恐龙化石的人工加速腐蚀研究

On Artificial Accelerated Corrosion of Dinosaur Fossils

为了深入探讨恐龙化石的风化原因,为恐龙化石新型保护材料的研制提供理论支持,项目采用0.5,1,2mol/L硫酸溶液,二氧化碳饱和液与5%碳酸氢钠溶液对自贡出土恐龙化石进行人工加速腐蚀实验;利用失重法、XRD、XRF和显微法表征.结果表明:3种介质对化石腐蚀速率依次为硫酸溶液24.213 6g/(m2·h),二氧化碳0.663 7g/(m2·h),碳酸氢钠0.126 3g/(m2·h).硫酸溶液对化石腐蚀速率是二氧化碳的36.5倍,是碳酸氢钠溶液的191.7倍;在0.5mol/L硫酸溶液腐蚀下,XRD和XRF说明化石中CaCO3首先腐蚀,腐蚀量最大,腐蚀后化石中钙含量减少66.4%.化石腐蚀前后形貌变化与腐蚀速率一致.

To understand the mechanism of dinosaur fossils′weathering,the corrosion of the dinosaur fossils unearthed in Zigong have been investigated in this paper.Its artificial acceleration corrosion were investigated in 0.5mol/L,1mol/L,2mol/L sulfuric acid solution,saturated carbon dioxide solution and5%sodium hydrogen carbonate solution,respectively.Conducted in the fossils corroded have been characterized by XRD,XRF and microscopic method.The results show that the corrosion rates of the fossils these three media are 24.213 6g/（m2·h）for sulfuric acid solution,0.6637g/（m2·h）for carbon dioxide and 0.126 3g/（m2·h）for sodium hydrogen carbonate.The corrosion rate in sulfuric acid solution is 36.5and 191.7times as great as those of carbon dioxide and sodium hydrogen carbonate,respectively.In the case of 0.5mol/L sulfuric acid solution,the results from XRD and XRF demonstrate that CaCO3in fossils is corroded firstly.The corrosion degree of CaCO3is very large.The calcium content is reduced by 66.4%after corrosion.The morphology change of fossils uncorroded and corroded is consistent with the corrosion rates.