Abstract
Negative Emission Technologies (NETs) are expected to play a fundamental role in reverting CO₂
levels in the atmosphere to pre-industrial levels. Carbon mineralization, where CO₂ is permanently converted into stable minerals, is an attractive NET, as it inherently prevents CO₂ from leaking back into the environment. Olivine can be used for CO₂ mineralization, as it naturally undergoes chemical weathering. In this dissolution-reprecipitation process, silica and carbonate minerals are the main products. Olivine dissolution, however, is considerably slow and hard to control. A proposed reason for that is the growth of a silica-rich alteration layer, which limits mass transfer at the electrolyte-mineral interface. The properties of this layer are not fully understood, as they are heavily influenced by local concentration and pH gradients.
Confocal Raman Microscopy (CRM) can be used to characterize the alteration layer, as it can both keep track of compositional changes in the mineral, and local pH and concentration gradients in the electrolyte. We observed and tracked the formation of the alteration layer during olivine dissolution in H₂SO₄ over time and at different pH with CRM. A full understanding of the alteration layer properties will provide valuable information on olivine weathering, offering pathways towards more efficient olivine-based mineralization.
levels in the atmosphere to pre-industrial levels. Carbon mineralization, where CO₂ is permanently converted into stable minerals, is an attractive NET, as it inherently prevents CO₂ from leaking back into the environment. Olivine can be used for CO₂ mineralization, as it naturally undergoes chemical weathering. In this dissolution-reprecipitation process, silica and carbonate minerals are the main products. Olivine dissolution, however, is considerably slow and hard to control. A proposed reason for that is the growth of a silica-rich alteration layer, which limits mass transfer at the electrolyte-mineral interface. The properties of this layer are not fully understood, as they are heavily influenced by local concentration and pH gradients.
Confocal Raman Microscopy (CRM) can be used to characterize the alteration layer, as it can both keep track of compositional changes in the mineral, and local pH and concentration gradients in the electrolyte. We observed and tracked the formation of the alteration layer during olivine dissolution in H₂SO₄ over time and at different pH with CRM. A full understanding of the alteration layer properties will provide valuable information on olivine weathering, offering pathways towards more efficient olivine-based mineralization.
| Original language | English |
|---|---|
| Publication status | Published - 20 Aug 2023 |
| Event | IUPAC|Chains 2023 - World Forum , Den Haag , Netherlands Duration: 20 Aug 2023 → 25 Aug 2023 |
Conference
| Conference | IUPAC|Chains 2023 |
|---|---|
| Country/Territory | Netherlands |
| City | Den Haag |
| Period | 20/08/23 → 25/08/23 |
| Other | The conference combines the the 49th IUPAC World Chemistry Congress and the 11th edition of the Dutch Chemistry Conference CHAINS of NWO, and is organized by the Royal Netherlands Chemical Society (KNCV) and NWO |