Figure 5 Results of AG2-X8 resin elution with 4 M KCl elution.
Related Figures (8)
Fig. 1 A: Schematic of resin column; B: picture. All laboratory and field samples were collected in 5-60 ml sterile plastic syringes and pressed through a 0.45 um syringe filter before passing the solution through the prepared exchange resin columns. To improve the interaction between the sample ion and resin, the flow rate did not exceed 3 mL min ' (which can be measured by timing how fast a graduated cylinder or falcon tube is filled). In preliminary lab experiments we found that at higher flow rates the sample ions are not always fully retained, presumably due to the shorter contact time. The volume of each sample was carefully measured by Table 1 Relevant selectivities of anion exhange resins used in this study Table 2 Stability of polythionate and thiosulfate in samples from Cinder Pool, YNP Fig. 3 Effect of addition of Cd on thiosulfate concentration. Test conducted at Ojo Caliente, YNP. 0.5 mL 0.5 M Cd acetate was added to 60 mL sample. Analysis were conducted on site using a mobile lab parked next to the spring. Fig. 4 Recovery of sulfate and thiosulfate from a synthetic solution loaded on AGI-X8 resin column as a function of eluent (KCI) concentration. “ Thiosulfate standards have pH > 7. In the field KCN was added to the samples to convert polythionates to SCN using cyanolysis.’’ Hence, this test pertains to the stability of SCN” over time as a measure of polythionate concentration and the formation of additional polythionate over time, which would be converted to SCN” in the bottle. Fig. 6 Comparison of results for three techniques used for thiosulfate analyses for five thermal springs in the Norris Geyser Basin at Yellowstone National Park in September, 1998. The AG2-X8 resin also was used at Green Lake, a meromictic glacial lake located at Green Lake State Park in Fayetteville, New York during the summer of 1998. Green Lake is a stratified lake, with a chemocline at about 20 meters depth. The Table 3 Results from Green Lake, Fayetteville, NY chemocline separates an aerated surface water layer from a deep anoxic water layer. A | m thick transition at the chemo- cline supports a pink microbial community”® and contains up to 22 wmol L™! thiosulfate (Table 3). Using a depth sampler, water was brought up from above, below, and within this transition layer. Each sample was loaded onto an AG2-X8 resin column, taken back to SUNY-Stony Brook, and analyzed for thiosulfate and polythionates by IC after 2-5 days. Hydrogen sulfide concentrations were determined on site (HACH method 8131). No attempt was made to determine sulfur present as FeS, elemental sulfur, polysulfide, or other forms of sulfur that may explain the apparent mass balance fluctuations in the profile.
