The article illustrates the results of the research dedicated to finding a method of combining two polymeric materials - ion-exchange membranes having different chemical nature. It shows a method of applying a homogenous film MF 4SK on the surface of the heterogeneous membrane substrate to produce a chemically and mechanically stable asymmetric bipolar membrane. We have selected membrane substrate ensuring the best electrochemical performance
The article presents the results of studies of changes in
the atomic radii of the elements of the periodic table,
depending on their atomic masses. It is shown that the
appearance of p- and d-orbitals introduces a significant
contribution to the value of the atomic radius, and the
appearance of f-orbitals makes a significantly smaller
contribution to the given value. A radial-mass model of
calculations of atomic radii for the elements of the
Periodic Table was developed. Optimal conditions for
making calculations were chosen. For the first time the
values of atomic radii for elements with the order
number 103-120 are calculated. It is shown that the
values of atomic radii for elements with the order
number 103-120 are in the range from 140 to 335
picometers and regularly change in the period
Data of application of researches of vegetative components in reception of drinks from dairy whey of a functional purpose are shown
The article presents the experimental results of the
study of the concentration dependence of the electrical
conductivity of heterogeneous ion-exchange
membranes that are in contact with solutions of weak
electrolytes - carboxylic acids. It is shown that in this
case the membrane conductivity is higher than the
conductivity of the solution, wherein the conductivity
of cation exchange membranes substantially greater
(by an order of magnitude) than the conductivity of
anion exchange membranes. This fact must be
considered when designing the actual electrodialysis
processes of processing solutions containing organic
ions. The work identified the need to develop modern
ideas about transport and the structural organization of
ion-exchange materials, to describe the structure of the
ion-exchange membranes that are in contact with weak
electrolytes solutions
The stability of strongly basic anion-exchange membranes MA-41-2P (JSC "Schekino-Nitrogen", Russia) and AMX (Tokuyama Soda, Japan) under intensive current regimes was investigated in the
current study. The process of water molecules dissociation at current densities above the limiting one in 0.01 M sodium chloride solution was studied in detail. The length of the electroconvective instability at the membrane / solution interface at currents
exceeding the limiting current was measured by laser interferometry
In the article, we have investigated a number of characteristics of the sorption materials, the possibility of their use for the treatment of surface and waste water from oil and oil products. The rules of the cleaning oily water, the analytical solution for sorption purification process that takes into account the processes of filtration and sorption are listed. We have also estimated sorption capacity of sorbents and analyzed factors that influence it; the optimal conditions of the sorption process, depending on the conditions and the facilities for cleaning are sorted out. The possibility of purification of oil-contaminated water from heavy metal ions with the synthesized non-organic sorbent is shown
In this article, the recycling problem of oil sludge on some modern refinery factories is observed. We studied physical and chemical structure of oil sludge and offered a new way of neutralization of oil sludge. It is established, that if we replace a carbon sorbent to sorbent that contains silica for oil sludge neutralization, we will get environmental safe product. As such sorbent, which contains silica we offer to use a burnt rice peeling. For practical realization the way of neutralization is developed and technological scheme which allows to save natural resources (hydrocarbons and water) and return it to production cycle and to recycle the petropolluted sludge is offered
The results of study of bipolar membrane – analogue
of MB-2, modified with chemically introduced chromium
(III), iron (III) and nickel (II) hydroxides by the
method of frequency spectrum of electrochemical impedance,
by infrared spectroscopy and scanning electron
microscopy in combination with X-ray spectrum
analysis are presented. It is shown, that sequential
treatment of cation-exchanger, contained in cationexchange
membrane, with metal salt solution and alkali
solution does not result in formation of complex
compounds of these metals with ionic groups of ion
exchanger. It was found that in these conditions the
presence of heavy metals in the phase of cationexchanger
confirmed by X-ray analysis, however,
crystals of hydroxides of heavy metals are not detected
in the size range of 1000 nm to 20 nm. These heavy
metal compounds are thermally unstable and their
catalytic activity in the reaction of dissociation of water
molecules decreases with increasing temperature
during heat treatment. The introduction of low-soluble
hydroxides of d-metals (chromium (III), iron (III),
nickel(II)) by chemical method can significantly improve
the electrochemical characteristics of a bipolar
membrane. The most effective catalysts in water dissociation
reaction are the hydroxides of chromium (III)
and iron (III) and, as a consequence, membranes with
these hydroxides have a lower value of overpotential
compared with original membrane at the same current
density
The article discusses results of experimental research
of the influence of aprotic and proton solvents on reaction
rate of water molecules dissociation in the bipolar
membrane MB-1 by the method of electrochemical
impedance frequency spectrum. It was discovered, that
addition of organic component in aqueous solutions results
in significant influence on the parameters of water
dissociation in a bipolar region of the membrane.
The reason for this influence is the reduction of the
mass fraction of water in solution and, consequently,
in a bipolar region of the membrane, which itself reduces
the rate of the dissociation reaction. Another
reason for the influence of the organic solvent is its effect
on the network of hydrogen bonds existing in water
and aqueous solutions. Depending on the nature of
organic solvent and its concentration, the network of
hydrogen bonds may be strengthened, or destroyed,
thus facilitating removal of the proton involved in the
reactions between water molecules and catalytic centers
in cation-exchange and anion-exchange layer of
bipolar membrane, or retarding removal of proton.
This leads respectively to speed up or slow down the
rate of dissociation in the bipolar region of the membrane,
as well as changing the constants of the dissociation
reaction of water. Introduction of organic solvent
in solutions, which are in the contact with bipolar
membrane, is a convenient method of investigating the
role of solution composition on the rate of proton
transfer between water molecules and catalytic centers
in the membranes
In this article, we discuss the relationship between the
previously obtained model for calculating atomic radii
with electrodynamics, the hydrodynamic model of the
planets of the Solar System, and the R-function of the
structural organization of electronic systems. It is
shown that the curve of the dependence of the value
of the correction coefficient e
x
on the atomic number
of the element in form coincides with the dependence
of the ionization energy on the mass of the atom and
the R-function on the nuclear charge. The concept of
the "atomic nucleus potential", which takes into
account the energy of the nucleus and the charge of
the nucleus of the atom, is introduced. It is shown that
the radius of an atom is the product of the nuclear
potential by a factor kx
, taking into account the
characteristics of electronic levels; the energy of the
nuclear reaction is the work of the forces of the field
(potential) of the atomic nucleus along the
displacement of the atomic charge. The dependence of
the potential of the nucleus on the charge number in
the Mendeleev’s Periodic Table is shown. It is shown
that any system of satellites (or atomic shells) has a
constant ratio of its Kepler number to the mass of the
central body around which they rotate. It is shown that
in the Table of Mendeleev's chemical elements and in
the solar system, the fundamental value is the mass of
the center (the nucleus of the atom or the center of the
orbit). The ratio of the Kepler number to the mass of
the central body is a constant, within the accuracy of
construction and calculations