of BiFeO3 nanoplates and V2O5 nanoflower. The phase, structural, optical properties and chemical state of the BiFeO3, V2O5 and different composition of BiFeO3/V2O5 samples were comparatively characterized by various spectroscopic and microscopic techniques. The prepared catalyst exhibits unique photo catalytic and post-oxidation/reduction ability for removal of various (MB, Phenol, CV, RhB) water organic pollutants. Compared to pure BiFeO3 and V2O5, the different Wt % of BiFeO3/V2O5 composition exhibited higher photo catalytic activity. The fortunate BiFeO3/V2O5 interface hybrid photo catalyst makes a significant impact in the enhancement of photo catalytic reaction. This remarkable efficiency could be ascribed to the synergistic effect between the V2O5 petals and BiFeO3 plates. The exceptional morphology, increased surface area, uniformity, less-agglomerated spreading could increase the ability of visible light response, which lead the improved electron transport ability and the higher charge separation. The enhanced rate of photo generated charge carriers separations were evinced by the EIS and PL spectrum measurements. The allowed radical trapping experiment divulge that the hole (h+), and super oxide radical (O2-) are the minimized effect in degradation, on the other hand hydroxyl radical (OH) is plays the foremost role and act as the active radicals in the catalytic organism. In relations of above investigation, a probable photo degradation mechanism of the as-synthesized photo catalyst is carefully explicated. This effort delivers an effective approach to design and fabricate the efficient photo catalyst through integrating of materials, which has a potential for industrial waste water purification.

SORPTION PROPERTIES OF METALLURGICAL SLAGS

Problem. The modern effective way of sewage treatment is sorption technology. The advantages of the sorption process are: high efficiency, the ability to clean multicomponent sewage, ensuring the stability of the absorption capacity of the sorbent and the possibility of its regeneration, ensuring the technology cycle. The economic efficiency of the sorption purification of industrial waste water from pollutants of inorganic and organic origin increases when natural compounds, cheap materials, by-products and waste products are used as sorbents. An urgent problem of integrated use and complete utilization of industrial waste is solved simultaneously. Goal. In order to substantiate the fundamental possibility of use as a sorbent of metallurgical slag for the FeNi alloy production of the Pobuzhsky Ferronickel Plant (PFP), mineral, elemental, and radionuclide composition of slag was conducted. Metho­dology. The methods of the study were X-ray diffraction, gamma-spectrometry, spectrophotometric analysis and electron-probe microanalysis. Results. The absence of toxic elements in metallurgical slag of PFP, the presence of calcium and magnesium aluminosilicates (mineral diopside), the presence of amorphous substances, compliance with the requirements of radiation safety standards (Class I of radiation hazard), and stability in the liquid phase are shown. The sorption activity of slag in relation to organic compounds on the basis of methylene blue dye (MB) was studied. The optimal conditions for the activation of slag are determined: the active agent is a solution of 0.5 M H2SO4; temperature 20 oC. The amount of adsorption of slag in 10 days reaches a maximum of 0.194 mg/g, which corresponds to 96.9 % purification of the solution from the MB. Originality. The fundamental possibility of using PFP slag as a sorbent in relation to organic compounds due to the large surface area and the presence of an amorphous phase is determined. The practical absence of desorption of organic sorbate has been proved. Practical value. Slag of PFP can be used as an adsorbent in technological processes. The advantages of its practical use are solving environmental problems of industrial regions while reducing the volumes of slag dumps and saving water resources.

A Laboratory-based Experiment on the Efficacy of Graphitic Carbon Nitride Doped with Tungsten Chloride in the Purification of Industrial Wastewater through Degradation of Organic Dye Pollutant

