SCREENING THE ALKALI-NEUTRALIZED SUNFLOWER SEED OIL BLEACHING ABILITY OF SOME NATURAL AND ACID-ACTIVATED NATURAL CLAYS, SYNTHETIC ADSORBENTS, AND METAL-ORGANIC FRAMEWORKS

The aim of this study was to search vegetable oil bleaching abilities of 30 different adsorbent materials placed into four groups (natural clay, acid-activated natural clay, synthetic adsorbent, metal-organic frames). After oil treatment against control sample, oil color (L, a*, b* values), oil weight loss (%), free fatty acidity (FFA), peroxide value (PV), and the specific extinctions of K232 and K270 were measured. Based on the data analysis, natural montmorillonite, acid-activated halloysite, Dowex, and Ti-MOF were selected, and tested in the same way against two commercial bleaching earth (C.B.E.) samples. Finally, an equal weight portion mixture of the four selected adsorbents were prepared and tested against C.B.Es. Results indicated that acid activated halloysite and Dowex had certain potentials to be implemented in oil bleaching. In conclusion, some other clay modification techniques suggested being applied to those potential adsorbents to improve their bleaching activity for potential commercial applications.