Abstract
The amount of hydrogen ion exchange on the surface of amorphous silica in seawater was measured as a function of pH at 2 and 25°C. Hydrogen ion exchange with the cations present in seawater is pH dependent and at 25°C the fraction of the surface in the cation form increases from 9% at pH 7 to 22% at pH 8. The exchange is temperature dependent and at 2°C and pH 8, 14% of the exchange sites are occupied by cations, as opposed to 22% of the exchange sites at 25°C. These results were used to calculate the buffer capacity of a model sediment consisting of pore water and amorphous silica. For a sediment of 70% porosity, pH 7.7, and 25°C, the buffer capacity of sediment plus pore water is 67 times the buffer capacity of pure seawater.
Original language | English (US) |
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Pages (from-to) | 43-54 |
Number of pages | 12 |
Journal | Marine Chemistry |
Volume | 3 |
Issue number | 1 |
DOIs | |
State | Published - Apr 1975 |
Externally published | Yes |
ASJC Scopus subject areas
- Oceanography
- Chemistry(all)
- Environmental Chemistry
- Water Science and Technology