Brine additives

In the United Stales the principal route for making calcium chloride is by the evaporation of underground brines. Additional commercial material is available by the action of hydrochloric acid on limestone. 

Selection of salt or of method of mining selection or treatment of water chlorination of brine addition of process for safe decomposition of NCI3 in chlorine... 

Thionyl chloride (11.5g, 96.4 mmol) was added to 2-nitrophenylacetic acid (8.72g, 48.2mmol) and the suspension was warmed to 50°C and stirred until gas evolution was complete. The resulting solution was concentrated in vacuo and the residue dissolved in CHjClj (30 ml). This solution was added dropwise to a stirred solution of Meldrum s acid (6.94 g, 48.2 mmol) in CH2CI2 (200 ml) under nitrogen at 0 C. The solution was stirred at 0" C for 1 h after the addition was complete and then kept at room temperature for an additional hour. The reaction solution was then worked up by successively washing with dil. HC1, water and brine and dried (MgSOJ. The dried solution was concentrated in vacuo and abs. ethanol (200 ml) was added to the residue. The mixture was... 

Phenyl-3-oxopropanoic acid (25 mmol) and EtjN (87.5 mmol) were dissolved in THF (150 ml) and cooled to —40°C. Ethyl chloroformate (27.5 mmol) was added dropwise to this solution and then the reaction mixture was stirred for 30 min at —20°C. Di-n-hexylamine (27.5 mmol) was added to the suspension and it was stirred at room temperature for an additional hour. The reaction mixture was diluted with water (100 ml) and extracted with ether (400 ml). The extract was washed with aq. 5% HCl (100 ml) and brine (2 X 100 ml) and dried over NajSO. The crude amide was obtained by removal of the solvent in vacuo and phenylhydrazine (25 mmol) was added. The mixture was heated to 100°C for 30 min. The residue was held in vacuo to remove the water formed and then powdered ZnCl2 (125 mmol) was added. The mixture was heated at 170"C with manual stirring for 5 min. The cooled residue was dissolved in acetone (100 ml) and diluted with ether (500 ml). Water (100 ml) was added. The organic layer was separated and washed successively with 5% aq. HCl (100 ml) and brine (2 x 100 ml) and dried over NajSO. The solvent was removed in vacuo, and the residue was recrystallized from EtOAc-hexane. The yield was 79%. 

The previous product was added to LiAlH (6 eq.) in THF. The solution was heated at reflux for 1 h. The excess hydride was destroyed by dropwise addition of water and the resulting mixture filtered through Celite. The filtrate was diluted with EtOAc, washed with brine and dried (Na2S04). The product was an oil (3.4 g, 98%). 

Plant investment and maintenance costs are relatively high for a new iodine plant in the United States or in Japan because of the deep weUs required for brine production and disposal as weU as the corrosive nature of the plant streams. The principal materials cost is for chlorine and for sulfur dioxide, although in the United States the additives used for the brines, such as scale inhibitors and bactericides, also have a considerable influence on costs. 

Solutions of welan are very viscous and pseudoplastic, ie, shear results in a dramatic reduction in viscosity that immediately returns when shearing is stopped, even at low polymer concentrations (230). They maintain viscosity at elevated temperatures better than xanthan gum at 135°C the viscosity half-life of a 0.4% xanthan gum solution is essentially zero, whereas a welan gum solution has a viscosity half-life of 900 minutes (230). The addition of salt to welan solutions slightly reduces viscosity, but not significantly. It has excellent stabiUty and theological properties in seawater, brine, or 3% KCl solutions... 

Emulsifiers are incorporated in oil and synthetic mud formulations to maintain a stable emulsion of the internal brine phase. These materials include calcium and magnesium soaps of fatty acids and polyamines and amides and their mixtures (123,127). The specific chemistry of these additives depends on the nature of the continuous phase of the mud, ie, whether diesel oil, mineral oil, or a synthetic Hquid. Lime is added along with the fatty acid to form the... 

Like brines, alcohols were readily available and widely used as antifreeze Hquids in the early 1900s. Both methanol and ethanol offer exceUent heat transfer and efficient freeze point depression. However, the alcohols have the distinct disadvantage of their low boiling points. During the summer months when the engines operate hot, significant amounts of the alcohols are lost because of evaporation. These evaporative losses result in cosdy make-up requirements. Additionally, the alcohols have very low flash points and potentially flammable vapors. These safety concerns have, particularly in recent years, caused the use of alcohols to be completely discontinued for most heat-transfer systems. 

Typical brines received at an Arkansas bromine plant have 3—5 g/L bromide, 200—250 g/L chloride, 0.15—0.20 g/L ammonia, 0.1—0.3 g/L hydrogen sulfide, 0.01—0.02 g/L iodide, and additionally may contain some dissolved organics, including natural gas and cmde oil. The bromide-containing brine is first treated to remove natural gas, cmde oil, and hydrogen sulfide prior to introduction into the contact tower (48). 

In the United States the primary route for making calcium chloride is by the evaporation of underground brines (see Chemicals frombrines). Additional commercial material is available by the action of hydrochloric acid on limestone. Typically the hydrochloric acid is a by-product of some other commercial process and the conversion to calcium chloride is motivated by waste avoidance (see Hydrogen chloride). 

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