Рисунок 1 – Зависимость привиденной вязкости анионного полиэлектролита
водного раствора в разных концентрациях NaКМЦ полимера на концентрацию NaCl
Рисунок 2 – Влияние концентрации NaCl 1·10
-2
М (1), 1·10
-1
М (2) и водного
раствора NaКМЦ в концентрациях 5·10
-1
М (3) 6,25·10
-2
г/дл на концентрацию ЦТАБ
ХИМИЯ ЖӘНЕ ХИМИЯЛЫҚ ТЕХНОЛОГИЯ БОЙЫНША IX ХАЛЫҚАРАЛЫҚ БІРІМЖАНОВ СЪЕЗІНІҢ ЕҢБЕКТЕРІ
147
Рисунок 3 – Зависимость привиденной вязкости водного раствора Zetag 92 на
концентрацию полимера
Результаты и обсуждения
Применения высокомолекулярно-композиционных дезинфицирующих средств
является популярным методом для очистки воды. На практике это можно осуществить
путем добавления непосредственно в воде. Поэтому нерастворимые в воде бактерицидно-
активные интерполимерныекомплексы метацида десорбцируются в воде легко и
применяются целях профилактики.
В ходе исследования обнаружена различная зависимостьхарактера флокуляции от
дозы добавленного полиэлектрита в случае разбавленной и относительно
концентрированной суспензии.
Заключение
Дано объяснение этой зависимости, основанное на допущении различной степени
приближения флокулянта, адсорбированного на поверхности частиц, к равновесному
состоянию
при
вариации
содаржания
дисперсной
фазы.
Результаты исследования вязкости и оптической плотности водных растворов смесей
катионного и анионного полиакриламидов указывают на образование электростатических
комплексов между ними, что приводит к усилениюих флоккулирющего действия.
Список литературы
1
IUPAC. Compendium of Chemical Terminology. 2nd ed. (the «Gold Book») /
Compiled by A.D. Mc- Naught, A. Wilkinson. — Oxford: Blackwell Scientific Publications,
1997. —
2
Абрамзон А. А., Поверхностно-активные вещества. Свойства и применение, 2
изд., Л., 1981; Успехи коллоидной химии, под ред. П.А. Ребиндера и Г. И. Фукса, M.,
1973; то же, под ред. Ф. Д. Овчаренко, К., 1983; то же, под ред. И. В. Петрянова-Соколова
и К. С. Ахмедова, Ташкент, 1987.
3
Кутц Г. Косметические кремы и эмульсии: состав, получение методы испытаний.
Пер. с нем. / Под ред. М.Ю. Плетнева. М.: ООО «Фирма Клавель»/ Издательский дом
«Косметика и медицина», 2004
ХИМИЯ ЖӘНЕ ХИМИЯЛЫҚ ТЕХНОЛОГИЯ БОЙЫНША IX ХАЛЫҚАРАЛЫҚ БІРІМЖАНОВ СЪЕЗІНІҢ ЕҢБЕКТЕРІ
148
4
Русанов А.И. Мицеллообразование в водных растворах поверхностно-активных
веществ. – СПб.: Химия, 1992.
5
Плетнев М.Ю. Мицеллообразование и специфические взаимдоействия в водных
растворах смесей ПАВ // Успехи коллоидной химии / Под ред. А.И.Русанова. – СПб.:
Химия, 1991. – С. 82.
ХИМИЯ ЖӘНЕ ХИМИЯЛЫҚ ТЕХНОЛОГИЯ БОЙЫНША IX ХАЛЫҚАРАЛЫҚ БІРІМЖАНОВ СЪЕЗІНІҢ ЕҢБЕКТЕРІ
149
Nazarkulova Sh.N.*, Matveyeva I.V., Satybaldiyev B., Uralbekov B.M., Burkitbaev M.M.
