重庆三峡地区考古出土铁器的脱盐保护

Desalting Protection of Iron Artifacts Unearthed in the Three Gorges Area of Chongqing

针对重庆三峡地区考古出土的一批汉代铁器,采用扫描电镜、能谱仪和X射线衍射仪,分析了该批铁器的锈蚀产物形貌和成分,并采用氯离子选择电极对铁器在去离子水和添加0.5 mol/LNaOH的去离子水溶液中的脱盐过程进行了动态监测。结果表明:该批铁器锈蚀产物主要由α-FeOOH、Fe_(3)O_(4)、SiO_(2)和NaAlSi_(3)O_(8)等组成,部分铁器含有少量氯元素;在去离子水和含0.5 mol/L NaOH去离子水溶液中,浸泡约150 h后溶液中的氯离子含量随时间的继续延长无明显变化,基本低于2 mg/L,脱盐周期远远低于其他含氯量高的铁器(海洋出土铁器)。

The morphology and composition of the corrosion products of a batch of Han Dynasty iron artifacts unearthed in the Three Gorges area of Chongqing were analyzed by scanning electron microscopy,energy dispersive spectrometer and X-ray diffractometer.The desalination process of iron artifacts in deionized water and deionized water solution with 0.5 mol/L NaOH was dynamically monitored by chloride ion selective electrode.The results showed that the corrosion products of the iron artifacts were mainly composed of α-FeOOH,Fe_(3)O_(4),SiO_(2),NaAlSi_3O_8,and some iron artifacts contained a small amount of chlorine.In deionized water and deionized water solution containing 0.5 mol/L NaOH,after soaking for about 150 h,the chloride ion content in the solution did not change significantly with the extension of time,basically lower than 2 mg/L,and the desalination cycle was much lower than other iron artifacts with high chloride content(iron artifacts unearthed from the sea).