乙醇胺类原料形成亚硝胺的比较

A Comparative Study on the Formation of Nitrosamines of Ethanolamines

为了探究目前表面活性剂生产和应用中用脂肪酸甲基单乙醇酰胺或脂肪酸单乙醇酰胺替代脂肪酸二乙醇酰胺的趋势的可行性,本文首先采用亚硝酸叔丁酯法合成3种乙醇胺的亚硝胺化合物作为基准物,通过鉴定产物结构研究亚硝胺的形成历程,然后以亚硝酸法合成亚硝胺化合物,通过生成率比较3种乙醇胺形成亚硝胺化合物的难易程度。亚硝化历程分析结果表明,二乙醇胺或甲基单乙醇胺均直接形成相应的亚硝胺,而单乙醇胺通过歧化反应生成二乙醇胺继而形成少量N-亚硝基二乙醇胺。与二乙醇胺相比,甲基单乙醇胺或单乙醇胺更不易生成亚硝胺,因此用脂肪酸甲基单乙醇酰胺或脂肪酸单乙醇酰胺替代脂肪酸二乙醇酰胺是合理可行的。本研究结果对保障人类生命健康安全具有理论和实践意义。

To investigate the reasonability and feasibility to substitute fatty acid diethanolamide by monoethanolamide and methylethanolamide in surfactant production and application,the nitrosation of methylethanolamine or monoethanolamine was compared with diethanolamine.In this study,nitrosamines were prepared from three ethanolamines by nitrosating agents of both tert-butyl nitrite and nitrous acid.The products of nitrosation by tert-butyl nitrite were identified to reveal nitrosation mechanisms,while the yields of the nitrosamines formed by nitrous acid were used to evaluate the easiness of nitrosation among three ethanolamines.Mechanism analysis of nitrosation shows that diethanolamine or methylethanolamine forms the corresponding nitrosamines,while monoethanolamine solely forms trace amount of N-nitroso-diethanolamine owing to the formation of intermediate diethanolamine by disproportionation of monoethanolamine.The experimental results also reveal that methylethanolamine and monoethanolamine are more difficult to form nitrosamines than diethanolamine.Therefore,it is reasonable and feasible to substitute fatty acid diethanolamide by monoethanolamide and methylethanolamide in surfactant production and application,which has theoretical and practical significance for safeguarding human health and safety.