Al-Farabi Kazakh National University, Almaty, Kazakhstan
E-mail:
sholpan.nazarkulova@kaznu.kz
Uranium isotopes and uranium speciation in the waters of Syr-Darya river
Chemical and radiochemical analysis was carried out on 7 water samples from Syr-Darya
river in 2013. All samples were analyzed for main ions such as Ca
2+
, Mg
2+
, HCO
3
-
, CO
3
2-
, Cl
-
via
titrimetric methods, SO
4
2-
via gravimetric method and U isotopes via alpha-particle
spectrometry. The results of analysis of chemical composition of water showed that the main
components of water are sulfate and magnesium ions. The concentration of uranium ranged from
14.7 to 17.3 µg/l. These data were used to calculate uranium speciation in the waters for
predicting its mobility in river ecosystem. Calculated results showed that the main speciation of
uranium at the investigated territory are [UO
2
(CO
3
)
2
(H
2
O)
2
]
2-
, [UO
2
(CO
3
)
3
]
4-
and
[UO
2
OH]
+
. The
obtained uranium species are water-soluble and as a result can migrate on long distances,
influencing on radioecological situations of large territories.
Keywords: uranium speciation, mine, Syr-Darya river, water, migration.
Назаркулова Ш.Н., Матвеева И.В., Сатыбалдиев Б.С., Уралбеков Б.М., Буркитбаев
M.M.
Әл-Фараби атындағы Қазақ ұлттық университеті, Алматы, Қазақстан
Сырдария өзені суындағы уран изотоптары мен уранның табылу формалары
Химиялық және радиохимиялық зерттеу жұмыстары 2013 жылы Сырдария өзені
бойынан алынған 7 су үлгісімен жүргізілді. Барлық су үлгілерінде негізгі иондар Ca
2+
,
Mg
2+
, HCO
3
-
, CO
3
2-
, Cl
-
(титриметраиялық әдіс), SO
4
2-
(гравиметриялық әдіс) мен U
изотоптары (альфа-спектрометриялық әдіс) анықталды. Судың химиялық сараптамасы су
құрамында сульфат және магний иондары басым екендігін көрсетті. Уран концентрациясы
14,7-ден 17,3 мкг/л-ге дейінгі аралықта өзгереді. Алынған мәліметтер өзен суындағы
уранның табылу формаларын есептеп, өзен экожүйесіндегі уранның мобильдігін болжау
үшін пайдаланылды. Есептеулер нәтижесі зерттелетін аймақта уран негізінен
[UO
2
(CO
3
)
2
(H
2
O)
2
]
2-
, [UO
2
(CO
3
)
3
]
4-
және
[UO
2
OH]
+
түрінде болатындығын көрсетті.
Анықталған уран формалары суда жақсы еритіндіктен, ұзақ қашықтықтарға
миграцияланып, үлкен аймақтардағы радиоэкологиялық жағдайға әсерін тигізеді.
Түйін сөздер: уранның табылу формалары, өндіріс, Сырдария өзені, су, миграция.
Назаркулова Ш.Н., Матвеева И.В., Сатыбалдиев Б.С., Уралбеков Б.М., Буркитбаев
M.M.
Казахский национальный университет им. аль-Фараби, г. Алматы, Казахстан
Изотопы и формы нахождения урана в воде реки Сырдарья
Проведен химический и радиохимический анализ 7 проб воды реки Сырдарья 2013 г.
отбора. Все образцы проанализированы на содержание основных ионов, таких как Ca
2+
,
Mg
2+
, HCO
3
-
, CO
3
2-
, Cl
-
титриметрическими методами, SO
4
2-
гравиметрическим методом и
изотопов U альфа-спектрометрическим методом. Результаты анализа химического состава
воды выявили, что основными компонентами воды являются сульфат-ионы и ионы
магния. Концентрация урана варьируется в диапазоне от 14,7 до 17,3 мкг/л. На основании
ХИМИЯ ЖӘНЕ ХИМИЯЛЫҚ ТЕХНОЛОГИЯ БОЙЫНША IX ХАЛЫҚАРАЛЫҚ БІРІМЖАНОВ СЪЕЗІНІҢ ЕҢБЕКТЕРІ
150
экспериментальных данных были рассчитаны формы нахождения урана для
прогнозирования миграционной способности в речной экосистеме. Результаты расчетов
показали, что основными формами урана на исследуемой территории являются
[UO
2
(CO
3
)
2
(H
2
O)
2
]
2-
, [UO
2
(CO
3
)
3
]
4-
и
[UO
2
OH]
+
. Полученные формы нахождения урана
являются водорастворимыми и, следовательно, могут мигрировать на большие
расстояния, оказывая влияние на радиоэкологическую ситуацию больших территорий.
