Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article Assessment of the Repeatability of Column Experiments Results on the Example of a Conservative Tracer(Sciendo, 2025) Pietrzak, Damian; Kania, Jaroslaw; Kmiecik, Ewa; Baba, AlperMost studies on the behavior of pollutants in the groundwater environment are carried out in laboratories, and the results are then implemented at local and regional levels using model simulations or analytical solutions. Column experiments are used to determine the transport characteristics of inorganic and organic chemicals in the soil and water environment. Although column experiments have been conducted regularly for many years, there is currently no established standard protocol for setting up and conducting them to ensure consistent results. The repeatability of column experiments was evaluated for soils, which differ primarily in the silt and clay content, using a conservative tracer susceptible only to advection and dispersion processes to reduce the number of variables affecting the results of the study which arise in a case of using reactive contaminants. The column experiments performed according to the adopted methodology are characterized by high repeatability of the obtained test results for the transport parameters, regardless of the type of injection or the chosen column length (only a small-scale effect is visible). Based on the results, it can be noticed that for the same soil the values of the pore-water velocity for different types of injections and column lengths are very similar. The percentage difference between the values of pore-water velocity obtained for both tested soils does not exceed 5% and for individual pairs of parallel column experiments it does not exceed 3%.Article Citation - WoS: 19Citation - Scopus: 21Kinetic and Thermodynamic Investigations of Strontium Ions Retention by Natural Kaolinite and Clinoptilolite Minerals(Walter De Gruyter Gmbh, 2005) Akar, Dilek; Shahwan, Talal; Eroğlu, Ahmet EminThe current study was devoted to the determination of various thermodynamic and kinetic parameters resulting from the fixation of Sr2+ by natural samples of kaolinite and clinoptilolite minerals. The sorption process followed pseudo second order kinetics, with faster sorption on kaolinite compared to clinoptilolite, where the uptake is affected by intraparticle diffusion. Freundlich and Dubinin-Radushkevich isotherm models described the data more adequately than Langmuir model, and clinoptilolite showed a higher strontium sorption capacity than kaolinite. Thermodynamically, the activation energy of Sr2+ sorption by kaolinite and clinoptilolite were respectively, -8.5 and -18.4 kJ/mol. The sorption process on both minerals was spontaneous and endothermic at all the studied concentrations, with ΔH° being 11.3 and 9.8 kJ/mol, for sorption on kaolinite and clinoptilolite, respectively. The findings of this study were compared with those of an earlier study on the uptake of Cs+ by the same minerals.Article Citation - WoS: 14Citation - Scopus: 15Chitosan-Immobilized Pumice for the Removal of As(v) From Waters(Springer Verlag, 2014) Turan, Dilek; Kocahakimoğlu, Cemre; Boyacı, Ezel; Sofuoğlu, Sait Cemil; Eroğlu, Ahmet EminA novel sorbent, chitosan-immobilized pumice, has been prepared for the sorption of As(V) from waters prior to its determination by hydride generation atomic absorption spectrometry. The success of the immobilization has been checked with such characterization techniques as scanning electron microscopy, thermal gravimetric analysis, and elemental analysis. Points of zero charge of the sorbents were determined with potentiometric mass titration. Batch-type equilibration studies have shown that the novel sorbent can be employed at a wide pH range resulting in quantitative sorption (>90 %) at pH 3.0-7.0 and greater than 70 % sorption at pH >8.0. These results demonstrate the advantage of immobilizing chitosan onto pumice, because, under the same conditions, pumice displays <20 % sorption toward As(V), whereas chitosan gives approximately 90%sorption only at pH 3.0. The validity of the method was verified through the analysis of ultrapure, bottled drinking, and tap water samples spiked with arsenate; the respective sorption percentages of 93.2 (±0.7), 89.0 (±1.0), and 80.9 (±1.3) were obtained by batch-type equilibration. Arsenic sorption was also examined in the presence of common interfering ions resulting in competing effects of PO3- 4 and NO- 3on As(V) adsorption.