Publication
Title
Olivine dissolution in seawater : implications for sequestration through enhanced weathering in coastal environments
Author
Abstract
Enhanced weathering of (ultra)basic silicate rocks such as olivine-rich dunite has been proposed as a large-scale climate engineering approach. When implemented in coastal environments, olivine weathering is expected to increase seawater alkalinity, thus resulting in additional CO2 uptake from the atmosphere. However, the mechanisms of marine olivine weathering and its effect on seawatercarbonate chemistry remain poorly understood. Here, we present results from batch reaction experiments, in which forsteritic olivine was subjected to rotational agitation in different seawater media for periods of days to months. Olivine dissolution caused a significant increase in alkalinity of the seawater with a consequent DIC increase due to CO2 invasion, thus confirming viability of the basic concept of enhanced silicate weathering. However, our experiments also identified several important challenges with respect to the detailed quantification of the CO2 sequestration efficiency under field conditions, which include nonstoichiometric dissolution, potential pore water saturation in the seabed, and the potential occurrence of secondary reactions. Before enhanced weathering of olivine in coastal environments can be considered an option for realizing negative CO2 emissions for climate mitigation purposes, these aspects need further experimental assessment.
Language
English
Source (journal)
Environmental science and technology / American Chemical Society. - Easton, Pa
Publication
Easton, Pa : 2017
ISSN
0013-936X [print]
1520-5851 [online]
DOI
10.1021/ACS.EST.6B05942
Volume/pages
51 :7 (2017) , p. 3960-3972
ISI
000398646500042
Full text (Publisher's DOI)
Full text (open access)
UAntwerpen
Faculty/Department
Research group
Publication type
Subject
External links
Web of Science
Record
Identifier
Creation 31.10.2017
Last edited 21.03.2023
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