Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
Browse
2 results
Search Results
Now showing 1 - 2 of 2
Article Citation - WoS: 69Citation - Scopus: 77Morphosynthesis of Caco3 at Different Reaction Temperatures and the Effects of Pdda, Ctab, and Edta on the Particle Morphology and Polymorph Stability(Elsevier Ltd., 2007) Altay, E.; Shahwan, Talal; Tanoğlu, MetinFacile precipitation of CaCO3 was performed using aqueous solutions of CaCl2 with Na2CO3 over a wide range of mixing and aging temperatures. The precipitation process was then repeated in the presence of PDDA, CTAB, and EDTA at the mixing temperatures of 30 °C, 50 °C, 70 °C, and 90 °C. The presence of these additives was seen to greatly suppress the formation of aragonite. Among these additives, EDTA was the one that showed the most prominent effects on particle morphology of CaCO3. The sequence of pH adjustment appeared to be a critical factor for the additive functionality.Article Citation - WoS: 43Citation - Scopus: 47Aas, Xrpd, Sem/Eds, and Ftir Characterization of Zn2+ Retention by Calcite, Calcite–kaolinite, and Calcite–clinoptilolite Minerals(Elsevier Ltd., 2005) Shahwan, Talal; Zünbül, Banu; Tunusoğlu, Özge; Eroğlu, Ahmet EminIn this study, the sorption behavior of Zn2+ on calcite, kaolinite, and clinoptilolite, in addition to mixtures of calcite with kaolinite and clinoptilolite, was investigated at various loadings and mixture compositions using atomic absorption spectroscopy, scanning electron microscopy/energy dispersive X-ray spectroscopy, X-ray powder diffraction, and Fourier transform infrared techniques. According to the obtained results, within the experimental operating conditions, the sorption capacity was enhanced with increasing amount of calcite in both types of mixtures. Under neutral–alkaline pH conditions and high loadings, the order of Zn2+ retention was observed as calcite > clinoptilolite > kaolinite. The experiments on the retention of Zn2+ by pure calcite under conditions of oversaturation showed that the uptake process proceeds via an initial adsorption mechanism (possibly ion-exchange type) followed by a slower mechanism that leads to the overgrowth of the hydrozincite phase, Zn5(OH)6(CO3)2.
