Sodium sulfate electrolytes

A new solid state chemical sensor for sulfur dioxide utilizing a sodium sulfate/rare earth sulfates/silicon dioxide electrolyte has been developed. The addition of rare earth sulfates and silicon dioxide to the sodium sulfate electrolyte was found to enhance the durability and electrical conductivity of the electrolyte. The electrolyte exhibits a Nernstian response in the range of SC gas concentrations from 30 ppm to 1 %. 

The sodium sulfate electrolytes mixed with Y SO and Si02 are better solid electrolytes for the SO- gas detector ... 

Sudoh et al. demonstrated the destruction of phenol via electrolytically generated Fenton s reagent in a ferrous sulfate/sodium sulfate electrolyte. These studies were performed in an H-type electrolyzer (Fig. 12) on a graphite plate cathode [52]. At an operating potential of -0.6 V vs. Ag/AgCl, a solution pH of 3, and a ferrous concentration of 2 mol/m, a phenol degradation current efficiency of 60% was reported for initial phenol values ranging from 260 to 2600 ppm. 

The sodium sulfate electrolyte solution was circulated through the cell and heated to 50°C which also heated the cell to this temperature. Sixty cubic centimeters of the sodium silicate solution was fed into the electrolyte and the electrolyte-sodium silicate mixture circulated to obtain a homogeneous solution. Silica concentration of the homogeneous solution was 0.21 g Si02 per 100 ml. The pH of the solution was 10.35. The total volume of the solution was 10,285 ml. 

Electrolyte concentration 0.06 N sodium sulfate Electrolyte-sol volume 101 Cell outflow pH 9... 

Equation V-64 is that of a parabola, and electrocapillary curves are indeed approximately parabolic in shape. Because E ax tmd 7 max very nearly the same for certain electrolytes, such as sodium sulfate and sodium carbonate, it is generally assumed that specific adsorption effects are absent, and Emax is taken as a constant (-0.480 V) characteristic of the mercury-water interface. For most other electrolytes there is a shift in the maximum voltage, and is then taken to be Emax 0.480. Some values for the quantities are given in Table V-5 [113]. Much information of this type is due to Gouy [125], although additional results are to be found in most of the other references cited in this section. 

Electrolyte. The usual electrolyte used is sodium sulfate. The sulfate ion,, has a low affinity for the wool, but because of its smaller si2e... 

Creighton An electrolytic process for reducing sugars to their corresponding polyols. Glucose is thus reduced to sorbitol, mannose to mannitol, and xylose to xylitol. The electrodes are made of amalgamated lead or zinc the electrolyte is sodium sulfate. Invented in 1926 by H. J. Creighton. 

Table 7.5 Summary of the relationship between ionic strength / and concentration c. As an example, sodium sulfate (a 1 2 electrolyte) has an ionic strength that is three times larger than c...

Electrolytic hydrolysis (E-H) of sodium sulfate offers the pulp and paper industry the capability of reducing or eliminating plant discharge while generating valuable caustic soda and sulfuric acid which can be sold or returned to the process to close the loop [269]. 

ATt is the number of degrees that the freezing point has been lowered (the difference in the freezing point of the pure solvent and the solution). Kt is the freezing-point depression constant (a constant of the individual solvent). The molality (m) is the molality of the solute, and i is the van t Hoff factor, which is the ratio of the number of moles of particles released into solution per mole of solute dissolved. For a nonelectrolyte such as sucrose, the van t Hoff factor would be 1. For an electrolyte such as sodium sulfate, you must take into consideration that if 1 mol of Na2S04 dissolves, 3 mol of particles would result (2 mol Na+, 1 mol SO) ). Therefore, the van t Hoff factor should be 3. However, because sometimes there is a pairing of ions in solution the observed van t Hoff factor is slightly less. The more dilute the solution, the closer the observed van t Hoff factor should be to the expected one. 

We will follow the same procedure as in the naphthalene/benzene example above. You may wish to look over these examples in parallel to see exactly where the difference between an electrolyte and nonelectrolyte manifests itself. We will again begin by calculating the freezing point, ATf. The problem gives us the value of Kf. In solution, the strong electrolyte, sodium sulfate, ionizes as ... 

Other electrolytes, such as sodium sulfate or potassium nitrate, could be chosen for the salt bridge. Neither of these electrolytes interferes in the cell reaction. Silver nitrate, AgN03(aq), would be a poor choice for the salt bridge, however. Positive silver ions would migrate into the half-cell that contains the cathode. Zinc displaces both copper and silver from solution, so both copper(n) ions and silver ions would be reduced at the cathode. The copper produced would be contaminated with silver. 

