چكيده به لاتين
In this research, Ti3C2Tx MXene was studied as a nanolayer adsorbent for the absorption of
thorium, strontium, cesium and magnesium ions. in the last few decades, the use of nuclear
energy has introduced huge amounts of heavy and toxic metals into the environment. Among
the various technologies, surface absorption has been of interest for removing heavy metals
from the environment with features such as simplicity of the process, non-degradation of the
environment, and cost-effectiveness. The slow kinetics, low efficiency and relatively poor
selectivity of the used adsorbents have drawn the attention of researchers to the development
of efficient and selective adsorbents. Therefore, maxins with unique characteristics such as
hydrophilic nature, effective specific surface area, presence of surface functional groups,
excellent mechanical and chemical stability in absorbing heavy metals have been considered.
In this research, titanium-based Maxine is used in investigating the absorption process of
thorium, strontium, cesium, and magnesium due to the abundance of the element, the absence
of production of toxic products during synthesis, and the widespread presence of surface
functional groups after synthesis. The structure and morphology of maxin synthesized with
both conventional methods of 40% HF and HF in situ (12M LiF/9M HCl) using
characterization tests such as XRD, SEM, EDS, FTIR, BET, XRF, zeta potential and TGA
have been investigated. The difference in the abundance of surface functional groups formed
and the interlayer distance by the synthesis method leads to the difference in the absorption
capacity of each of the heavy metals with maxin. To investigate the effect of each of the unique
characteristics of MXenes, such as the specific surface area, the type and abundance of surface
functional groups, and the adjustable interlayer distance of MXenes, the MXene adsorption
capacity of each heavy metal with modified MXenes. It was investigated with potassium
dihydrogen phosphate and chitosan. The MXene adsorption capacity modified with potassium
dihydrogen phosphate has increased two-fold by increasing the distance between the layers. In
addition to increasing the surface functional groups in favor of adsorption, it is possible to
provide a suitable space for the interactions of electrostatic forces as much as possible, and as
a result, adsorption increases. To select the optimal operational and structural conditions of the
adsorber, the RSM-CCD were used. The thermodynamic results show that adsorption with
maxin (pristine and modified) is endothermic and spontaneous and is associated with an
increase in disorder. In addition to thorium, these results can also be interpreted for strontium
and cesium with the Freundlich isotherm model and for magnesium with Langmuir. MXene
Reduction was done in 4 steps by 0.1 M hydrochloric acid and the results of up to 4 steps of
reduction and desorption show nearly 85% adsorption of the first step. Structural analyzes show
that the structure of maxin has not changed after adsorption-desorption.