Water is an essential commodity whose quantity and quality needs to be secured for easier accessibility at both the industrial, public and household levels. However, its availability in adequate quality and quantity has continued to decline worldwide. Indeed, rise in human population coupled with the climate change phenomena have greatly impacted on the quality of water resources through increased organic and inorganic pollution. Rhodamine B (RhB) dye is a common organic pollutant majorly in industrial wastewater and with numerous environmental and human health effects. The application of graphitic carbon nitride (G-C3N4) in the purification of industrial wastewater to enhance the removal of RhB is a technology of interest to most environmental quality regulators and agencies. The study was therefore aimed at investigating the performance of graphitic carbon nitride doped with tungsten chloride in the degradation of organic dye pollutant rhodamine B dye from industrial wastewater. The study showed that the as-prepared hybrid photo catalyst exhibits an improved photo degradation performance because of its synergetic effect. Indeed, the photo excited electrons from g-C3N4 were able to efficiently separate and are injected to the conductive band of WO3. The optimum photo activity occurred at the optimum ratio of 0.25WO3/g- C3N4. There was also stability and efficiency within the hybrid catalyst within the photo degradation process. Indeed, the composite indicates a high activity for degradation of RhB under visible light irradiation. The presence of g-C3N4 proved to be beneficial for enhancement in photo catalytic activity of the g-C3N4-WO3 composite and proved to be one of the best alternative modes of n the degrading organic dye pollutant Rhodamine B dye from wastewater.

Development of a technology for utilizing the electroplating wastes by applying a ferritization method to the alkaline­activated materials

The study reported in this paper reveals the effective way of recycling water treatment products by using them as a component of alkaline cements and concretes based on them. Large-scale utilization of products from waste water purification in the composition of building materials has traditionally been limited given that heavy metal compounds are included in the composition of waste. Materials that are created using such a waste are traditionally considered to be dangerous for human health and the environment. Application of alkaline cements as matrices for binding these wastes and related products makes it possible to solve the task on reliable binding of heavy metals. It was experimentally determined that the main crystalline phases are calcite, quartz, hematite, coesite, and diopside. Also defined is the presence of gelatinous neo formations that are capable of subsequent recrystallization into zeolite-like structures. Such a composition of neo formations provides the involvement of heavy metal ions into the structure of the received material. Compressive strength of alkaline-activated systems that employ water treatment products (industrial wastes of galvanic production) reaches 40 MPa in standard mortars. Application of the developed cements in concretes makes it possible to achieve the strength of 45 MPa without changing the technological process of concrete preparation. The leaching of heavy metals from the matrix of alkaline cements was studied following the aging of up to 28 days by using atomic absorption spectroscopy. The study performed has shown that the alkaline cement matrix is characterized by high immobilizing properties relative to the heavy metal compounds (the level of immobilization of heavy metals ions is up to 99 %) and allows the use of industrial waste water purification products in the composition of alkaline cements and concretes based on them. Application of such an approach will not only solve the environmental problems related to disposing of hazardous products from water treatment, but would also make it possible to obtain building materials for general purposes with high operational properties

Dye-Mediated Interactions in Chitosan-Based Polyelectrolyte/Organoclay Hybrids for Enhanced Adsorption of Industrial Dyes.

Noncovalent, dye-mediated interactions between organo-montmorillonites ("organoclays") and a chitosan-based polyelectrolyte are exploited for highly effective and fast removal of different, industrially important anionic dyes (single-azo, double-azo, and anthraquinone) from aqueous solutions. The addition of only 10 wt % of the polyelectrolyte to conventional organoclay results in a 100% increase in absolute dye uptake capacity, an acceleration of dye uptake kinetics by up to 500%, and the flocculation of large, easily separable sorbent aggregates. These substantial improvements in adsorption performance are driven by the mediating effect of the anionic dyes (acting as the electrostatic mediator between the positively charged polyelectrolyte chains and organoclays), enabling the formation of true hybrid sorbent structures without the need for covalent cross-linking chemistry. The dye-mediated sorption and hybrid formation mechanism is further evidenced by structural and chemical characterization of the hybrid sorbents (small-angle X-ray diffraction and IR mapping) as well as by analysis of dye sorption kinetics according to the intraparticle diffusion model. Importantly, the organoclay/polyelectrolyte hybrid system provides a highly interesting adsorbent for the treatment of dye mixtures. Our study shows that structurally different anionic dyes localize at different sites within the hybrid structure (organoclay intergallery spaces vs polyelectrolyte/organoclay interface), enabling the simultaneous adsorption of different dyes with high efficiency. Consequently, the total uptake capacity for dye mixtures was 50% larger than that of individual dyes, demonstrating the enormous potential of the hybrids for industrial wastewater purification, where dye mixtures are ubiquitous.

