Ethylene oxide, hydration

The surfactant in this case, L64, is a member of the Pluronic family (marketed by BASF) these are triblocks composed of poly(ethyleneoxide) (PEO) and poly(propyleneoxide) (PPO) blocks. Some of these surfactants are popular in drug delivery, others are used in washing powders and personal care products such as toothpaste. The surfactants are soft they are mild to the skin. The amphiphilic power is modest too. The hydrophilic block PEO is only slightly less hydrophobic than the PPO block. In fact, the solubility of PEO is an unresolved mystery in itself, maybe related to the cage structure of the hydrated ethylene oxide monomer. Poly (methylene oxide) is insoluble, PEO is soluble, PPO and poly (butylene oxide) and higher are all insoluble. 

HOCHj CHjOH. Colourless, odourless, rather viscous hygroscopic liquid having a sweet taste, b.p. 197 C. Manufactured from ethylene chlorohydrin and NaHC03 solution, or by the hydration of ethylene oxide with dilute sulphuric acid or water under pressure at 195°C. Used in anti-freezes and coolants for engines (50 %) and in manufacture of polyester fibres (e.g. Terylene) and in the manufacture of various esters used as plasticizers. U.S. production 1979 1 900 000 tonnes. 

Tin(ll) chloride Boron trifluoride, ethylene oxide, hydrazine hydrate, nitrates, Na, K, hydrogen peroxide... 

Although catalytic hydration of ethylene oxide to maximize ethylene glycol production has been studied by a number of companies with numerous materials patented as catalysts, there has been no reported industrial manufacture of ethylene glycol via catalytic ethylene oxide hydrolysis. Studied catalysts include sulfonic acids, carboxyUc acids and salts, cation-exchange resins, acidic zeoHtes, haUdes, anion-exchange resins, metals, metal oxides, and metal salts (21—26). Carbon dioxide as a cocatalyst with many of the same materials has also received extensive study. 

Denture Adhesives. Fast hydration and gel-forming properties are ideally mated to produce a thick, cushioning fluid between the dentures and gums (100). The biologically inert nature of poly(ethylene oxide) helps reduce unpleasant odors and taste in this type of personal-care product (see... 

Glathrate Formation. Ethylene oxide forms a stable clathrate with water (20). It is non stoichiometric, with 6.38 to 6.80 molecules of ethylene oxide to 46 molecules of water iu the unit cell (37). The maximum observed melting poiat is 11.1°C. An x-ray stmcture of the clathrate revealed that it is a type I gas hydrate, with six equivalent tetrakaidecahedral (14-sided) cavities fully occupied by ethylene oxide, and two dodecahedral cavities 20—34% occupied (38). 

With Water. Wurtz was the first to obtain ethylene glycol by heating ethylene oxide and water in a sealed tube (1). Later, it was noted that by-products, namely diethjlene and triethylene glycol, were also formed in this reaction (50). This was the first synthesis of polymeric compounds of well-defined stmcture. Hydration is slow at ambient temperatures and neutral conditions, but is much faster with either acid or base catalysis (Table 8). The type of anion in the catalyzing acid is relatively unimportant (58) (see Glycols). 

With Acyl Halides, Hydrogen Halides, and Metallic Halides. Ethylene oxide reacts with acetyl chloride at slightly elevated temperatures in the presence of hydrogen chloride to give the acetate of ethylene chlorohydrin (70). Hydrogen haUdes react to form the corresponding halohydrins (71). Aqueous solutions of ethylene oxide and a metallic haUde can result in the precipitation of the metal hydroxide (72,73). The haUdes of aluminum, chromium, iron, thorium, and zinc in dilute solution react with ethylene oxide to form sols or gels of the metal oxide hydrates and ethylene halohydrin (74). 

Davis et al. [9] have performed studies on the bateh hydration of ethylene oxide. Their work determined the value of the produet distribution eonstant K. This value is used in Equation 5-378 to determine the expeeted performanee in a plug flow reaetor. This value is also used in Equation 5-394 to illustrate the poor performanee that would be obtained with eomplete baekmixing. 

The main route for producing ethylene glycol is the hydration of ethylene oxide in presence of dilute sulfuric acid (Eigure 7-4) ... 

Propylene glycol (1,2-propanediol) is produced by the hydration of propylene oxide in a manner similar to that used for ethylene oxide ... 

Flocculants cause colloidal clay particles to coagulate thus promoting separation from the drilling fluid which has been circulated down the wellbore and returned to the surface. The treated fluid may then be pumped back down the well bore. Sodium chloride, hydrated lime, gypsum, sodium tetraphosphate, polyacrylamide, poly(acrylamide-co-acrylic acid), cationic polyacrylamides, and poly(ethylene oxide) have been used commercially. 

The half-life (t 1/2) of a reactant is the time required for its concentration to decrease to one-half its initial value. The rate of hydration of ethylene oxide (A) to ethylene glycol (C2H4O + H2O - C2H6O2) in dilute aqueous solution is proportional to the concentration of A with a proportionality constant kA = 4.11 X 10-5 s-1 at 20°C for a certain catalyst (HCIO4) concentration (constant). Determine the half-life (ti/2), or equivalent space-time (T1/2), in s, of the oxide (A) at 20°C, if the reaction is carried out... 

The rate of hydration of ethylene oxide (A) to ethylene glycol (C2H40 4- H20 C2H602)... 

Suppose the liquid-phase hydration of ethylene oxide (A) to ethylene glycol, CzHtOiA) + H2O - C2H6O2, takes place in a CSTR of volume (V) 10,000 L the rate constant is fcA = 2.464 X10-3 min-1 (Bronsted et al., 1929 see Example 4-3). 

Our Form II has two uncommon features. In the first place it contains two hydroxyl groups attached to the same carbon but we have that in chloral hydrate. In the second place there is an ethylene oxide oxygen linkage. This might be called an alpha lactone with the water not split off. This formation of a ring structure is believed to account for the reversal of the sign of rotation. It is well known that the formation of the lactide from lactic acid, while not a lactone formation in the same... 

Fries rearrangement, 18 336, 337 isomerization and transalkylation of alky-laromatics, 18 329 epoxide transformations, 18 351-352 hydration and ammonolysis of ethylene oxide, 18 351, 352 isomerization, 18 351 framework composition, 33 226-228 hydrogenation, dehydrogenation, and related reactions, 18 360-365 dehydrocyclization of s-ethylphenyl using zeolites and carbonyl sulfide, 18 364, 365... 

Propylene glycol is produced by hydration of propylene oxide in a process similar to that for the production of ethylene glycol by hydration of ethylene oxide. 

McMullan, R.K. Jeffrey, G.A. (1965). Polyhedral Clathrate Hydrates. IX. Structure of Ethylene Oxide Hydrate. J. Chem. Phys., 43 (8), 2725-2732. 

You wish to design a plant to produce 100 tons/day of ethylene glycol from ethane, air, and water. The plant has three reactor stages, ethane dehydrogenation, ethylene oxidation, and ethylene oxide hydration. 

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