Трансестерифікація рослинних олій бутан-1-олом у присутності гетерогенних каталізаторів

The transesterification of sunflower and rapeseed oil triglycerides by butan-1-ol in the presence of cation exchange resin KU-2-8 with immobilized metal ions Cu2+, Ni2+, Co2+ and Sn2+ has been studied. It was used untreated cation exchange resin KU-2-8 and cation exchange resin KU-2-8 treated by an excess of 0.1 M sodium hydroxide solution for 90 min or 7 days as the catalyst. The treatment duration of the catalyst by an alkali solution significantly affects on the initial rate of the transesterification reaction and on the triglycerides conversion for 240 minutes. It was shown that prolonged treatment by sodium hydroxide solution (for 7 days) leads to a decrease the initial rate of the transesterification reaction. The treatment also significant decrease the triglycerides conversion for 240 min of reaction. It was found that the initial rate of transesterification reaction decreases on 12% by treatment a cation exchange resin with immobilized Cu2+ or Sn2+ ions, and the initial rate of transesterification reaction simultaneouslydecreases on 3.5 times by treatment a cation exchange resin with immobilized Ni2+ ions. The conversion of sunflower oil triglycerides in the presence of catalysts treated by an alkali solution is 8–34% lower than in the presence of untreated catalysts. It was shown that treatment of cation exchange resin with immobilized Cu2+ or Ni2+ ions by alkali solution for 90 min allows to increase the initial reaction rate and the triglycerides conversion for 240 min. It was found that conversion of sunflower oil triglycerides for 240 min at a molar ratio of butan-1-ol : triglycerides of 15 : 1 reaches 82.7 and 87.0 % in the presence of treated cation exchange resin KU-2-8 with immobilized Cu2+ and Ni2+ ions, respectively, and the conversion of rapeseed oil triglycerides under the same conditions in the presence of cation exchange resin KU-2-8 with immobilized Cu2+ ions reaches 79.0%. It was made an assumption that treatment of cation exchange resin by alkali solution affects on the electron density of the metal cation immobilized on the cation exchange resin KU-2-8 due to the OH– groups coordination on the metal cation. It was concluded that treatment of cation exchange resin with immobilized metal ions by the alkali solution is an effective way to increase its catalytic activity in the transesterification reaction of vegetable oils triglycerides.