Removal of impurities with nano-pores aerogel from sunflower oil

Aerogel is a porous and lightweight material and is classifed as 'nanomaterial' which has been working in recent years due to its superior physical properties. Aerogel is commonly used as a termal and sound insulation material, padding for varnishes and paint, adsorbent in chemical sector, catalyst carrier, injection agent, catalyst support, adsorbent of toxic organic compounds. Silica aerogel is nanomaterials which consists of lots of air filled pores with a crosslinked silica chains (SiO2) in their internal structure and their pore size vary between 5-100 nm. Aerogel is known to be an effective adsorbent in adsorption of hydrogen sulfide and sulfur dioxide and various solvents. Also they have been shown to be effective in adsorption of various heavy metals in water. Refining processes generally are applied in edible oil production such as degumming, neutralization, bleaching and deodorization. Impurities such as fatty acids, phospholipids, heavy metal, peroxide which are present in the oil are removed in these stages. Impurities removed with degumming stage are phospholipids and trace metals, from neutralization stage are free fatty acids and phospholipids, from bleaching stage are color pigment and soap phase, from deodorization stage are aldehyde, ketones which makes oil smell bad, free fatty acid and PAH. Bleaching earth and silica+bleaching earth combinations are used during bleaching stage in the oil industry. Because of the adsorption capacity of aerogel has been well, adsorption of impurities in the sunflower oil has been chosen for the first time in this study. The effectiveness of it in various refining stages were examined. For this reason, adsorption studies have been performed in a duration of 30 minutes with a combination of sunflower oil in a ratio of 0,5-3% in weight of silica aerogel, bentonite, trisyl, bentonite+aerogel and bentonite+trisyl in 90°C. For acidification, the best result was observed when aerogel was used in a ratio of 1-3%. When aerogel was used in a ratio of 3%, free fatty acids have been seem to eliminated in a ratio of 31,78%. The best result has been observed with trisyl for the removal of peroxides. Phosphorus in raw oil has been eliminated with aerogel and trisyl. In bleaching process, which has been applied to neutralized oil, the mixture of 1% bentonite+aerogel gave the most effective results. Keywords: Aerogel, adsorption, edible oil refining, neutralization, bleaching