Chemistry. Ecology. Biotechnology

This makes it possible to optimize process of immunoglobulin production and, therefore, obtain a higher yield of a medicament per 1 liter of plasma.

This study can be used not only in production of human blood products, but also in preparation of vaccine-serum drugs.

УДК 579

V.L. Gorbushina, A.V. Portnova

STUDY OF SORPTION PROPERTIES OF HUMIC ACID FOR CLEANING MINE WATERS FROM Fe3+ IONS

Perm National Research Polytechnic University

One of the major environmental problems of the Perm krai is sewage treatment from heavy metals and their compounds. Water pollution with heavy metal ions is dangerous for the biosphere; besides, heavy metals have a toxic effect on organisms of plants and animals, tend to accumulate in food chains, which increases their danger for humans. The greatest danger for water objects constitutes acid mine water of Kizelovsky coal basin, which contained a large amount of iron oxides. Currently, there are more than ten areas of mine waters spout in its territory, which leads to contamination of rivers with iron ions at a distance of tens of kilometers. The lack of treatment plants leads to contamination of surface watercourses by acidic mine waters. This has a significant effect on the drinking water quality.

The aim of this work is to develop chemical and biological ways for treatment of acid mine waters. It is planned to receive an environmentally safe biosorbent based on humic acid with immobilized microorganisms. In future, the possibility of using the old biosorbent as a fertilizer for soils poor in organic matter content is considered.

Humic substances make up a large portion of the dark matter in humus and consist of heterogeneous mixtures of transformed biomolecules exhibiting a supramolecular structure. Today, humic substances are mostly

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used in plant growth as stimulants or as a micronutrient. Furthermore, humic substances are used for the remediation of contaminated soils and waters. They are also tried for cleaning and reclamation of areas polluted with organic substances, petroleum products and heavy metals. Humic acid (HA) of soils has a significant impact on the migration of heavy metal ions. Binding ions of heavy metals, humic acid decreases their bioavailability and toxicity.

For creation of HA-based biosorbent with immobilized microorganisms it is necessary to select the acid from the peat, extract and cultivate a culture of microorganisms from a sample of mine water, which is resistant to acidic medium and high concentrations of ions Fe3+.

Currently, the experiments of Fe3+ ions sorption by the humic acid are carried out. Humic acid was isolated from the peat by using the standard method. In the experiment the salt FeCl3x6H2O was used. The concentration of metal ions was from 0 to 100 mg/l. Determining the concentration of ions in solutions was done by atomic absorption spectrophotometer. Based on the sorption experiment with the static conditions, we can estimate the saturation degree of humic acid by ions Fe3+. The value of maximum sorption of iron ions in the experiment equals 75.2 mg/g. The maximum percentage of absorption in the experiment reached 89%. The sorption experiment will continue to determine the maximum sorption capacity of humic acid towards Fe3+ ions.

УДК 661.635

A.S. Ezhova, A.V. Vinogradova

RESEARCH INTO POTENTIAL USE OF SILICON COMPOUND AS A SOIL IMPROVER AND STABILIZER OF HEAVY METAL IONS IN CONTAMINATED SOIL

Perm National Research Polytechnic University

Global pollution has affected the environment. Soil is a very special form of the biosphere: it accumulates all the pollutants and serves as

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a natural carrier of chemical elements in the atmosphere, the hydrosphere, in plants and human food.

Heavy metal ions have special ecological significance. Heavy metals as a result of human activities can be significantly redistributed, causing their local accumulation in dangerous concentrations in natural and man-made environments. Their activity suppresses practically the whole vegetable and soil enviroment on land and water. In addition, a part of the changes accumulates in living organisms and affects the biota at the genetic level. Therefore, reducing the negative influence of heavy metals through their transfer to the sedentary state by meliorants stabilizers is a topical task.

The experiments were conducted in the containers, maintaining a constant humidity of the soil in them. Metals (lead, copper and zinc) were added as a soluble salt, based on 10 to 300 mg (as metal ion) per 1 kg of soil. The silicon as a part of liquid glass was added in the soil in the following ratio to metal ion: liquid glass to metal ion 1:0.5-1. The binding of heavy metals and transferring them to the sedentary state were investigated through the analysis of water and ammonium-acetate buffer extracts by atomic absorption spectroscopy.

