サフラワー油の脱水過程でモレキュラーシーブから溶出した微量金属元素の放射化分析

抄録

Dissolved water in safflower oil affects the autoxidation of this oil significantly. Molecular sieves were used to remove the dissolved water from the oil. This method is much simpler than that of distillation, and dissolved water can be removed to the same extent as that by distillation. But, due to the elution of many kinds of trace metallic elements in the oil dehydrated with molecular sieves, these elements were analyzed by neutron activation analysis. For a data comparision trace amounts of metallic elements in the oil dehydrated by distillation were also analyzed.
Since the intensity of the γ ray-photoelectric peak of nuclide ²⁸Al was largest among the detected elements, this element was analyzed quantitatively and the other elements qualitatively.
In safflower oil dehydrated with molecular sieves, 14 kinds of the elements (I, Br, Al, Mg, Si, V, Cl, Nd, Ta, Cr, Sb, Cs, Co, Na) were detected. Also, I, Br, Cl, Cr, Ta, Sb, and Al elements were detected in the oil dehydrated by distillation. The intensity of the photoelectric peak of nuclide except ²⁸Al was essentially the same as that in the oil dehydrated by distillation, but the intensity of ²⁸Al in the oil with molecular sieves was about 28 times stronger than that in distillation oil. In the molecular sieves, 19 impure elements in addition to the original constituents (Na, K, Al, Si, O) were detected. It was Al, Na, Si, Nd, Cs, and Co along with impure elements may possibly have been eluted in the oil.
Al element in saffolwer oil dehydrated with molecular sieves was analyzed quantitatively. 0.91 ppm of Al was detected in safflower oil. The eluted amount of Al in safflower oil dehydrated by distillation was 0.032 ppm. A larger amount of Al element was thus eluted into the oil dehydrated with molecular sieves than by distillation.