A Simple Method for Removal of Carbon Nanotubes from Wastewater Using Hypochlorite

Carbon nanotubes (CNTs) have been applied in a wide range of fields, such as materials, electronics, energy storages, and biomedicine. With the rapid increase in CNTs industrialization, more and more CNT-containing wastewater is being produced. Since concerns about the toxic effects of CNTs on human health persist, CNT-containing wastewater should not be released into the environment without purification, but no effective methods have been reported. In the present study, we report a simple method to eliminate CNTs from industrial or laboratorial wastewater using sodium hypochlorite. Direct treatment of aqueous dispersions with sodium hypochlorite solution completely degraded CNTs into carbon oxides or carbonates ions. Since hypochlorite is environmentally friendly and frequently used as a disinfectant or bleaching agent in domestic cleaning, this method is practical for purification of CNT-contaminated industrial wastewater.

Composite Sorbent Filter Material on the Basis of Man-Caused and Minerals

It is about problems in purification of industrial wastewater and utilization of solid wastes as raw materials resources which are needed a scientific way of studying. The way of generation composite granular sorbent filter material on the basis of man-caused and minerals, using which is allowed to increase ecological safety food industry enterprise because of using waste conversion technique, as well modern methods of sorption purification , is offered and described here. A detailed chemical composition, which consists of tobacco dust and natural component as bentonitic clay, using for getting granular sorbent filter material, is studied. They studied real industrial wastewater to make researches for the detection residual impurity in the filtrate using composite granular sorbent filter material.

An Experimental Study of Photocatalytic Degradation of Congo Red Using Polymer Nanocomposite Films

Eco-friendly polymer nanocomposite films were synthesized using biodegradable polymers of chitosan and polyvinyl alcohol as polymeric matrices and carbon black nanoparticles as the reinforcement. These films were applied to study their applicability to industrial wastewater purification as a photocatalyst for degradation of Congo red as a target pollutant and to study the effect of the polymeric matrix types of the films on their performance as a semiconductor photocatalyst. Fourier-transform infrared (FT-IR) spectra and X-ray diffraction (XRD) were used to characterize the films. Visible light photocatalytic degradation of Congo red as a pollutant under various operational conditions of pH, dye concentration, contact time, and light intensity was performed. Photocatalytic results revealed that the polymeric substrate type does not play a major role in the photodegradation of the dye, and the best operational conditions were at a pH of 6 and a dye solution concentration of 8 mg/L.

A new effective nano-adsorbent and antibacterial material of hydroxyapatite

In the present work, nano-particles of potassium-substituted hydroxyapatite with formula of (Ca2.94K2.06)(PO4)0.94(CO3)2.06(OH) (KHA) are reported showing effective adsorption of Congo red dye in the room temperature. Synthesized sol–gel-derived KHA was identified by XRD, FTIR, TGA/DTA, and EDXA analyses. Moreover, the size of nano-particles and micro-strain of the synthesized KHA were measured using Williamson–Hall (W–H) plots and TEM in amount of 65–70 nm. The capacity of equilibrium adsorption (qm) for 100 ppm of Congo red was evaluated as high as 505.19 mg g−1 under optimum conditions. The adsorption charts and kinetic results obtained at ambient conditions well fitted with the Langmuir equation and the pseudo–first–order model with correlation coefficients of 0.9939 and 0.9867, respectively. The obtained results obviously show that the new synthesized KHA can be used for industrial wastewater purification in a good manner. The title nano-material also shows excellent antibacterial activity as highly prevention of bacteria strain growth with the lowest concentration of 125 µg/mL.

