Industrial solvents ethyl acetate

The industrial solvent ethyl acetate is produced by reaction of acetic acid with ethanol ... 

Esters are widely used in industry as solvents. Ethyl acetate is a good solvent for a wide variety of compounds, and its toxicity is low compared with other solvents. Ethyl acetate is also found in household products such as cleaners, polishes, glues, and spray finishes. Ethyl butyrate and butyl butyrate were once widely used as solvents for paints and finishes, including the butyrate dope that was sprayed on the fabric covering of aircraft wings to make them tight and stiff. Polyesters (covered later in this section and in Chapter 26) are among the most common polymers, used in fabrics (Dacron ), films (VCR tapes), and solid plastics (soft-drink bottles). 

Data was obtained for three organic solvents, ethyl acetate, toluene and methanol - these solvents are commonly used in the pharmaceutical and chemical industries. STARMEM 122, an asymmetric OSN membrane with an active layer of polyimide, in a dry form but with a lube oil soaked into the membrane as a preserving agent, with a nominal MWCO of 220 g-moh (manufacturers data) was supplied by Membrane Extraction Technology Ltd (UK). 

Ethanol (industrial solvent used in preparation of ethyl acetate unleaded gasoline additive)... 

The chemical industry uses esters for a variety of purposes. Ethyl acetate, for instance, is a commonly used solvent, and dialkyl phthalates are used as plasticizers to keep polymers from becoming brittle. You may be aware that there is current concern about possible toxicity of phthalates at high concentrations, although a recent assessment by the U.S. Food and Drug Administration found the risk to be minimal for most people, with the possible exception of male infants. 

Plant carotenoids are still extracted at laboratory and industrial scales with solvent mixtnres of ethanol and ethyl acetate, bnt solvent extraction always bears the risk of toxic residnes in the extracts and this limits their use in large production applications in the food and pharmaceutical industries. 

The above solution procedure has been applied to find replacement solvents for the following solvents Ethyl Glycol Acetate, Ethyl Glycol and Methylene Chloride. These three solvents are extensively used in the paints and ink industry, although, recent studies have shown that they carry an appreciable environmental burden in addition to being found harmful for the health of the people exposed to them (for example, employees in the manufacturing plants and/or consumers). 

According to Coimbra et solvents play a central role in the majority of chemical and pharmaceutical industrial processes. The most used method to obtain artemisinin (1) from A. annua is through the use of organic solvents such as toluene, hexane, cyclohexane, ethanol, chloroform and petroleum ether. Rodrigues et al described a low-cost and industrial scaled procedure that enables artemisinin (1) enhanced yields by using inexpensive and easy steps. Serial extraction techniques allowed a reduction of 65% in solvent consumption. Moreover, the use of ethanol for compound extraction is safer when compared to other solvents. Flash column pre-purification employing silicon dioxide (Zeosil ) as stationary phase provided an enriched artemisinin (1) fraction that precipitated in hexane/ethyl acetate (85/15, v/v) solution. These results indicate the feasibility of producing artemisinin (1) at final cost lowered by almost threefold when compared to classical procedures. 

Table 9.2 summarizes the uses of acetic acid. Vinyl acetate is another top 50 chemical. Acetic anhydride is used to make cellulose acetate and at times has been in the top 50 chemicals itself. Cellulose acetate is a polymer used mainly as a fiber in clothing and cigarette filters. Ethyl acetate is a common organic solvent. Acetic acid is used as a solvent in the manufacture of terephthalic acid (TA) and dimethyl terephthalate (DMT), which are monomers for the synthesis of poly(ethylene terephthalate), the polyester of the textile industry. A minor household use of acetic acid is as a 3-5% aqueous solution, which is called vinegar. 

Of course, a number of solvents in common use in the chemical industry, such as ethanol, acetic acid, and ethyl acetate, can be derived from either bio or oil raw materials. The debate rages over the hfe cycle impact of bio versus fossil fuel... 

Ethyl acetate is used in production of acrylic plastics. Ethyl acetate and butyl acetate find wide usage as solvents for nitrocellulose and lacquers. Hthyl acetate is considered one of the least toxic of all industrial organic solvents. Buiyl acetate s chief industrial competitor is methyl isobutyJ ketone. Over lime, ethyl acetate and butyl acetate may suffer the same fate as methyl acetate, which hos been largely displaced by other solvents. 

Photo-oxidation of citronellol in polystyrene beads [120]. A sample of 3.0 g of polystyrene beads (commercial, cross-polymerized with 1% of divinylbenzene) was treated with a solution of 2 mg of tetraphenylporphyrin and 780 mg (5 mmol) of citronellol in 20 mL of ethyl acetate in a petri-dish (30 cm diameter). After 2h in a ventilated hood, the solvent has evaporated and the petri-dish was covered with a glass plate and irradiated for 5 h with a 150 W halogen lamp. The solid support was then washed with 3 x 20 mL of ethanol, the combined ethanol fractions were rota-evaporated and 900 mg of the hydroperoxide mixture (96%) was isolated as a slightly yellow oil. The hydroperoxides were quantitatively reduced to the corresponding allylic alcohols by treatment with sodium sulfite. One of these products is used in the industrial synthesis of rose oxide. 

Some esters have characteristic fruity smells and are generally used as excellent industrial solvents. Esters like ethyl ethanoate, also called ethyl acetate, are used as a solvents for glues. It is this compound that glue sniffers love. Unfortunately they do not realize that it kills off brain cells and can eventually lead to death. 

The transformation of the laboratory protocol into this successful industrial process was facilitated by i) the addition of an organic base (diisopropylethyla-mine), which substantially increased both the ee and the productivity ii) the addition of the appropriate amount of water (0.5/1 with respect to Ti) which directly influenced the stereochemical outcome Hi) the use of a 1 2 ratio of [Ti(0- -Pr)4] and diethyl tartrate iv) the use of cumene hydroperoxide as the oxidant v) the replacement of chlorinated solvents with more environmentally friendly ones (toluene, ethyl acetate) and vi) carrying out the oxidation at higher and technically more convenient temperatures than before ( 0-30°C vx. -20°C). 

Thirty-nine different dithiocarbamates have been efficiently prepared through a one-pot reaction of an aliphatic primary or secondary amine, carbon disulfide and an alkyl halide (Figure 2.16). " Typically, all reagents were liquids and the mixture slowly solidified upon reaction. Therefore, although the reaction does not use solvents, the reagents are probably acting as the solvent in this procedure. Additionally, the reactions were quenched with water and extracted with ethyl acetate, so solvent was used. Nevertheless, this is an excellent synthetic method for the preparation of S-alkyl dithiocarbamates, which are useful compounds for the pharmaceutical and agrochemical industries. 

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