饱水古木材难溶盐分析

Analysis of insoluble salts in waterlogged archaeological wood

为研究饱水古木材中难溶盐的成分和分布,基于电感耦合等离子体光谱、X射线衍射以及显微共聚焦激光拉曼等分析手段对出土出水饱水古木材表面和纵向横向不同取样深度的元素含量和分布、表面凝结物以及纵向横向切面颗粒物的物相进行了分析。分析结果表明饱水古木材含有大量的Fe、S和Ca元素,包含这三种元素的凝结物主要由难溶盐和不溶物组成。难溶盐主要分为两大类,一类为钙盐(包括硫酸盐、碳酸盐和磷酸盐等),一类为硫铁化合物(包括硫铁矿、黄铁矿、磁黄铁矿等);不溶物包括各类铁氧化物(如针铁矿、纤铁矿、赤铁矿和水合氧化铁)以及硫单质等。难溶盐分析结果有助于有针对性地对饱水古木材难溶盐尤其是对古木材危害比较大难溶盐进行预防控制和有效脱除。

In our study, we analyzed the elemental content and distribution on the surface and at different sampling depths longitudinally and transversely, the phases of the sediments on the surface and the particles on the longitudinal and transverse sections of waterlogged archaeological wood, using inductively coupled plasma (ICP) spectrometry, X-ray diffraction (XRD) and micro-confocal laser Raman spectrometry. The results show that waterlogged archaeological wood is rich in the elements, iron (Fe), sulfur (S) and calcium (Ca), and that the sediments containing these three elements are mainly composed of insoluble salts and other insoluble substances. The insoluble salts are mainly divided into two categories, namely, calcium salts (including sulfate, carbonate and phosphate), and iron sulfides (including troilite, pyrite and pyrrhotite). The other insoluble substances include various types of iron oxides (such as goethite, hematite and lepidocrocite, hydrated ferric oxide) and elemental sulfur, etc. The analytical results for these insoluble salts contribute to an understanding of the preventive control and effective removal of insoluble salts on or in waterlogged archaeological wood, especially those seriously harmful to the waterlogged archaeological wood.