ガスクロマトグラフィーによる木ロウ中の脂肪酸成分の研究
スポンサーリンク
概要
- 論文の詳細を見る
It has already been reported that Japan wax contains higher dibasic acids such as docosanedioic and eicosanedioic acids, but no detailed reports including the lower dibasic acids have been found yet.<BR>The purpose of this investigation is to determine accurately the fatty acid and dibasic acid compositions of the wax by gas-liquid chromatography using a hydrogen flame ionization detector.<BR>Gas chromatographic analyses were performed on a gas chromatograph of Shimadzu GC-1 B type equipped with a flame ionization detector. U-shaped stainless steel columns of 150cm×4mm i.d., and another 75cm×4mm i.d. for the specified analysis of higher dibasic acid dimethyl esters, were packed with 10% polyethyleneglycol adipate on Diabase B (Kotaki-seisakusho Co., Ltd.), 80-100 mesh. The flow rates of helium as the carrier gas, hydrogen and air for the detector were approx. 60m<I>l</I>/min, 40m<I>l</I>/min and 1.0<I>l</I>/min, respectively. The inlet heater was kept at 280°C, the column temperature was at 215°C for the analysis of fatty acid methyl esters and lower dibasic acid dimethyl esters, and at 220°C for the long-chain dibasic acid dimethyl esters.<BR>As a result, different dibasic acids (C<SUB>5</SUB>, C<SUB>6</SUB>, C<SUB>7</SUB>, C<SUB>8</SUB>, C<SUB>9</SUB>, C<SUB>10</SUB>, C<SUB>11</SUB>, C<SUB>12</SUB>, C<SUB>14</SUB>, C<SUB>16</SUB>, C<SUB>18</SUB>, C<SUB>20</SUB> and C<SUB>22</SUB>), various fatty acids (less than C<SUB>10</SUB>, C<SUB>14</SUB>, C<SUB>15</SUB>, C<SUB>16</SUB>, C<SUB>17</SUB> C<SUB>18</SUB>, C<SUB>20</SUB> and C<SUB>22</SUB>) and considerable amounts of unknown materials were found in the free acids responsible for the high acid value (21.5) of the wax.<BR>In addition, the methyl esters, obtained by direct methanolysis of the wax and subsequent removal of the free acids, contained small amounts of C<SUB>14</SUB>-, C<SUB>16</SUB>-, and C<SUB>18</SUB>- as well as C<SUB>20</SUB>- and C<SUB>22</SUB>- dibasic acids.<BR>The thin-layer chromatography on silica gel was also applied to the analysis of the wax; namely, it was observed that the dibasic acids were separable from the fatty acids and other materials and that each constituent can be examined in detail.
- 日本油化学会の論文