Upper brine layer

Figure 7. Relative increase in the concentration in the upper brine layer (AC/C) owing to river inflow and eddy diffusional transport of salt from the lower brine layer in the Dead Sea. Concentration increment (AC) computed from Equation 29 for time steps (At) 50 and 100 years. Relative increase shown as a function of increasing concentration in the upper brine layer (C).

Figure 8. Concentration of dissolved solids in the upper brine layer (U.W.M.) as a function of time...

North American Chemical Co. produces borax pentahydrate and decahydrate from Seades Lake brines in both Trona and West End, California (see Chemicals frombrines). The 88 km dry lake consists of two brine layers, the analyses of which are given in Table 11. Two distinct procedures are used for the processing of upper and lower lake brines. Borax is produced in Trona from upper lake brines by an evaporative procedure involving the crystallization of potash and several other salts prior to borax crystallization as the pentahydrate (104). A carbonation process is used in West End, California to derive borate values from lower lake brines (105). Raw lower stmcture brine is carbonated to produce sodium bicarbonate, which is calcined and recrystallized as sodium carbonate monohydrate. The borate-rich filtrate is neutralized with lake brine and refrigerated to crystallize borax. 

Twelve grams of the magenta dye 61 was dissolved in 250ml of methylene chloride and stirred gently with a solution of 12.2g of sodium dithionite in 250 ml of water. A solution of 5 g of benzoyl chloride in 10 ml of dichloromethane was added slowly to the lower organic layer. The pH of the upper aqueous layer was maintained at 5 to 6. The organic layer was separated, washed with dilute aqueous NaOH and brine. The solution was absorbed onto silica gel and rotary evaporated to dryness. The product was washed from the silica with ether. The ether solution was evaporated to yield 8.2 g of the leuco dye 3-(A-benzyl-A-methyl)amino-9-ethyl-l0-ben-zoyl-9,10-dihydrophenazine (62). 

The reaction mixture was transferred into a separating funnel and the two layers were separated. The upper aqueous layer was extracted with dichlor-omethane (3 x 30 mL). The combined organic layers were washed with brine, dried over sodium sulfate and the solvent was evaporated under reduced pressure. 

In order to estimate how long would it take for the Dead Sea water column to become homogeneous, beginning with its present concentration difference between the upper and lower layer, it is necessary to know how the volume of the individual brine layers and rate of salt input vary with time. As these relationships are not known, the following assumptions will be made ... 

U.W.M. and L.W.M. are the upper and lower water masses, or brine layers. Computation for a three-layer model assumes a hypothetical concentration of 100 grams/liter in the upper water mass at time t — 0. Three concentration-time curves computed for different values of the salt input by surface inflow Curve Cj for concentration and discharge as the present mean River Jordan, and curves for twice and four times the present rate of salt input. Equation... 

Figure 9. Fraction of increase in the concentration of the upper water mass (Dead Sea) owing to eddy diffusional transport of salt from the lower brine layer. Computed from Equation 30 for three different values of the surface salt input as identified in Figure 8...

The feomdity of polar and sub-polar waters is, in part, explained by the variable sea ice cover. The freezing process enriches the surface water with brine, which renders the stratification of upper ocean layers unstable. This leads to convection and the up-welling of nutrient-rich water to the surface where, in the presence of sunlight, the food chain of plankton-fish-marine mammals is initiated. 

Even with this unequal distribution there may be little effect on yield of distillate from a substantially fresh water feed hence the high output of the still from distilled water feed. With sea water, 3 to 4% NaCl equivalent, the average or effective boiling point elevation becomes unequal on the two rotors. Thus if a 50% cut is secured and the lower rotor receives twice the feed of the upper, the average residue concentrate of 7% brine from 3.5% feed could be an actual 10% from the upper periphery and 5% from the lower, supposing equal rates of distillation. Actually because of -the different elevations of boiling point (1.1° and 1.8° F.) the rate of evaporation from the upper rotor decreases while that from the lower rotor increases but less than proportionally because of the added thickness of the feed layer. Later experiments at Columbus on the No. 4 machine suggest that this situation existed in the No. 5 still. 

The inside of the cathode is lined with asbestos paper 0.G mm thick. To achieve uniform permeability for brine three layers of paper are used in the lower part of the electrode and only two in the upper part. 

As an example, some of the adsorption levels in Figure IS will be applied to the layered reservoir in Figure 8. The anionic DPES—AOS adsorbs at 0.11 mg/g on sandstone from 2.1% TDS reservoir brine. At this adsorption level, the surfactant can propagate 369 m in the upper, high-permeability layer. The betaine is comparable to the anionic surfactant in terms of gas mobility reduction. However, it adsorbs at 1.3 mg/g on sandstone from the same brine and would only propagate 109 m in the high-permeability layer. In a limestone, on the other hand, the betaine would travel 223 m compared to 20S m for the anionic surfactant. 

One of the best examples of a coacervate is the hydrogen-bonded association complex between the diethyl ether of diethylene glycol and polysilicic acid (8). When salt is added to the mixture in acid solution, two organic layers separate from the brine, the heavier phase containing about 40% silica but the upper phase containing only about 1.5% (see Figure 4.20). 

Typical procedure. (4R,5R)-5-[(R)-(1-BenzYloxy-1-isopropoxYcarbonYl)ntethYl]-4-phenYl-2-oxazolidone, 595, and its enantiomer [421] At 0 °C, pyridine (200 pL, 2.5 mmol) and diphosgene (72 pL, 0.60 mmol) were successively added to a solution of 594 (207 mg, 0.60 mmol) in dichloromethane (2 mL). After stirring at the same temperature for 10 min, the mixture was diluted with water and ethyl acetate. The upper ethyl acetate layer was separated, washed successively with saturated NaHC03 solution and saturated brine, dried over anhydrous MgS04, and then concentrated in vacuo. The residue was purified by column chromatography (hexanes/EtOAc, 4 1—> 3 1) to afford (4R,5R)-5-[(R)-(l-ben2cyloxY-l-isopropoxYcar-bonyl) methyl]-4-phenyl-2-oxazolidone 595 as a colorless oil (199 mg, 90%). 

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