The Water-to-Air Transfer of ³⁵SO₄⁼ by Bursting Bubbles

Abstract

The transfer of ³⁵SO₄ ⁼ from water to air by bursting bubbles was studied as a function of three levels each of three variables in a bubbling solution. The variables were pH, surfactant concentration, and Na³⁵ ₂SO₄ concentration. One combination of the above variables was also studied at three different temperatures. Sterile water solutions containing different combinations of the above factors and a fixed amount of ²²NaCl were bubbled in an enclosure for 1 hour. After bubbling, samples of the aerosol produced, the larger drops that fell out of the air, and the bulk solution were collected and assayed for their ³⁵S and ²²Na content using liquid scintillation counting. The ³⁵S/²²Na enrichment for each droplet sample as compared to the ratio for the bulk solution was determined, and it was found to be dependent upon the combination of the factor levels being bubbled. Both positive and negative enrichments were found, with large positive enrichments being found consistently only for the highest value of surfactant concentration. The temperature study showed no significant enrichment differences for any of the three temperatures studied.

Key Words:

• transfer of sulfate
• transfer by bubbling