Browsing by Author "Wścisło, Anna"

Now showing 1 - 3 of 3

Access status: Open Access ,
Halloysite-based material with improved cation sorption properties
(Wydawnictwa AGH, 2012) Wścisło, Anna; Matusik, Jakub
Halloysite is 1:1 layered, dioctahedral phyllosilicate. It belongs to kaolinite subgroup of kaolinite-serpentine group. Halloysite is often defined as a hydrated phase of kaolinite. Two types of this mineral are distinguished: hydrated 10 Å-halloysite, with water molecules in the interlayer space and dehydrated 7 Å-halloysite. Widely conducted research on modified kaolin group minerals, either intercalates or grafted compounds with selected organic molecules opened many possibilities for using this layered aluminosilicate in industry and environmental protection. One of the possible applications is the sorption of heavy metals. For the raw halloysite the sorption exclusively takes place on the particles surface. The interlayer space of the mineral is not accessible for cations. Thus the research goal was to provide the access of cations to the interlayer using organic modifications with selected aminoalcohols (Letaief & Detellier 2007). Moreover, the sorption properties of the new material towards selected cations were examined.
Access status: Restricted ,
Sorpcja kationów metali ciężkich na zmodyfikowanym haloizycie
(Data obrony: 2013-09-19) Wścisło, Anna
Wydział Geologii, Geofizyki i Ochrony Środowiska
The research shows a two-step halloysite modification from ,,Dunino” deposits which leads to a formation of mineral complexes with diethanolamine and triethanolamine and the results of lead, cadmium, zinc and cooper sorption from aqueous solutions on both raw and modified halloysite. The reactions with aminoalcohols were carried out using halloysitedimethyl sulphoxide intercalate as a starting material. The maximum sorption on raw halloysite was equal to 37,17 mmol Pb/kg, 4,42 mmol Cd/kg, 2,67 mmol Zn/kg and 16,16 mmol Cu/kg. The halloysite modification with DEOA and TEOA lead to an increase of the heavy metals sorption capacity and was respectively equal to : Pb - 62 mmol/kg i 57 mmol/kg, Zn - 51 mmol/kg i 46 mmol/kg, Cu - 64 mmol/kg i 74 mmol/kg and Cd - 42 mmol/kg for the both modified materials. The sorption isotherms showed an agreement with Langmuir model. It was observed that the cations sorption increases with pH while the simultaneous nitrate(V) anions sorption decreases. The kinetic data show agreement with pseudo-second order equation and Weber-Morris kinetic model indicated a three-step nature of the sorption process on the modified minerals connected with a migration of cations into its porous structure as well as the interlayer space.
Access status: Restricted ,
Wpływ warunków syntezy na tworzenie się kompleksu kaolinitu z mocznikiem
(Data obrony: 2012-01-09) Wścisło, Anna
Wydział Geologii, Geofizyki i Ochrony Środowiska
Głównym celem badań jest określenie wpływu warunków syntezy na tworzenie się kompleksu kaolinitu z mocznikiem. Odpowiedni czas oraz optymalna temperatura mieszania roztworu mocznika z kaolinitem mogą decydować o jakości interkalatu. Przeprowadzono eksperymenty w różnej temperaturze pobierając próbki w pewnych odstępach czasu. Zbadano otrzymane interkalaty metodami dyfraktometrii rentgenowskiej, spektroskopii atomowej w podczerwieni, analizie CHNS, skaningowej mikroskopii elektronowej i porównano je ze względu na różną temperaturę i czas interkalacji. Ponadto dokonano porównania z warunkami przyjętymi w innych publikacjach, różniącymi się stężeniem mocznika w roztworze, lub sposobem mieszania (ucieranie na sucho).