The toxicity of the soil before and after remediation was examined by the catalase activity, which indirectly reflects a biological activity of the soil, and also by the results of biotesting. Bioluminescent bacteria “Ekolyum” were used as biotesters with use of the device Biotoks-10M

and algae Scenedesmus quadricauda.

The preliminary experimental results have shown that silicates being a part of the liquid glass bind around 50% of heavy metal ions to a sparingly soluble form, thereby reducing by half the toxicity of soil. For example, the initial lead concentration of 10 mg per 1 kg of soil was reduced to 5.04 mg / kg.

The experiments to find the optimal doses of an improver with different amount of heavy metals in the soil will be continued.

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УДК 544.478-03

А.V. Tsukanov, D.A. Rozhina, Y.A. Baydina,

D.A. Kazakov, V.V. Volkhin

MINERALIZATION OF p-NITROPHENOL

BY OZONATION AND BIODESTRUCTION

Perm National Research Polytechnic University

Nitrophenols are widely used in the production of pesticides, fungicides, herbicides, explosives and dyes. Nitrophenols enter the environment with the waste waters. The maximum permissible concentration of p-nitrophenol (PNP) in waters is 0.02 mg/l. Therefore, it is necessary to prevent PNP release into the environment with waste waters. Traditionally, organic compounds are removed from waste waters by biodegradation. However, there is a problem for applying this method to PNP due to the toxicity of PNP for microorganisms, especially at high concentrations. It is possible that PNP biodegradation will be more effective at optimal PNP concentration which is acceptable for microorganisms growth. For initial reduction of PNP concentration ozonation can be used and then biodestruction can be applied for a complete PNP oxidation. The aim of this study is intensifying the process of the PNP mineralization by combination of ozonation and biodestruction. The objectives of the study are: 1) isolation of PNP oxidizing microorganisms and study of PNP biodegradation; 2) preparation of biocatalyst for PNP mineralization by immobilization of microorganisms on the magnetic carrier; 3) determination of macrokinetic regime for PNP mineralization by ozonation; 4) study of the effect of homogeneous and heterogeneous catalysts for PNP mineralization on gas-liquid ozone mass transfer and the macroscopic reaction rate; 5) study of PNP mineralization using catalytic ozonation and destruction in the presence of the biocatalyst.

A mixed culture of PNP oxidizing microorganisms was isolated, which is dominated by rod-shaped bacteria.

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Influence of PNP on gas-liquid ozone mass transfer was studied (Table). It is shown that an increase of PNP concentration in the range of 0.001-0.010 mol/l led to the growth of ozone volumetric mass transfer coefficient (KLa). Further increase in PNP concentration leads to the reduction of KLa. This dependence can be explained by simultaneous increase of specific surface area (a) and reduction of ozone mass transfer coefficient (KL) upon increase of PNP concentration.

Effect of PNP concentration on ozone gas-liquid mass transfer

Note: KLa - volumetric mass transfer coefficient; KL - mass transfer coefficient; а - specific surface area.

Based on the data of ozone absorption rate during PNP mineralization an enhancement factor (E = 1,07) and Hatta number (Ha = 0,48) were determined. The obtained values of the parameters E and Ha show that PNP oxidation process by ozone occurs in diffusion regime.

УДК 546.46’185

L.I. Ismagzamova, V.V. Volkhin, G.V. Leontjevа

SYNTHESIS OF SORPTION ACTIVE Mg3(PO4)2 * 22H2O

Perm National Research Polytechnic University

Crystalline hydrate Mg3(PO4)2 * 22H2O structure includes ions Mg(H2O)62+ and PO43-, which are united only by hydrogen bonds with molecules H2O.

Because of the hydrogen bonds low energy the ions Mg(H2O)62+ 3- should have an increased lability, which creates conditions for

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their transformation into the liquid phase and participation in chemical reactions with other ions present in the solution. Thus, it can form poorly soluble compounds. Therefore, there is a possibility to use this in remediation technology for the soils contaminated with heavy metals.

However, the results of the experiments showed that Mg3(PO4)2 · 22H2O characterized by metastability and other crystalline hydrates, which do not have necessary absorption properties, are formed in the synthesis. Therefore, this required a more thorough synthesis optimization.

