Page 82 - IJES Special Issues for AIEC2016

72 © Lavrynenko, Chebanov, and Sofronov 2016 | Efficient Extraction of Radioactive Isotopes

establishment of the factors affecting the change control in the case of deviations exceeding 0.1
in the magnetization of Fe3O4 particles in the pH units and adjusted to predetermined values.
deposition from aqueous solutions is an urgent The sorbent was filtered after sorption, and the
task in the development of effective magnetic content of metals in the filtrate was determined.
sorption materials.

Thus, the aim of this work is to determine the
factors that affect the magnetization of the
Fe3O4 particles when precipitation from aque-
ous solutions as well as a comparison between
the sorption properties of magnetic and non-
magnetic Fe2O3 and Fe3O4 particles.

2. Experimental procedure Figure 1: Photomicrographs of particles
annealed at 450°C obtained from nitrate
2.1 Synthesis of Fe2O3 Particles solution: a) at pH 8; b) at pH 9; c) at pH 11.5

Synthesis of Fe2O3 particles is as follows: 100 ml 3. Results and Discussion
of a 0.2M precursor salts of iron (III) in an aque- X-ray analysis of the sample Fe2O3 showed that
ous solution of ammonia or ammonium bicarbo- after annealing at 450°C а-Fe2O3 (hematite) is
nate to a predetermined pH ranging from 7 to formed. Unlike samples Fe2O3 for Fe3O4
12 and stirred on a magnetic stirrer for 30 min.
The resulting precipitate was filtered, washed
several times with distilled water, and dried at
room temperature for 24 h then calcined at
450°C for 1 hour.

2.2 Synthesis of Fe3O4 Particles

Synthesis of Fe3O4 particles was performed by
precipitation from aqueous solution: 5.99 g
FeSO4•7H2O and 10.79 g of FeCl3•6H2O was dis-
solved in 40 ml of distilled water. The resulting
solution was heated to 60°C and 10 ml of 25%
aqueous ammonia solution under constant mag-
netic stirring. The resulting precipitate was
filtered and washed with distilled water. Then
dried in air for 24 hours.

2.3 The Sorption Properties

Sorption is carried out in mono-component
heavy metal solution at pH 6.5 with concen-
tration of 10–250 mg/l. In a 100 ml beaker the
50 ml of model solution was adjusted by
addition of nitric acid or aqueous ammonia
solution to a predetermined pH 6.5. Solution pH
was measured by the "150 pH" pH-meter with
glass electrode ESL-63-07 and the auxiliary
silver chloride electrode EVL1MZ then was
added to 0.1 g of the adsorbent and kept under
stirring for 40 minutes. The process of sorption
was performed every 10 minutes with pH

Science Target Inc. www.sciencetarget.com