Ключевые слова: формы урана, добыча, река Сырдарья, вода, миграция
Introduction
The territory of the Southern Kazakhstan is unique uranium province. Chu-Syrdarya
uranium deposits located on this territory are among the largest in the world regions of the
deposits connected with bed oxidation zone, localized in the permeable sediments and amenable
for in-situ leach mining. Technological works on extraction and processing of uranium ores are
held on the territory since 1950s. One of the main water arteries in the area is the Syr-Darya
River, which is actively used by local population as the main source of drinking water and water
for irrigation. The assessment of influence of radionuclides to environmental system (especially
waters) of Syr-Darya River Basin is important.
To assess the environmental impact of radioactive contamination of ecosystems,
information on source term, mobility and transport, ecosystem transfer, biological uptake and
effects is essential. Due to time dependent transformation processes the original distribution of
radionuclides, and their speciation, deposited in the environment will change over time. Due to
interactions with soil components, mobile radionuclides can be retained and the biological
uptake in vegetation can be reduced over time. Following particle weathering, however,
associated radionuclides can be mobilized and the biological uptake can increase over time.
These processes cannot be understood or predicted from the measurements of total activity
concentrations of radionuclides only. Therefore, information on radionuclide species is essential
to reduce the overall uncertainties in environmental impact assessments [1]. So the main goal of
this investigation was to calculate the speciation of uranium isotopes in water samples, which
will help to predict the behavior of uranium in environment.
Site Description.
The Syr-Darya Basin, which covers an area of 444 000 km
2
, is one of the
two major basins in Central Asia. The Syr-Darya River source flows out of the Tian-Shan
Mountains of Kyrgyzstan, located to the north of the Pamirs. It has two main tributaries—Naryn
and Kara Darya—which merge in eastern Uzbekistan to form the Syr-Darya proper, running
approximately 2500 km through Kyrgyzstan, Tajikistan, Uzbekistan, and Kazakhstan, before
finally flowing into the Aral Sea.
Most of the Syr-Darya flow, 75.2 % is formed within
Kyrgyzstan; Uzbekistan contributes 15.2 %, Kazakhstan - 6.9 %, and Tajikistan - 2.7 %. Both
rivers flow into the Aral Sea. Summer temperatures reach 40
0
C and winter temperatures fall to -
20
0
C. Precipitation is minimal, and average annual precipitation is approximately 100 mm,
which generally occurs in spring and autumn. There is a typical continental climate [2].
Experiment
1
Sampling and analysis
The sampling was carried out downstream from Turkestan city to Kyzylorda city (7
sampling points), in May, 2013. The geographical coordinates were determined by a portable
global positioning system (Garmin GPS 12 XL). The physical-chemical parameters of water
(e.g., pH, O
2
, temperature) were determined in-situ by HACH portable water laboratory. The
surface water samples were taken in water prewashed polyethylene containers with a capacity of
5÷10 liters. Preservation was carried out with nitric acid for radionuclide analysis to prevent
precipitation of heavy metals on the surface of containers and prevent biodegradability.
Furthermore, 2÷3 liter of water sample was not acidified, as it was used for the chemical analysis
ХИМИЯ ЖӘНЕ ХИМИЯЛЫҚ ТЕХНОЛОГИЯ БОЙЫНША IX ХАЛЫҚАРАЛЫҚ БІРІМЖАНОВ СЪЕЗІНІҢ ЕҢБЕКТЕРІ
151
on main cations and anions of the water, which was done immediately after delivery to the
laboratory using standard hydrochemical procedures [3].
The determination of uranium isotopes in water samples was done as described elsewhere
[4]. The procedure applied includes alpha-spectrometry with radiochemical pre-concentration
(co-precipitation on iron hydroxide, tributylphosphate (TBP) extraction and electrochemical
deposition on steel disc). The
232
U was used as a tracer for determination of radiochemical
recovery. The separation of uranium isotopes was done by extraction with 30% solution of TBP
in toluene, washed several times by equal volume of 7M HNO
3
and 0.04 HF in 0.25M HNO
3
.
The re-extraction was done by washing of TBP with distilled water several times. The obtained
re-extract was evaporated and dissolved in 0.5 M HNO
3
and 1% Trilon B. The electrolyte was
added to the solution, included equal volumes of 25% M ammonium chloride and saturated
solution of ammonium oxalate. The pH of the solution was controlled to be 8-9. The
electrodeposition was performed at 1A and during 40-45 min. The obtained stainless disc with
uranium isotopes was used for alpha-spectrometry measurements. Alpha-emissions from
samples containing uranium isotopes were detected using passivated (ion-) implanted planar
silicon (PIPS) detectors of alpha-spectrometer “Canberra”.
