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The adsorption of a cationic dye, Basic Blue 16 (BB16), by montmorillonitic clay was studied in detail. Changes in the molecular structure during adsorption were analyzed by FTIR spectroscopy. BB16 adsorption onto the clay mainly results from hydrogen bonding between OH and NH 2 groups of dye molecules and OH groups of clay and electrostatic interaction between the negatively charged clay surface and cationic dye. The montmorillonitic clay dose had an inverse effect on the adsorption performance, while the highest dye removal was 305 mg/g at pH 3.6. An increase in temperature and dye concentration positively enhanced the adsorption capacity of the montmorillonitic clay. Temperature had no effect on the adsorption at a dye concentration less than 500 mg/L, while dye adsorption was positively enhanced at elevated dye concentrations. Three-parameter equations provided higher better fitting than two-parameter equations while the Freundlich model had the highest correlation coefficient and the lowest error values with experimental data. The BB16 adsorption was well followed by pseudo-second order model and the rate of adsorption process was controlled by surface and intraparticle diffusion. Thermodynamic evaluations revealed that the adsorption process was spontaneous and endothermic, while the randomness increased during adsorption. Experimental results indicate that montmorillonitic clay from Eskisehir is a promising adsorbent for the removal of cationic dye molecules from aqueous solutions.

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Nowadays, parallel to the increasing use of nuclear technology, radiation protection becomes an important issue. The use of materials, such as (Pb) lead, has become standard for protection from radiation. Improving the radiation attenuation properties of new types of materials has become more essential. In this study, the shielding properties of panels containing boron (B) waste (borogypsum) that were produced with different iron (Fe) mineral additives were studied. The attenuation properties of two types of panels produced by using magnetite and borogypsum against gamma radiation were investigated. It was found that gamma radiation protection decreases as the borogypsum contribution to the magnetite panel mixture increases. At the same time, it was observed that the linear attenuation coefficient and water absorption decrease due to the increase in borogypsum additive and sintering temperature inside the panels.