The basis of the Mg3(PO4)2 · 22H2O synthesis method is a normal interaction of the ions Mg2+, HPO42– in excess water. But it is important to define the conditions of particular crystalline synthesis. A series of experiments were conducted to clarify the conditions of synthesis, where the effect of ion concentration, pH value and exposure time of the sludge were studied. The results showed that the solutions interaction of 0.1М MgCl2 and 0.1M Na3PO4 in stoichiometric relationship at pH>9.5 leads to the formation of Mg3(PO4)2 · 22H2O. The solution temperature also matters. At temperatures above 25-30 °С it can form a stable structure Mg3(PO4)2 · 8H2O. However, an exposure of Mg3(PO4)2 · 22H2O in the mother liquor at room temperature is sufficient for the gradual water loss of crystallization, which can lead to the formation of bridge bonds - O- between PO43- and Mg2+ in the composition of the solid phase and loss of sorption properties. Complete dehydration of crystalline occurs during the sludge heat treatment.

The next step was to test the ability of Mg3(PO4)2 · 22H2O to absorb heavy metal ions. It shows that crystalline hydrate is able to absorb heavy metal ions Ni2+ and forms Mе3(PO4)2 · 8H2O, where Me is a heavy metal ion. The further studies are planned in relation to remediation of the soils contaminated with heavy metal ions.

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УДК 579.695

I.I. Sokolova, D.A. Kazakov, V.V. Volkhin

PREPARATION AND PROPERTIES INVESTIGATION OF A MAGNETICALLY SEPARATED BIOCATALYST FOR PHENOL OXIDATION

Perm National Research Polytechnic University

Concentration of phenol in nature waters should not exceed 0.001 mg/l in accordance with the maximum permissible concentration. Therefore, its release into environment should be prevented. Biological decomposition of phenol is complicated because of its toxicity for microorganisms. The effectiveness of toxic substrates biodegradation including phenol can be increased by using immobilized microorganisms as a biocatalyst. Such biocatalysts are characterized by a higher stability compared with the free cells. Furthermore, these biocatalysts can be used repeatedly in the technological process. However, after the biodegradation process fine particles of biocatalyst should be removed from the aqueous phase, which complicates the process. A potential approach to solving this problem is the development of magnetic biocatalysts that can be easily removed from the aqueous phase by using a magnetic separation. Accordingly, the purpose of this study is preparation and properties investigation of the magnetic biocatalyst for phenol oxidation. The objectives of the research are 1) isolation of phenol oxidizing microorganisms, study of dynamics of phenol biodegradation and kinetics of microorganisms growth; 2) preparation of the magnetically separated carrier for the biocatalyst, study of equilibrium and kinetics of phenol adsorption on the obtained carrier; 3) preparation of biocatalyst for phenol oxidation by immobilization of microorganisms on the magnetically separated carrier, study of phenol oxidation in the biocatalyst presence.

Phenol oxidizing microorganisms from water of Pyzh river (Perm) were isolated. The study of phenol biodegradation and kinetics of microorganisms growth was started. The synthesis of the magnetically sepa-

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rated carrier for the biocatalyst was carried out. Equilibrium and kinetics of phenol adsorption on this carrier were studied. It was shown that the isotherm of phenol adsorption on the magnetic carrier was described by Lengmuir’s equation with the following parameters: constant of adsorption equilibrium K = 0.236 l/mg; adsorption capacity A∞ = 80 mg/g. It was shown that kinetics of phenol adsorption on the magnetic carrier was described by the equation of pseudo-second order kinetic model.

