Author(s):
1. Zoran Petrović, Univerzitet u Istočnom Sarajevu.Tehnološki fakultet Zvornik, Republic of Srpska, Bosnia and Herzegovina
2. Jelena Mihajlović, Serbia
3. Tatjana Botić, Faculty of Technology Banja Luka, Republic of Srpska, Bosnia and Herzegovina
4. Pero Dugić, Republic of Srpska, Bosnia and Herzegovina
5. Dragica Lazič, Univerzitet u Istočnom Sarajevu. Tehnološki fakultet Zvornik, Republic of Srpska, Bosnia and Herzegovina
6. Aleksandar Ćebić, Zeeochem doo Zvornik, Republic of Srpska, Bosnia and Herzegovina

Abstract:
Bleaching (decolorization) is a process that separates colored pigments and other undesirable ingredients from raw neutralized vegetable oils (phospholipids, traces of metals, etc.), but it can also lead to a reduction in oxidative stability. For bleaching, commercial activated earths with the addition of activated carbon are usually used, and the parameters depend on the type of oil and the bleaching agent. Laboratory and semi-industrial research into the application of other natural and synthetic materials for bleaching crude vegetable oils is continuously carried out. In this paper, the effects of bleaching of neutralized raw sunflower oil of domestic production with synthetic zeolite type Zeoflair 100 („Alumina“ Zvornik) and imported commercial bleaching earth were investigated. The bleaching process was carried out under laboratory conditions with the following parameters: bleaching temperature 95°C, contact time 30 minutes, mass fraction of the adsorption agent: 0,2% m/m, 1% m/m, 2% m/m and 3% m/m. After bleaching, the sunflower oil is filtered on vacuum filtration equipment. Synthetic zeolite and commercial bleaching earth were characterized by the following methods: XRPD, FTIR, BET, SEM/EDS and particle size distribution. The effects of bleaching were investigated using several methods for the analysis of sunflower oil before and after bleaching, which determined the soap content, peroxide number, color, fatty acid composition (GC), and oil loss. The results of the research showed that the effects of bleaching sunflower oil with zeolite are slightly better in terms of reducing the value of the peroxide number, and weaker in terms of color change than the effects of bleaching with commercial earth and loss of oil. By bleaching sunflower oil with zeolite and commercial earth, there is a slight change in the fatty acid composition of the oil, and the complete removal of soap.

Key words:
bleaching, color, fatty acid composition (GC),peroxide number, sunflower oil, synthetic zeolite

Thematic field:
SYMPOSIUM A - Science of matter, condensed matter and physics of solid states

Date of abstract submission:
01.08.2022.

Conference:
Contemporary Materials 2022 - Savremeni materijali