在热液体水中确定热石稳定性的因素
Lu Zhang1,2, Kuizhi Chen3,2, Banghao Chen4
1School of Chemical, Biological and Materials Engineering, University of Oklahoma , 100 East Boyd Street, Norman, Oklahoma 73019, United States.
Journal of the American Chemical Society
|August 25, 2015
概括
在热水中由于西兰醇缺陷而降解. 处理这些缺陷可以提高化物在水相过程中的稳定性,从而改善它们在生物质转化中的使用.
科学领域:
- 材料科学
- 催化剂
- 化学工程
背景情况:
- 热石易受热液体水的影响,限制其在生物质转化等水相过程中的使用.
- 像布伦斯特德酸位点和西兰醇缺陷这样的水友性部分会影响石与水的相互作用,但它们在水的敏感性方面的具体作用尚不清楚.
研究的目的:
- 系统地调查不同分量对热液体水的敏感性的作用.
- 在水环境中确定导致化石降解的主要因素.
主要方法:
- 在200°C暴露在水中后,对具有不同特征的HY,H-ZSM-5和H-β化石的结晶性损失进行比较 (Si/Al比率,布伦斯特德酸位,结构,化物缺陷).
- 与有机酸一起功能化的酸缺陷,以评估对疏水性和稳定性的影响.
主要成果:
- 醇缺陷的密度被明确地确定为影响热液水对石敏感性的最关键因素.
- 醇缺陷的功能化显著增加了热的疏水性和对热液体水的增强耐受性.
结论:
- 醇缺陷是热液水中热石不稳定的主要原因.
- 修改西兰醇缺陷为水相应用 (如生物质升级) 提高焦化物稳定性提供了一种可行的策略.
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