在碳矿化过程中,结构无形和晶体酸盐中酸盐协调的演变
Xun Gao1, Prince Ochonma2, Divya Prasad1
1School of Civil and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA. gg464@cornell.edu.
Physical chemistry chemical physics : PCCP
|March 12, 2025
概括
利用地球上丰富的酸进行碳矿化是巨级碳储存的关键. 这项研究揭示了结构特征如何影响反应性,通过二碳酸提高碳矿化率高达19.5%.
科学领域:
- 材料科学 材料科学 材料科学
- 地质化学 地质化学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 可扩展的碳储存需要了解酸对碳矿化反应的活性.
- 目前的知识将结构特征与无形和晶体酸盐的反应性联系起来是有限的.
- 制定有效的碳矿化策略对于减缓气候变化至关重要.
研究的目的:
- 研究二氧化协调和质量转移对碳矿物化的影响.
- 合成和表征无形和晶体酸盐 (AC Mg-酸盐).
- 将AC Mg-酸盐的碳矿化行为与高度结晶的Mg-酸盐 (HC Mg-酸盐) 进行比较.
主要方法:
- 从合体前体合成ACMg-酸盐.
- 操作超小/小/广角X射线散射 (USAXS/SAXS/WAXS) 用于结构分析.
- 在200°C和20 atmCO2的碳矿化实验中,在含/不含NaHCO3.3的水溶液中进行碳矿化实验.
主要成果:
- 在AC Mg-酸盐合成过程中的结构和形态过渡被描绘出来.
- 在AC和HCMg-酸盐中,NaHCO3的存在增加了13.3-19.5%的碳矿化.
- 在NaHCO3中增强的矿化归因于缓冲,促进酸盐溶解和碳酸盐形成 (MgSiO3和SiO2来自Mg2SiO4).
结论:
- 设计的酸盐前体可以解锁酸盐转化,以实现高效的碳矿化.
- 这种方法显示了将碳矿化与可持续气生产途径相结合的可行性.
- 了解结构-反应性关系对于推进持久碳储存解决方案至关重要.
相关概念视频
02:42Ionic Crystal Structures
14.0K
Ionic crystals consist of two or more different kinds of ions that usually have different sizes. The packing of these ions into a crystal structure is more complex than the packing of metal atoms that are the same size.
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
14.0K
01:24Hydration of Cement
185
Hydration of cement is a chemical reaction between cement particles and water. This process occurs primarily through two mechanisms: through-solution and topochemical. In the through-solution process, anhydrous compounds dissolve into their constituents, hydrates form in the solution, and then precipitate from the supersaturated solution. The topochemical process involves solid-state reactions at the cement particle surface. The through-solution process dominates the topochemical process at the...
185
02:34Structural Isomerism
19.1K
Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can...
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can...
19.1K
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
41.1K
Tetrahedral Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
41.1K
01:23Properties of Organometallic Compounds
921
Organometallic compounds are compounds that contain a carbon–metal bond. Carbon belongs to an organyl group like alkyl, aryl, allyl, or benzyl groups. The metal can be from Group I or Group II of the periodic table, a transition metal, or a semimetal.
921
01:26Alkali Aggregate Reaction in Concrete
82
The alkali-aggregate reaction in concrete involves natural siliceous minerals in aggregates reacting with alkaline hydroxides derived from cement alkalis. This reaction forms an alkali-silica gel that absorbs water, swells, and increases in volume, which is confined by the surrounding cement paste, creating internal pressures that crack and disrupt the concrete. The extent of expansion and damage can be partly attributed to the alkali-silica reaction's osmotic hydraulic pressure and the...
82