2 Calculation of the speciation of uranium in water
The uranium in the aqueous medium can be presented in the following speciations:
U
=
]
)
(SO
[UO
+
]
)
(SO
[UO
+
]
SO
[UO
+
]
Cl
[UO
+
]
)
(CO
[UO
+
]
O)
(H
)
(CO
[UO
+
]
OH
[UO
+
]
[UO
4
2
4
2
4
2
+
2
3
2
3
2
+
2
+
2
2
4
3
2
2
4
3
2
2
2
2
Calculation of concentrations of individual complex compounds are based on the
concentration of complexing ions, the total uranium concentration and pH values of studied
water. Calculation of chemical forms of uranium was carried out using the following analytical
expressions of the equilibrium constants:
9,8
10
=
OH
a
a
a
+
2
UO
OH
+
2
2
UO
14,7
2
2
2
2
10
2
=
O)
(H
)
(CO
a
a
a
3
2
UO
2
3
CO
+
2
2
UO
18,3
4
3
10
3
=
)
(CO
a
a
a
3
2
UO
2
3
CO
+
2
2
UO
0,39
10
=
Cl
a
a
a
+
2
UO
Cl
+
2
2
UO
1,70
10
=
SO
UO
SO
UO
4
2
2
4
+
2
2
2,55
2
2
2
10
=
)
(SO
UO
SO
UO
4
2
2
4
+
2
2
3,40
4
3
3
10
=
)
(SO
UO
SO
UO
4
2
2
4
+
2
2
where: a is activity of ions, mol/l; [] is ion concentration, mol/l.
Results and discussion
The concentrations of the main ions and uranium concentration in water samples are
presented in Table 1.
Table 1 – Chemical composition of water samples
#
Samping place
рН
The ionic composition, mmol/ l·eq
С (U),
µg/l
Na
+
+
K
+
Ca
2+
Mg
2+
3
HCO
2
3
CO
2
4
SO
Cl
-
1
Besaryk
8.46 4.05 5.49 5.76
2.97
0.17
9.76
2.40
16.9 ±
0.8
2
Pervomaika
8.47 4.09 4.99 6.00
2.84
0.17
9.68
2.40
16.8 ±
0.5
ХИМИЯ ЖӘНЕ ХИМИЯЛЫҚ ТЕХНОЛОГИЯ БОЙЫНША IX ХАЛЫҚАРАЛЫҚ БІРІМЖАНОВ СЪЕЗІНІҢ ЕҢБЕКТЕРІ
152
3
Tomenaryk
8.46 3.99 5.39 5.59
2.84
0.17
9.68
2.28
17.3 ±
0.8
4
Aktam
8.33 4.59 5.49 5.02
2.77
0.17
9.68
2.48
16.6 ±
0.6
5
Baigekym
8.22 6.50 4.09 8.06
1.28
0.05
14.14 3.19 14.7 ±0.2
6
Tartogai
8.29 4.28 4.99 5.76
3.00
0.05
9.49
2.48
17.1 ±
0.3
7
Berkazan
8.26 4.32 4.99 5.76
3.08
0.05
9.45
2.48
16.9 ±
1.4
Water of the Syr-Darya river is slightly alkaline (pH ranges from 8.22 to 8.47). The
dominant ions in investigated samples are sulfate and magnesium ions. No any significant
variations of uranium content downstream were observed. The activity сoncentrations of
uranium isotopes are less than normative levels, equal to 3.0, 2.9 and 2.8 Bq kg
-1
for U-238, U-
235 and U-234, respectively. It is necessary to note that the chemical toxicity of uranium is
higher than radiotoxicity. The concentration of uranium is varied from 14.7 to 17.3 µg/l, and as
internationally recommended level for drinking water is equal to 30 µg/l [5], most of
investigated waters can be used for drinking purposes.
According to data of Table 1 and 2, the uranium speciations were calculated and presented
in figure 1.
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
1
2
3
4
5
6
7
[UO2OH]+, %
[UO2(CO3)2(H2O)2]2-, %
[UO2(CO3)3]4-, %
[UO
2
OH]
+
, %
[UO
2
(CO
3
)
2
(H
2
O)
2
]
2-
, %
[UO
2
(CO
3
)
3
]
4-
, %
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