One possible, although speculative explanation of the effect of the addition of sulfamic acid or sodium sulfate may be based on Eq. (4.9). According to this equation, the variation in the concentration c of a nonreacting electrolyte changes the thickness of the metal-solution interphase, the double-layer thickness It appears that as the thickness of the double layer, decreases, the coercivity of the Co(P) deposited decreases as well. 

Different surfactants are usually characterised by the solubility behaviour of their hydrophilic and hydrophobic molecule fraction in polar solvents, expressed by the HLB-value (hydrophilic-lipophilic-balance) of the surfactant. The HLB-value of a specific surfactant is often listed by the producer or can be easily calculated from listed increments [67]. If the water in a microemulsion contains electrolytes, the solubility of the surfactant in the water changes. It can be increased or decreased, depending on the kind of electrolyte [68,69]. The effect of electrolytes is explained by the HSAB principle (hard-soft-acid-base). For example, salts of hard acids and hard bases reduce the solubility of the surfactant in water. The solubility is increased by salts of soft acids and hard bases or by salts of hard acids and soft bases. Correspondingly, the solubility of the surfactant in water is increased by sodium alkyl sulfonates and decreased by sodium chloride or sodium sulfate. In the meantime, the physical interactions of the surfactant molecules and other components in microemulsions is well understood and the HSAB-principle was verified. The salts in water mainly influence the curvature of the surfactant film in a microemulsion. The curvature of the surfactant film can be expressed, analogous to the HLB-value, by the packing parameter Sp. The packing parameter is the ratio between the hydrophilic and lipophilic surfactant molecule part [70] ... 

Numerous methods for the synthesis of salicyl alcohol exist. These involve the reduction of salicylaldehyde or of salicylic acid and its derivatives. The alcohol can be prepared in almost theoretical yield by the reduction of salicylaldehyde with sodium amalgam, sodium borohydride, or lithium aluminum hydride by catalytic hydrogenation over platinum black or Raney nickel or by hydrogenation over platinum and ferrous chloride in alcohol. The electrolytic reduction of salicylaldehyde in sodium bicarbonate solution at a mercury cathode with carbon dioxide passed into the mixture also yields saligenin. It is formed by the electrolytic reduction at lead electrodes of salicylic acids in aqueous alcoholic solution or sodium salicylate in the presence of boric acid and sodium sulfate. Salicylamide in aqueous alcohol solution acidified with acetic acid is reduced to salicyl alcohol by sodium amalgam in 63% yield. Salicyl alcohol forms along with -hydroxybenzyl alcohol by the action of formaldehyde on phenol in the presence of sodium hydroxide or calcium oxide. High yields of salicyl alcohol from phenol and formaldehyde in the presence of a molar equivalent of ether additives have been reported (60). Phenyl metaborate prepared from phenol and boric acid yields salicyl alcohol after treatment with formaldehyde and hydrolysis (61). 

After the zinc has been removed, the sulfuric acid rich solution is returned to dissolve the next batch of sludge. Over time, the sodium concentrations will read unacceptable levels in the electrolyte. A bleed stream from the zinc cells is constantly being neutralized and filtered. The saturated sodium sulfate solution thus created is crystallized out as sodium sulfate anhydrous for sale to the pulp and paper industry. Table one shows a complete mass balance for a typical batch. 

Fig. 12. The relative viscosity of polyacrylamide-co-acrylates versus different copolymer compositions depending on the presence of the low-molecular-weight electrolyte sodium sulfate. All Samples have the same degree and distribution of polymerization...

Other physical phenomena that may be associated, at least partially, with complex formation are the effect of a salt on the viscosity of aqueous solutions of a sugar and the effect of carbohydrates on the electrical conductivity of aqueous solutions of electrolytes. Measurements have been made of the increase in viscosity of aqueous sucrose solutions caused by the presence of potassium acetate, potassium chloride, potassium oxalate, and the potassium and calcium salt of 5-oxo-2-pyrrolidinecarboxylic acid.81 Potassium acetate has a greater effect than potassium chloride, and calcium ion is more effective than potassium ion. Conductivities of 0.01-0.05 N aqueous solutions of potassium chloride, sodium chloride, potassium sulfate, sodium sulfate, sodium carbonate, potassium bicarbonate, potassium hydroxide, and sodium hydroxide, ammonium hydroxide, and calcium sulfate, in both the presence and absence of sucrose, have been determined by Selix.88 At a sucrose concentration of 15° Brix (15.9 g. of sucrose/100 ml. of solution), an increase of 1° Brix in sucrose causes a 4% decrease in conductivity. Landt and Bodea88 studied dilute aqueous solutions of potassium chloride, sodium chloride, barium chloride, and tetra-... 

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