Water and water purification technologies

Scientific and technical news

SORPTION REMOVAL DYES FROM WATER BY NANOCOMPOSITE MAGNETICALLY MINERAL SORBENTS

O. V Makarchuk, T. A Dontsova

National Technical University of Ukraine “Kyiv Polytechnic University”, Kyiv

xtfhn9207@ukr.net, dontsova@ua.fm

The sorption of dyes from aqueous solutions by magnetically sorbent based on saponite and nanomagnetite are considered and shown that it is effective adsorbent for dyes as cationic and anionic nature. The suitability of various kinetic models (pseudo-first and pseudo-second-order) and models of sorption isotherms (Langmuir, Frendlih, Tiomkin and Dubinin-Radushkevych) to describe the adsorption interaction between dyes and adsorbent are analyzed. The rate constants are calculated and found that process of organic dyes adsorption by nanocomposite magnetically sorbent describes the kinetics model of pseudo-second order. Revealed that the process of sorption Malachite green, Congo red, Indigo carmine by magnetically sorbent described Langmuir model.

Keywords: magnetically sorbent, saponite, magnetite, dyes, kinetics, adsorption, magnetic separation.

07.04.2016 at 9:04 pm

ANALYSIS OF ABILITY TO APPLICATION OF EFFECTIVE SORBTION MATERIALS FOR LIQUID WASTE TRAETMENT ON THE NUCLEAR PLANTS OF UKRAINE

T.V. Maltseva

Vernadsky Institute of general and inorganic chemistry NAS Ukraine, Kiev, Ukraine

e-mail: maltseva@ionc.kiev.ua

Sorption materials that are being used at the plant, similar to Ukrainian ones, and perspective has been considered to solve effectively the problem of reducing the volume and conditioning of liquid radioactive waste at nuclear power plants in Ukraine. The chemical and radionuclide composition of initial and the concentrated waste as well as selection criteria for sorption or filter materials towards dominant radioactive contaminants have been analyzed. It is represented the research results about adsorption of cesium and strontium ions by: (1) some organic cation exchange resins with differing degree of crosslinking, and (2) synthetic individual and double metal oxyhydrates of IY group, and (3) compounds based on ZrO2, modified phosphate Zr (IV) and Mo (VI). The value of the distribution coefficient of radioactive components at the absorption on the inorganic adsorbents reaches 105 см3·г-1. In the study of the absorption of strontium ions from dilute solutions on the organic cation exchanger Dowex HCR-S the local area of non-exchange electrolyte absorption was observed on adsorption isotherm. That is why in spite of high values of distribution coefficients which are closed to ones for inorganic sorbents it can be concluded that organic resins are not selective.

Key words: adsorbents, selectivity, nuclear waste, distribution coefficient, coefficient of volume reduction. 

07.04.2016 at 9:00 pm

IDENTIFICATION OF MICROORGANISM DRINKING TAP WATER RESISTANT SODIUM HYPOCHLORITE

I.Y Roi, N.A Klimenko, G.M. Zdorovenko, V.V. Goncharuk

Institute of Colloid and Water Chemistry named Dumansky NAS , Kiev

roy_inka@ukr.net 

The morphological and cultural characteristics of the three dominant bacterial cultures isolated from drinking tap water and water samples at different stages of post-treatment on the installation of water treatment companies of special drinks were studied. From the sequence of the 16S rRNA gene identified the following types of bacteria: Bacillus nanhaiensis, Brevibacterium frigoritolerans and Lysinibacillus fusiformis. It was found that the most resistant to chlorine appeared Lysinibacillus fusiformis. Its resistance to sodium hypochlorite (NaClO) at concentrations of 1.4; 3; 5; and 7 mg / l varies from 1 – 98%, while the duration of exposure of from 5 to 60 minutes, while the remaining two isolates Brevibacterium and Bacillus nanhaiensis frigoritolerans demonstrated lower survival in the presence of NaClO (0 – 16%). A parallel between the morphological type selected bacterial isolates, their ability to form a pellicle at the interface liquid / air and resistant to chlorine is drawn. This resistance to a sufficiently high concentration of sodium hypochlorite may develop as a result of natural selection through random mutation and / or due to the effect of the disinfectant, which can induce the occurrence of acquired resistance.

Keywords: bacterial biofilm, resistance, sodium hypochlorite, Bacillus nanhaiensis, Brevibacterium frigoritolerans, Lysinibacillus fusiformis.

