Doktorska disertacija - Prirodno

Abstract, AB:
Accepted by the Scientific Board on, ASB:
Defended on, DE:
Defended Board, DB: President:
Member:
Member, Mentor:
The properties of each material depend on its chemical composition
and structure, which can only be achieved by precisely defined and
controlled process of materials processing. This dissertation presents
original procedures for obtaining three new porous composite
materials, based on aluminosilicate matrix (bentonite), by
microralloying and certain (hydr)oxides layering. Thus, by obtaining
new materials and examining their interactions with ionic and colloidal
species in the synthetic water, it is achieved a whole new approach to
the removal of Mn 2+ and colloidal MnO2; S 2- and colloidal S and ionic
or colloidal form of Pb(II) from aqueous systems. Therefore, the main
contribution of this dissertation are three new composite materials
denoted as KPM1, KPM2 and KPM3, which have a practical value in
the purification of water from Mn, Pb and S in the ionic and colloidal
state, as well as revealing a number of processes that occur during
synthesis of each composite and in their interaction with ionic and
colloidal species in the water. The structure of composites KPM1 and
KPM2 is specifically arranged and contains crystalline and
amorphous areas, separated by phase boundaries. Electrochemical,
sorption and other characteristics of the composite KPM1 are
manifested in contact with synthetic water containing manganese in
the ionic state (Mn 2+ ) or colloidal manganese (MnO2), leading to
effective removal of both forms of manganese from the water. The
results of research showed that composite KPM2 has defined
electrochemical, chemical and adsorption characteristics, which
provide the oxidation of S 2- ions from synthetic water resulting in
formation of colloidal sulfur that is retained in the porous structure of
composite KPM2. Moreover, chemical bonding to the surface sites of
the composite contributes to the effective S 2- removal. The results of
XRD analysis of composite KPM3 indicate structural changes of
montmorillonite as a basic component of bentonite matrix. Achieved
structural changes contribute to a significant increase in micro- and
mezoporosty of composite, and thus increasing the specific surface
area. The material showed very high sorption activity for ionic and
colloidal species Pb(II).
Образац Q4.09.13 - Издање 1