Glycol ethers manufacture

Propylene oxide [75-56-9] (methyloxirane, 1,2-epoxypropane) is a significant organic chemical used primarily as a reaction intermediate for production of polyether polyols, propylene glycol, alkanolamines (qv), glycol ethers, and many other useful products (see Glycols). Propylene oxide was first prepared in 1861 by Oser and first polymerized by Levene and Walti in 1927 (1). Propylene oxide is manufactured by two basic processes the traditional chlorohydrin process (see Chlorohydrins) and the hydroperoxide process, where either / fZ-butanol (see Butyl alcohols) or styrene (qv) is a co-product. Research continues in an effort to develop a direct oxidation process to be used commercially. 

Process Raw Material. Industrial solvents are raw materials in some production processes. Eor example, only a small proportion of acetone is used as a solvent, most is used in producing methyl methacrylate and bisphenol A. Alcohols are used in the manufacture of esters and glycol ethers. Diethylenetriamine is also used in the manufacture of curing agents for epoxy resins. Traditionally, chlorinated hydrocarbon solvents have been the starting materials for duorinated hydrocarbon production. 

The manufacturing process for organo-soluble EHEC is similar to that for EC except that alkah cellulose reacts first with ethylene oxide to a low hydroxyethyl MS value of - 0.5 at a low temperature, - 50° C, followed by reaction of the ethyl chloride at a higher temperature. Additional by-products, which are removed during purification, include glycols and the reaction products of the glycols with ethyl chloride (glycol ethers). 

Propylene oxide (PO) is an important intermediate in the manufacture of a wide range of valuable products propylene glycol, ethers, isopropanolamines, and various propoxylated products for polyurethanes (1). The current processes for the large scale synthesis of PO include (i) the chlorohydrin process and (ii) the peroxide process (1, 2). 

Uses. Nearly half the ethyl alcohol produced in petrochemical plants (not the stuff fermented for human consumption) is used as a chemical intermediate in the manufacture of ethyl acrylate, ethyl amines, ethyl acetate (when you pop the cap on nail polish remover, you smell ethyl acetate), ethylene chloride, glycol ethers, acetaldehyde, and acetic acid. However, you will see in the chapters on acetaldehyde and acetic acid, there are now more competitive routes than those based on ethyl alcohol. 

VOCs found in water-based paints in the Netherlands and Denmark (by a survey of manufacturers) are presented in Table 16.3. VOC emission assessments have shown that most of these VOCs are emitted from water-based paints, though with significant variation from product to product in type and quantity of VOC emitted. For example, Table 16.4 presents the VOC emissions from wet products under identical test conditions (Brown, 2000). WBP1 has no 1,2-propylene glycol while the other paints all use large quantities, apparently replacing the glycol ethers and esters. 

MW 44.06 unstable, ring cleaves readily CAS [75-21-8] used as a fumigant and sterilizing agent, and in the manufacture of many glycol ethers and ethano-lamines colorless gas with ether-like odor liquefies at 10.4°C density 0.88 g/mL at 10°C vapor pressure 1095 torr at 20°C soluble in water and most organic solvents highly flammable, toxic, and severe irritant. 

Ethylene glycol is traditionally associated with use as permanent-type antifreeze for internal-combustion engine cooling systems. Other uses include the production of polyesters for fibers, films, and coatings, in hydraulic fluids, in the manufacture of low freezing-point explosives, glycol ethers, and deicing solutions. 

Ethylene oxide is used for manufacture of ethylene glycol, the latter being an antifreeze compound as well as a raw material for production of polyethylene terephthalate used in the manufacture of polyester fibers for preparation of surfactants for the manufacture of ethanolamines for production of ethylene glycols used in plasticizers, solvents, and lubricants and for making glycol ethers used as jet-fuel additives and solvents. 

The butyl glycol ethers are also primarily coatings end use oriented. Approximately 22 percent of U.S. n-butanol demand is consumed in the manufacture of ethylene glycol mono-n-butyl ether (butyl CELLOSOLVER) and diethylene glycol mono-n-butyl ether (butyl CARBITOLR). 

Glycol ethers are extensively used in industrial applications as solvents for the manufacture of lacquers, varnishes, resins, printing inks, and textile dyes as antiicing additives in brake fluids and as gasoline additives. In addition, they are used in consumer products such as latex paints and cleaners. 

Propylene oxide is widely used in the chemical industry as an intermediate in the production of a broad spectrum of materials, such as polyether polyols, propylene glycol, and propylene glycol ethers. These products are further used in the manufacture of polyurethane, lubricants, and detergents. Propylene oxide is used for the fumigation of dried fruit and various other foodstuffs. Propylene oxide is also used for embedding tissues for electron microscopy. 

Approximately 65% of the PO produced is used for the synthesis of polyether polyols (in a reaction with polyhydric alcohols), one of the main components used in the manufacture of polyurethanes, propene glycol (20%), glycol ethers (5%) and butanediol, amongst others. Figure 6.1 shows an overview of the PO industry. 

Propylene oxide (PO) is an important chemical intermediate, which is mainly used in the manufacture of polyols, propylene glycols, and propylene glycol ethers [1]. The world annual production capacity of PO is about 7 million metric tons [2]. PO is mainly produced commercially by either the chlorohydrin (about 43%) or organic hydroperoxide processes. The chlorohydrin route produces large amounts of salt by-product, and new plants have used the hydroperoxide processes [3]. 

Butoxyethanol and 2-butoxyethanol acetate do not occur naturally. Little quantitative information was found in the available literature characterizing the release of these chemicals to the environment. 2-Butoxyethanol and 2-butoxyethanol acetate may be released to air, water, or soil from facilities where they are manufactured or processed. However, information about the release of 2-butoxyethanol is not available in the TRI database because the database contains such information only for the general toxic chemical category of glycol ethers and not for specific glycol ethers (EPA 1995). No information is available in the TRI database on the amount of 2-butoxyethanol acetate released to air, water, or soil by facilities that manufacture or process this compound because this compound is not included under SARA, Title III, and therefore, is not among the chemicals that facilities are required to report (EPA 1995). 

CMA. 1997a. Ethylene glycol ethers panel toxicology summary report. Chemical Manufacturers Association, Arlington, VA. 

Shepard KP. 1994b. Ethylene glycol monobutyl ether acute oral toxicity study in the guinea pig. Eastman Kodak Company, Rochester, NY. Sponsored by Ethylene Glycol Ether Panel, Chemical Manufacturers Association, Washington, D C., EGE-58.0-GPIG-EASTMAN. HAEL no. 94-0300, KAN 902270. 

---