Calcium Carbonate Dissolution from the Laboratory to the Ocean: Kinetics and Mechanism

Area of Science:

• Geochemistry
• Oceanography
• Environmental Science

Background:

• Human-generated carbon dioxide is primarily sequestered through reaction with marine calcium carbonate.
• The calcite dissolution reaction in oceans is globally significant but poorly understood, with conflicting literature findings.
• Previous research may have overlooked the crucial role of mass-transport phenomena.

Purpose of the Study:

• To demonstrate how mass-transport limitations have hindered understanding of calcite dissolution.
• To reconcile conflicting observations in the scientific literature regarding calcite dissolution.
• To provide insights for laboratory experiments and oceanic carbon cycle modeling.

Main Methods:

• Literature review and theoretical analysis of calcite dissolution.
• Examination of mass-transport effects on reaction rates.
• Synthesis of existing experimental and observational data.

Main Results:

• Apparent contradictions in calcite dissolution literature can be explained by unacknowledged mass-transport effects.
• Mass-transport limitations significantly influence the rate and extent of calcite dissolution.
• Understanding these limitations is key to accurate oceanic carbon sequestration predictions.

Conclusions:

• Mass-transport phenomena are critical for accurately describing calcite dissolution in marine environments.
• Future research and modeling of oceanic carbon sequestration must explicitly account for mass-transport.
• Improved understanding will enhance predictions of the ocean's capacity to absorb atmospheric carbon dioxide.