...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Crystal growth & design >Template-assisted crystallization of sulfates onto calcite: Implications for the prevention of salt damage
【24h】

Template-assisted crystallization of sulfates onto calcite: Implications for the prevention of salt damage

机译：模板辅助硫酸盐在方解石上的结晶：对防止盐分损害的意义

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

In situ X-ray diffraction (XRD) and environmental scanning electron microscope (ESEM) crystallization experiments show oriented growth of magnesium sulfate crystals on a diethylenetriamine-penta-methylene phosphonic acid (DTPMP) template adsorbed onto Iceland spar (calcite, CaCO_3) cleavage surfaces. Epsomite (MgSO_4·7H_2O) and hexahydrite (MgSO_4·6H_2O) crystallize (depending on the ambient conditions) in the presence of DTPMP with (010)_(epsomite)// (101ì...4)_(calcite) and (1ì...11)_(hexahydrite)// (101ì...4)_(calcite), whereas in the absence of DTPMP they show no preferred orientation. On the other hand, sodium sulfate (mirabilite, Na _2SO_4·10H_2O) nucleates onto a Ca-DTPMP precipitate with (001)_(mirabilite)//(101ì...4) _(calcite). In contrast, different sodium sulfate phases crystallize and grow with no preferred crystallographic orientation in the absence of an organic additive. These results allow us to propose a model for the interaction calcite-DTPMP-Na and Mg sulfates based on the template-assisted nucleation and oriented heterogeneous crystallization, mediated by a Ca-precipitate, of inorganic salts on calcitic substrates. This effect results in a (measured) reduction in the critical supersaturation reached by these salts when crystallizing in confined geometries, i.e., a pore, thus resulting in a reduction in crystallization pressure and damage to porous substrates such as building stones. These results have implications in fields where in-pore crystallization of salts results in damage or plugging of the porous network, e.g., cultural heritage conservation and in the oil industry, where phosphonates are used as crystallization inhibitors.
机译：原位X射线衍射（XRD）和环境扫描电子显微镜（ESEM）的结晶实验表明，硫酸镁晶体在吸附在冰岛晶石（方解石，CaCO_3）裂解面上的二亚乙基三胺-五亚甲基膦酸（DTPMP）模板上定向生长。在DTPMP存在下，（0.0101）_（泻岩）//（101ì... 4）_（方解石）和（1ì ... 11）_（六水合物）//（101ì... 4）_（方解石），而在没有DTPMP的情况下，它们没有显示出优选的取向。另一方面，硫酸钠（芒硝，Na _2SO_4·10H_2O）以（001）_（芒硝）//（101ì... 4）_（方解石）形核到Ca-DTPMP沉淀上。相反，在没有有机添加剂的情况下，不同的硫酸钠相结晶并以没有优选的晶体学取向生长。这些结果使我们能够基于钙盐介导的钙盐底物上的钙沉淀介导的模板辅助成核和定向异质结晶，提出方解石-DTPMP-Na与硫酸镁相互作用的模型。当在限定的几何形状即孔中结晶时，这种作用导致这些盐所达到的临界过饱和度的（测得）降低，从而导致结晶压力的降低和对多孔基材例如建筑石材的破坏。这些结果对盐的孔内结晶导致破坏或堵塞多孔网络的领域具有影响，例如文化遗产保护，以及在石油工业中将膦酸酯用作结晶抑制剂。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号