Total dissolved sulfur concentration

Activity of S is related to total dissolved sulfur concentration (ZS) and pH in the region in which H2S is predominant among aqueous sulfur species. 

If Fe-Mg chlorite is assumed to be in equilibrium with a fluid phase and pyrite, the ratio of Fe + to Mg + in the fluids may be related to factors such as pH, /oj, temperature and total dissolved sulfur concentration (ES). This relationship can be derived from the following chemical reactions ... 

In contrast to the estimation of total dissolved sulfur concentration (ES), the total dissolved selenium concentration (ESe) has not yet been estimated. The Beppu hot springs which are accompanied by Au-Ag siliceous sinter, contain about 10 moI/1 Se (Uzumasa, 1965). For the construction of Figs. 1.93 and 1.94, the Se/S ratio of the ore fluids is assumed to be 10 . ... 

Fig. 1.17 Relation between the and Cl concentrations of geothermal waters and inclusion fluids. The solid line indicates (i) albite-K-feldspar-muscovite-quartz-calcite-solution equilibrium at aHjCOj = 10 (2) albite-K-feldspar-muscovite-quartz-calcite-solution equilibrium at aHjCO, = 10 (3) anhydrite-solution at XSo (total dissolved sulfur concentration) = 10 (4) anhydrite-solution equilibrium at = 10 (Shikazono 1978a, b). For symbols used, see caption to Fig. 1.15...

Fig. 1.28 Stabilities of aqueous sulfur-containing species at XS (total dissolved S concentration) = 0.1 mol/kg H2O, 25 °C. (a) Light, solid contours show as. Changes in the fields of predominance (heavy, solid lines) on decreasing to 0.(K)1 are indicated by the heavy, dashed lines (Barnes and Kullerud 1961)...

Fig. 8. E/2-pH diagrams showing predominance fields of aqueous species and minerals at 25°C. Iron species and minerals are shown in (A) uranium species and minerals are illustrated by (B). The boundaries of the fields were drawn for a total dissolved Fe concentration of 0.01 ppm, a total dissolved carbon concentration of 10 ppm, a total sulfur concentration of 10 ppm, and a total dissolved uranium concentration of 0.001 ppm.

Eberlein and Kattner [194] described an automated method for the determination of orthophosphate and total dissolved phosphorus in the marine environment. Separate aliquots of filtered seawater samples were used for the determination orthophosphate and total dissolved phosphorus in the concentration range 0.01-5 xg/l phosphorus. The digestion mixture for total dissolved phosphorus consisted of sodium hydroxide (1.5 g), potassium peroxidisulfate (5 g) and boric acid (3 g) dissolved in doubly distilled water (100 ml). Seawater samples (50 ml) were mixed with the digestion reagent, heated under pressure at 115-120 °C for 2 h, cooled, and stored before determination in the autoanalyser system. For total phosphorus, extra ascorbic acid was added to the aerosol water of the autoanalyser manifold before the reagents used for the molybdenum blue reaction were added. For measurement of orthophosphate, a phosphate working reagent composed of sulfuric acid, ammonium molyb-... 

The average concentrations of reduced inorganic sulfur species in the anoxic zone of the Black Sea measured using a new colorimetric method developed by Volkov [61,62] are summarized in Table 3. Presented elemental sulfur data refer to the stun of elemental sulfur allotropes (zero-valent sulfur) and the zero-valent sulfur derived from some fraction (n - 1) of the original polysulfide S 2. Thiosulfate data in the table represent the total amount of thiosulfate, sulfite, and polythionates. At some stations in the Black Sea, Volkov [61] observed a concentration maximum of elemental sulfur at the oxic/anoxic interface associated with sulfide oxidation by dissolved oxygen and/or Mn oxyhydroxides. Increasing with depth, elemental sulfur concentrations are probably explained by the ongoing process of polysulfide formation... 

These solutions can contain as much as 60 percent (by volume) hydrochloric or sulfuric acid, depending on the shape of the steel and type of steel (high carbon or low carbon) to be cleaned. The solutions are used until either the acid content is too low (Baume gravity scale), or the iron content is too high (titration technique). By the time it is ready to be discarded, pickling solutions can have very high iron concentrations (60 g/L or 0.5 Ib/gal total dissolve iron). These solutions pose one of the most difficult waste disposal problems for the steel industry. There are a few other industries that can use the solutions (mainly for the acid content), but the volume of the solutions can literally flood the market. 

We make a start by considering a solution with a total sulfur concentration of 1.0 m. Where ions or other dissolved species are present, we also assume that the solutions are ideal that is, activity is equal to the concentration in molarity units. As a first step, consider the reduction of S(s) to the —2 oxidation state represented by S , HS , and H2S. The prevalent dissolved species will depend on the pH and the acid-base equilibrium constants. 

ARD can also produce sulfuric acid at a slower rate, so that the acid neutralizing capacity (ANC) of the aquifer can neutralize the produced acid. In such cases, the total dissolved solids (TDS) concentration of the water can be increased from the dissolution of minerals from the acid-neutralization reaction with the minerals. 

A 8 A solution of chromic acid is prepared by dissolving 26.72 g of chromium trioxide in a mixture of 23 ml of concentrated sulfuric acid and enough water to make the total volume of the solution 100 ml. Rapid dropwise addition of a slight excess of this reagent to an acetone solution (2 % or less) of the hydroxy steroid at room temperature or below with stirring usually results in complete conversion to ketone in less than 10 min. The product is isolated by dilution with water followed by filtration or extraction. 

---