文物中蜡类材料的热裂解-气相色谱/质谱识别  

Identification of waxes using pyrolysis-gas chromatography/mass spectrometry

作　　者：王娜 谷岸[1] 刘恺 李敬源[1] 雷勇[1] WANG Na;GU An;LIU Kai;LI Jingyuan;LEI Yong(The Palace Museum, Beijing 100009, China)

机构地区：[1]故宫博物院,北京100009

出　　处：《文物保护与考古科学》2020年第6期71-77,共7页Sciences of Conservation and Archaeology

摘　　要：为识别文物中蜡质原材料,以及文物保护修复工作中常用蜡类材料的类别,研究通过在线甲基化热裂解-气相色谱/质谱联用技术对蜂蜡、棕榈蜡、小烛树蜡、地蜡、石蜡等蜡类材料进行分析检测。研究发现:蜂蜡的主要裂解产物为直链烷烃、直链脂肪酸、直链醇、含羟基脂肪酸;棕榈蜡为直链醇、直链脂肪酸、脂肪酸衍生物;小烛树蜡为直链烷烃、直链脂肪酸、直链醇、羽扇豆醇及其衍生物、计曼尼醇及其衍生物、脂肪酸衍生物;地蜡、石蜡等矿物蜡的主要裂解产物为直链烷烃。不同蜡中裂解产物的种类及其相对含量分布规律均有所区别,因此通过在线甲基化热裂解-气相色谱/质谱联用技术可以实现不同种类蜡的区分。通过所建立的方法及总结的数据,研究推断故宫旧藏清代紫檀木边座嵌玉人鸂鶒木山水图插屏中镶嵌珐琅构件所用棕色蜡为蜂蜡,所用白色蜡为矿物蜡及少量蜂蜡。本研究所建立方法易于推广,适用于文物中蜡类材料的准确、快速识别。In order to distinguish waxes used in cultural relics and used as conservation or restoration materials for cultural relics,online-methylation pyrolysis-gas chromatography/mass spectrometry(Py-GC/MS)was applied to analyze beeswax,carnauba wax,candelilla wax,ozokerite and paraffin wax.It is found that 1)the main pyrolytic products of beeswax are straight-chain alkanes,straight-chain fatty acids,straight-chain alcohols and fatty acids with hydroxyl groups;2)those of carnauba wax are straight-chain alcohols,straight-chain fatty acids and fatty acid derivatives;3)those of candelilla wax are straight-chain alkanes,straight-chain fatty acids,straight-chain alcohols,lupeol and its derivatives,germanicol and its derivatives and fatty acid derivatives;4)those of ozokerite and paraffin wax—mineral waxes—are both straight-chain alkanes.Different waxes could be distinguished since the kinds and relative contents of pyrolytic products in each wax are different.The established Py-GC/MS procedure and summarized data were successfully applied to the identification of beeswax and mineral wax used for the inlaying enamel in a Qing table screen with a rosewood frame,inlaid jade figures and a wengewood carved landscape collected in the Forbidden City.The method of our present work is easy for the spreading and applicable to the accurate and rapid identification of waxes used in cultural relics.

关 键 词：热裂解-气相色谱/质谱 蜂蜡 棕榈蜡 小烛树蜡 地蜡 石蜡 

分 类 号：K876.9[历史地理—考古学及博物馆学]