Glycol solutions

Fig. 2. Freezing points of aqueous glycol solutions. A, ethylene glycol B, diethylene glycol C, triethylene glycol and D, tetraethylene glycol. Ethylene glycols...

Water—Glycol Solutions. These materials are transparent solutions of water and glycol having good low temperature properties. They frequently contain water-soluble additives to improve performance in corrosion resistance, anti-wear, etc. A water-soluble polymer is commonly utilized to boost viscosity. As solutions their advantage over emulsions is their inherent stabdity. 

Fig. 1. Solubility of vanillin in (a) ethanol solutions, (b) propylene glycol solutions, and (c) glycerol solutions, where A is 40°C B, 30°C C, 20°C D, 10°C ...

Vapor Pressure of Aqueous Diethylene Glycol Solutions... 

FIG. 2-3 Vapor pressure of aqueous diethylene glycol solutions. Coutiesy of Cafhide and Carhon Chemicals Coip.)... 

Certain chemicals (sorbents) have the ability to absorb moisture from a gas they may be either solid or liquid. Performance of a chemical dehumidifi cation device depends on the sorbent used. The sorbent must t>e able to attract and remove the sorbate, such as water, from the gas stream, Stirbems absorb water on the surface of the material by adsorption or by chemically combining with water (absorption). If the unit is regenerative, the process is reversible, allowing water to be removed. This is achieved by a sorbent such as silica gel, alumina gel, activated alumina, lithium chloride salt, lithium chloride solution, glycol solution, or molecular sieves. In the case of nonregenerative equipment, hygroscopic salts such as calcium chloride, urea, or sodium chloride are used. 

Liquid Sorption. If a moist gas is passed through sprays of a liquid sorbent, such as lithium chloride or an ethylene glycol solution, moisture is removed from the air at a rate depending on the vapor pressure difference. This is a function of the absorbent concentration and is maintained at the required level by a regeneration cycle. The regeneration process is continuous and is achieved by allowing a percentage of the chemical into the exhaust-heated air. 

Substance zones are produced that mainly yield blue fluorescence under long-wavelength UV light (A = 365nm) (indoles occasionally fluoresce yellow [15]), colored zones are also produced occasionally. The fluorescence is stabilized by immersing in 20% methanohc polyethylene glycol solution [5]. 

The action of potassium hydroxide on a solution of 2-( -phenyI-cthyl)-3-isopropyloxazirane (20) in glycol solution gives a mixture of acetophenone (0.25 mole), isobutyraldehyde (0.57 mole), and ammonia (0.92 mole). ... 

Calcium chloride solutions Sodium chloride solutions COj liquid Chlorine liquid Methanol solutions Ethanol solutions Ethylene glycol solutions... 

HF-C Water-glycol solutions. These usually contain at... 

Soldered brass seldom gives trouble. In radiators, antifreeze solutions have been alleged to cause corrosion, possibly because materials such as ethylene glycol sometimes detach protective deposits. Sodium nitrite, valuable as a corrosion inhibitor for other metals in a radiator, tends to attack solders, but sodium benzoate is safe and, in addition, protects the soldered joint against the action of nitrites. In an investigation of other inhibitors in ethylene glycol solutions, 1% borax, either alone or in combination with 0-1% mercaptobenzothiazole, appeared to be satisfactory. 

Where pH levels have dropped below 7.0 due to glycol degradation, there is usually little alternative but to drain, flush, repassivate, and refill with a new inhibited glycol solution. 

In a continuous process, ground PET bottles (830 parts) in an aqueous slurry were pumped into an autoclave equipped with a stirrer and maintained at 450-550 psig pressure and 191-232°C. Ammonium hydroxide (300 parts) solution consisting of water (7857 parts), ethylene glycol (493 parts), and ammonium sulfate (918 parts) was introduced into the reactor. The retention time in the reactor varied from 5 to 45 min. The aqueous diammonium terephthalate and edtylene glycol solution was withdrawn from the reactor and filtered while hot to remove solid impurities such as pigments, pieces of metal caps, labels, and cap liners. Hie filtrate was acidified widi sulfuric acid solution to liberate the TPA product. Hie recovered TPA usually had a purity of 99% or higher. 

At various temperature levels 0-50°F, chilled brine and glycol solutions -50-40°F, ammonia, freons, butane -150-50°F, ethane or propane. 

Amorphous films of the (Zn,Fe)S semiconductor have been obtained by electrodeposition on TO substrates from a diethylene glycol solution containing Ss, FeCl2, and ZnCl2 reagents [102]. The films were annealed at 285 °C in argon to give sphalerite and pyrrhotite (Zn,Fe)S phases. A direct relationship was observed... 

Thin films of ternary cadmium sulfoselenide CdS Sei-x have been electrodeposited from a non-aqueous organic bath by Baranski et al. [67], as well as by Loutfy and Ng [121], who employed similar principles (deposition from ethylene glycol solution... 

Baranski AS, Fawcett WR (1984) The mechanism of electrodeposition of cadmium sulfide on inert electrodes from diethylene glycol solutions. J Electrochem Soc 131 2509-2514... 

Sanders BW, Cocivera M (1987) Characterization of cadmium selenide electrodeposited from diethylene glycol solution containing tri-n-butylphosphine selenide. J Electrochem Soc 134 1075-1080... 

The inorganic nitrite used as a corrosion inhibitor in aqueous alkylene glycol or polyoxyalkylene glycol solutions can be replaced with polyoxyalkylene amines [1263,1264]. Such polyoxyalkylene amines impart corrosion inhibition to the liquid in contact with the metal and the metal in contact with the vapors of the aqueous composition. Aqueous compositions containing the glycol and the polyoxyalkylene amine also exhibit a low foaming tendency. 

Acute Toxicity. The LD50 following oral administration of parathion, either in propylene glycol solutions or in aqueous suspensions of the 15% wettable powder, has been determined for rats, mice, and guinea pigs. The lethal dose was approximated for rabbits and dogs. The results of these experiments are summarized in Table I. Statistical evaluation was by the method of Wilcoxon and Litchfield (11). 

As the concentration of parathion in the propylene glycol solutions is increased, it follows that the area covered by the solution is decreased. That this is a factor in toxicity is indicated by the greater toxicity of the 10 mg. per ml. solution than the 50 mg. per ml. solution. This relationship appears to be true also of the various dry preparations, in that the 1% powder is somewhat more toxic than the 15%. The addition of water to convert the powder to paste does not appreciably influence the toxicity. In comparable concentrations the wettable powder formulation is less toxic than the propylene glycol solution. 

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