Croatica Chemica Acta, Vol. 91 No. 3, 2018.
Izvorni znanstveni članak
https://doi.org/10.5562/cca3412
Monitoring of the Forced Hydrolysis of FeCl3 Solutions in the Presence of Sodium Dodecyl Sulphate
Mira Ristić
orcid.org/0000-0003-0033-9840
; Ruđer Bošković Institute, Bijenička cesta 54, P.O. Box 180, HR-10002 Zagreb, Croatia
Jasenka Štajdohar
; Ruđer Bošković Institute, Bijenička cesta 54, P.O. Box 180, HR-10002 Zagreb, Croatia
Ivana Mitar
orcid.org/0000-0002-0257-1283
; Faculty of Science, University of Split, Ul. Ruđera Boškovića 33, HR-21000 Split, Croatia
Svetozar Musić
; Ruđer Bošković Institute, Bijenička cesta 54, P.O. Box 180, HR-10002 Zagreb, Croatia
Sažetak
Precipitations by the forced hydrolysis of 0.2 M FeCl3 aqueous solutions between 2 and 72 hours in the presence of 1 % sodium n-dodecyl sulphate (SDS) were investigated. In the absence of SDS a direct phase transformation β FeOOH α-Fe2O3 via dissolution/ recrystallization occurred in the precipitation system. In the presence of SDS small amounts (traces) of α-FeOOH as an intermediate phase precipitated, and with a prolonged time of forced hydrolysis α-FeOOH also transformed to α-Fe2O3 via the dissolution/recrystallization mechanism. On the basis of Mössbauer spectra it was concluded that in the presence of SDS the α-Fe2O3 phase exhibited a lower degree of crystallinity. During the precipitation process in the presence of SDS the competition between the stability of Fe(III)-dodecyl sulphate on one side and the formation of iron oxide phases on the other also played an important role. Thermal field emission scanning electron microscopy (FE SEM) revealed that the big α-Fe2O3 particles possessed a substructure. The elongation of primary α-Fe2O3 particles produced in the presence of SDS was noticed. This effect can be assigned to the preferential adsorption of sulphate groups on nuclei and crystallites of FeOOH and
α-Fe2O3 phases during the forced hydrolysis of FeCl3 solutions.
This work is licensed under a Creative Commons Attribution 4.0 International License.
Ključne riječi
FeCl3 hydrolysis; sodium n-dodecyl sulphate; α-Fe2O3; α-FeOOH; XRD; Mössbauer; FT-IR; FE SEM
Hrčak ID:
213557
URI
Datum izdavanja:
29.12.2018.
Posjeta: 2.044 *