07.04.2016 at 8:56 pm

WATER QUALITY ASSESSMENT IN THE SOUTHERN BUG IN POWERFUL PLACE OF DRINKING WATER INTAKE IN VINNYTSIA REGION

I.S. Yezlovetska, V.S. Shunkov, S.N. Bulanuk

A.V. Dumansky Institute of colloid chemistry and water chemistry of NAS of Ukraine, Kyiv

National Pirogov memorial medical University,

Department of river Basin Water Resources of the Southern Bug, Vinnytsia

i.ezlovetskaya@ukr.net, shunkov.vasiliy@yandex.ru

The water quality assessment of the upper and middle portions of the Southern Bug river (in the area of quality drinking water intake in Vinnytsia region) is performed. It is done base on ecological and hygienic criteria in order to obtain a clear view about environmental state of water resources of the basin of the Southern Bug and the water quality of natural as raw material for the production of drinking water. The specifics of the assessment is to ascertain the natural conditions for the formation of quality river water in the summer-autumn low water medium in water period. A comparison of water quality of the upper and middle portions of the Southern Bug river in the district is a representative of drinking water intake. As defined in the general list of priority, water quality parameters, which are crucial in adjusting existing water treatment technologies in wastewater-conditioning plants is the choice of modern methods and techniques of conditioning natural water. It is revealed that these parameters include odor, color, turbidity, total hardness, alkalinity and the pH value, content of organic and biogenic substances, the abundance and biomass of phytoplankton, a number of microbiological and toxicological parameters. The proposed addition to the existing modern methods of intensification of the conditioning processes include chemical and physical methods that improve the processing conditions and water-conditioning processes.

Keywords: water quality, hygiene and environmental criteria, priority indicators, water-conditioning.

07.04.2016 at 8:51 pm

METHODS OF DETERMINE OF MAGNETIC-RECEPTIVE IMPURITIES IN LIQUID MEDIA

V.I. Garashchenko, А.V. Garashchenko, V.V. Drevetsky, А.А. Lebed

National University of Water Management and Nature Recources Use, Rivne, Ukraine

e-mail: vigarashchenko@yandex.ru

The analysis of existing methods and magnetic analyzers used to determine the magnetic fraction of impurities was performed. Their advantages and disadvantages was shown. A method for determining the magnetic fraction of impurities, based on repeated cyclical filtration of aqueous samples using laboratory magnetic filter with ferromagnetic filtering nozzle, which has anti-corrosion properties was offered. Large-scale studies for determine the fraction of magnetic impurities in technological waters of Tiraspol, Ostroh, Odessa, Krasnodar, Kherson, Shymkent and Kalush CHP, Uglegorsk TPP and chemical plant “Russia” were conducted. It was shown that, despite the differences in aquatic environments electric utilities in chemical composition and temperature conditions, the magnitude of the magnetic fraction in the technological waters is about 72-98%. It was proposed the experimental-computational method for determining the magnetic fraction of impurities, based on the experimental depending of change of the iron concentration from magnetized filtering nozzle length. With the using of formulas that provided in the article calculates the value of the magnetic fraction. To determine the fraction of magnetic impurities in technological waters (when impurities having sizes of 0.01-10 microns and a concentration of 30-100 g/dm3) an improved magnetic analyzer with flocculation chamber was proposed. In the flocculation chamber there is an integration of impurities, as a result the number of cycles in determining the magnetic fraction decreases by 1.5 times and the time of analysis is reduced.

Keywords: magnetic impurities fraction, ferromagnetic filtering nozzle, magnetic filtration.

07.04.2016 at 8:47 pm

INFLUENCE OF SURFACE CHEMISTRY OF ACTIVATED CARBON ON THE ADSORPTION OF NATURAL ORGANIC MATTER

L. Savchyna

A.V. Dumansky Institute of colloid chemistry and water chemistry of NAS of Ukraine, Kyiv

e-mail: savchyna.l@gmail.com

Adsorption of peat fulvic acids from neutral aqueous solutions on non-oxidized and oxidized active carbon with and without hydrogen peroxide was investigated. Influence of surface groups of active carbon (АС) on equilibrium adsorption of fulvic acids from aqueous solutions was estimated. It was shown that fulvic acids adsorption efficiency has been advanced by ~ 49% with the replacement of non-oxidized carbon to oxidized one.

Keywords: active carbon, fulvic acids, oxidized carbon, adsorption equilibrium, redox potential.

07.04.2016 at 8:42 pm