Making the Most of Precious Metal Nanoparticles in the Purification of Industrial Wastewater by Catalytic Wet Air Oxidation

The aim of catalytic wet air oxidation is to use air to remove organic contaminants from wastewater through their complete oxidation, without having to vaporise the water. To date, the widespread exploitation of this process has been held back by the low activity of available catalysts, which means that it has to be operated at above-atmospheric pressure in order to keep the water in the liquid phase at the elevated temperatures required to achieve complete oxidation. Here we present an overview of an ongoing study examining the key requirements of both the active phase and the support material in precious metal catalysts for wet air oxidation, using phenol as the model contaminant. The major outcome to date is that the results reveal a synergy between platinum and hydrophobic support materials, which is not apparent when the active phase is ruthenium.

Optimization of nitrogen and phosphorus removal from saline wastewater using Halomonas sp. H12 strain

Efficient simultaneous nitrogen removal and phosphorus accumulation microorganisms are great significance for the purification treatment of high salt wastewaters containing N and P. In this paper, the processes of nitrogen removal and phosphorus accumulation of Halomonas sp. H12 strain under high salt conditions were investigated. The optimal conditions of nitrogen removal and phosphorus accumulation were examined separately by using response surface methodology. The results showed that the Halomonas sp. H12 strain had high efficiency competent of nitrogen removal and phosphorus accumulation under high salt conditions under both growth stage and non-growth stage. Within 108 h, the rates of the nitrogen removal and phosphorus accumulation reached 78.51% and 49.18% respectively. During 0-84 h, the strain was in the growth stage, and its nitrogen removal rate and phosphorus accumulating rate increased gradually. At 84-108 h, the strain then entered the non-growth stage with its growth reached the maximum. Interestingly in this equilibrium phase, high efficient nitrogen removal and phosphorus accumulation were still carried out with the prolongation of time. Results from this work are of great significance for the purification of industrial wastewaters containing N, P and high salt.

Thermodynamic prognosis of the efficiency of toxic metals extraction from solution by microorganisms and their genetic potential

Aim. Thermodynamic justification of pathways of microbial interaction with metals and development of theoretical foundations of novel biotechnologies for purification of industrial waste water from environmentally hazardous metals-oxidizers (CrО42-, MoО42-, WО42-). Methods. The fields of stability of metal compounds in aqueous solutions in the coordinates of pH-Eh were calculated using classic Pourbaix diagrams. The effectiveness of metals extraction from solutions was evaluated according to Gibbs free energy. Results. On the base of thermodynamic calculations conditions and efficiency of metals extraction by microorganisms was shown. Microbial reduction of CrО42- to insoluble Cr(III) hydroxide was the most effective. Additional carbon and energy sources are required for effective molybdate reduction. Extraction of tungstate can not be carried out by microorganisms. Conclusions. Thermodynamic prognosis is effective method for developing novel environmental biotechnologies for purification of environmentally hazardous metal-containing wastewater and simultaneous treatment of organic waste.
 Keywords: thermodynamic prognosis, microbial interaction of with metals, metals extraction,
 purification of metal-containing wastewater, environmental biotechnologies.

The resistance of chernozem soil microorganisms to soluble copper compounds

Аim. Determination of resistance of Ukrainian chernozem soil microorganisms to the influence of toxic copper(II). Methods. Content of copper-resistant microorganisms in chernozem was determined by counting colonies on a solid nutrient medium containing Cu(II). Resistance of microorganisms was determined by cultivation in the medium with concentration gradient of Сu2+. Results. Microorganisms resistant to toxic copper(II) by ultrahigh concentrations were shown to be present in chernozem soil. Microorganisms grew in the medium containing up to 500 mg/l Cu2+ (CuSO4 solution) and up to 10000 mg/l Cu2+ (in complex with citrate). Chelation of copper(II) with citrate was found to lead to increase of microbial resistance in 20 times. It was determined that a vanishingly small number of microorganisms resistant to toxic copper by ultrahigh concentrations can exist in a natural ecosystem. The number of viable microorganisms decreases with the increase in the content of Cu2+ that is described by the hyperbolic curve. Conclusions. The proposed methodological approach not only allows to isolate copper-resistant microorganisms from natural ecosystems of all geographic zones of the globe, but also avoid complex genetic transformations in order to obtain perspective genetically modified strains for further application in biotechnologies for purification of industrial wastewater.
 Keywords: copperresistant microorganisms, chernozem soil of Ukraine, diversified microbial community, environmental biotechnologies.