酰胺醚羧酸盐的分离提纯与表征

Purification and Characterization of Fatty Acid Monoethanolamide Ether Carboxylates

通过无水乙醇热溶抽滤,石油醚重结晶等工序建立了酰胺醚羧酸盐的提纯方法,考察了溶剂用量、结晶温度、结晶时间等对石油醚重结晶效果的影响。结果表明:采用无水乙醇75℃抽滤可有效去除酰胺,石油醚重结晶可有效去除脂肪酸;在m(石油醚)∶m(月桂酸单乙醇酰胺醚羧酸)=20∶1,结晶时间40 m in条件下,55℃结晶两次所得月桂酸单乙醇酰胺醚羧酸产品中和值为132.78 mg NaOH/g,与理论中和值132.28 mg NaOH/g接近;经液相色谱分析,w(月桂酸单乙醇酰胺醚羧酸)≥99.80%。经工艺优化,对C14、C16、C18酰胺醚羧酸盐进行提纯,产物中和值均与理论中和值接近,液相色谱分析产物纯度分别达到99.5%,99.3%,97.5%;并用红外光谱和核磁共振谱对产物结构进行了确认。

A series of fatty acid extracting with hot ethanol and rec monoethanolamide ether carboxylates （AMEC） were purified by rystallizing with petrol ether. The influencing factors, such as the kind and amount of solvent, the temperature and time in recrystallization, were emphatically studied. It was found that alkanol amide can be removed by extracting with ethanol at 75℃and fatty acid can be removed by petrol ether effectively. When the mass ratio of petrol ether to lauric acid single glacollic amide ether carboxylic acid （LAECA） was 20：1, recrystallizing twice at 55 ℃ for 40 min, neutralization value of the purified LAECA was 132.78 mg NaOH/g,very close to the theoretical value （ 132. 29 mg NaOH/g）. The result analyzed by HPLC was w （LAECA） = 99. 80%. AMEC with C14, C16 and C18 chains were purified, too, all the neutralization values were near the theoretical values and the purities analyzed by HPLC were 99. 5% ,99, 3% and 97.5% respectively. The structure of LA.EC was proved by IR and NMR, confirming the high purity of the product and effectiveness of the purification method.