УДК 579.695

A.E. Osheva, D.A. Kazakov, V.V. Volkhin

BIOCATALYTIC OXIDATION OF 4-NITROPHENOL BY MICROORGANISMS IMMOBILIZED

ON THE COMPOSITE MAGNETIC CARRIER

Perm National Research Polytechnic University

Nitroaromatic compounds such as 4-nitrophenol are widely used in the production of fungicides, pesticides, dyes and pharmaceuticals. Concentration of 4-nitrophenol in nature waters should not exceed 0.02 g/m3 in accordance with ecological standards and that is why its release into the environment must be prevented. Biodegradation can be used to remove 4-nitrophenol from the aqueous medium. The main problem of the biodegradation use for 4-nitrophenol removal is its toxicity for microorganisms, especially at high concentrations of this xenobiotic. It is assumed that at high 4-nitrophenol concentrations the efficiency of its biodegradation can be improved through the use of immobilized microorganisms. Magnetic particles can be used for microorganisms immobilization for an easier biocatalyst removal on the basis of immobilized microorganisms from aqueous phase after biodegradation process. The data about effectiveness of 4-nitrophenol removal from aqueous media using systems that include microorganisms and magnetic carrier are absent in the literature. In accordance with this, the research purpose is investigation of 4-nitrophenol biocatalytic oxidation by

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microorganisms immobilized on the magnetic carrier. The objectives of the research are: 1) isolating of microorganisms which oxidize 4-nitrophenol, study of kinetics of 4-nitrophenol biodegradation and microorganisms growth; 2) obtaining of magnetic carrier for microorganisms immobilization, study of equilibrium and kinetics of 4-nitrophenol adsorption on the obtained carrier; 3) obtaining of biocatalyst by physical immobilization of microorganisms on magnetic carrier; 4) study of 4-nitrophenol degradation kinetics under the influence of the biocatalyst.

Isolation of 4-nitrophenol oxidizing microorganisms from sewage sludge was carried out. A composite magnetic carrier was prepared by precipitation of magnetite in the presence of activated carbon particles. Equilibrium and kinetics of 4-nitrophenol adsorption on the obtained carrier were studied. An isotherm of 4-nitrophenol adsorption on magnetic carrier was plotted. The parameters of Langmuir equation were calculated: monolayer adsorption capacity A∞ = 158.7 mg/g and constant of adsorption equilibrium K = 0.148 l/mg.

The further studies will be aimed at obtaining biocatalyst by physical immobilization of microorganisms on the magnetic carrier, as well as the study of the kinetic characteristics of 4-nitrophenol degradation by the biocatalyst.

УДК 579.695

R.G. Khaybullin, D.A. Kazakov, V.V. Volkhin

REMOVAL OF CATECHOL FROM AQUEOUS SOLUTIONS

USING MAGNETIC BIOCATALYST

Perm National Research Polytechnic University

A broad application of catechol in organic synthesis, pharmaceuticals and perfumery production leads to its intensive release to environment through wastewaters. The concentration of catechol in water reservoirs in accordance with the ecological standards should not exceed 0.1 mg/l. Thus,

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release of catechol into environment must be prevented. Biological wastewater treatment is considered promising at present. This involves mineralization of organic compounds by microorganisms which use them as the carbon and energy source. The biodegradation efficiency of toxic substrates, including catechol, can be improved by using microorganisms immobilized on solid fine particles as carriers. Removing such biocatalysts from the aqueous phase after using them is difficult. The development of magnetic biocatalysts which can be easily separated from the aqueous phase under the constant magnetic field can be considered as an approach to solving this problem. The aim of this work is to study the process of catechol removal from aqueous solutions using magnetic biocatalyst. The objectives of the study are 1) extraction of catechol-oxidizing microorganisms, study of catechol mineralization dynamics by the extracted microorganisms; 2) synthesis of the magnetic carrier, study of kinetics and equilibrium of catechol adsorption on this carrier; 3) preparation of the biocatalyst by means of physical immobilization of the microorganisms on a magnetic carrier; 4) study of catechol mineralization using the magnetic biocatalyst.

A culture of catechol-oxidizing microorganisms was isolated from the sewage sludge of biological treatment facilities (“LUKOIL-Perm- nefteorgsintez” LLC). The studies of the microorganism’s growth kinetics and catechol biodegradation dynamics were started. A synthesis of the magnetic carrier from activated carbon and magnetite (Fe3O4) was carried out. Catechol adsorption equilibrium on magnetic carrier has been studied. The Langmuir equation parameters (adsorption equilibrium constant K = 7.3·10-3 and adsorption capacity A∞ = 83.3 mg/g) were determined. It was shown that kinetics of catechol adsorption on the magnetic carrier can be described by the pseudo-second order kinetic model.

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