Solvents ethyl lactate

A cheaper process for the environmentally friendly solvent ethyl lactate uses a membrane to separate ammonia and water by-products. The ammonium lactate made by fermentation of carbohydrates is cracked to lactic acid, which is then esterifled with ethanol. This process eliminates the large amounts of waste salts formed with other processes.248 This solvent has been suggested as a replacement for 80% of the 3.8 million tons of solvent used each year in the United States for electronics, paints, coatings, textiles, cleaning, adhesives, printing, and deicing. 

Aparicio S, Alcalde R (2009) The green solvent ethyl lactate an experimental and theraetical characterization. Green Chem ll(l) 65-78... 

Aqueous Base Dissolution Characteristics. Films of these copolymers were cast on 4" Si wafers and baked at 130°C for 1 minute to remove the casting solvent, ethyl lactate. The film thickness (approximately 1.0 jim) was measured on a Tencor Alphastep. The dissolution rates of these films were then measured by immersion in aqueous tetramethylammonium hydroxide (TMAH) solution (at 23 °C) using a Perkin-Elmer 5900 Development Rate Monitor. The dissolution rates were then measured by immersion in a variety of TMAH solutions of increasing normality (0.14,0.26,0.30,0.60 and 1.0 N). 

Tables 20.4.11 and 20.4.12 present hquid-liquid equilibrium data for the ternary (ethyl lactate + olive oil + a-tocopherol) system at 288.2 and 298.2K. Considering these data, Vicente et al. suggested a liquid-hquid countercurrent process to extract a-tocopherol from olive oil using die green solvent ethyl lactate, the tie-line data of Table 20.4.12 allows the calculation of extraction yield as presented in Figiue 20.4.17 for the temperature of 288.2K. A two-step extraction process is considered. If the (a-tocopherol + olive oil) raw material contains 27 wt% of a-tocopherol (point 1 in Figiue 20.4.17) and is contacted with sufficient ethyl lactate, a biphasic mixture is formed (point 2) comprising an oil-rich phase (point 3) and ethyl lactate-rich phase (point 4, which is connected by the...

Ishida and Chapman " studied ethyl lactate as a green solvent to extract carotenoids from several vegetable sources. The authors determined the carotenoid yield (pg of carotenoid per g of dry weight) at different conditions and the results were compared with extraction carried out with ethanol (another green solvent), ethyl lactate/ethanol mixtures, as well as methylene chloride/methanol/H20 (40/40/20) and ethyl acetate, being the most commonly used solvent for extracting carotenoids for utilization in food products, but not considered to be an environmentally friendly solvent. 

Lyophilized powder (0.2 g) was put in eontaet with 10 mL of 5 mol-L lactic acid at controlled temperature. After eell disruption, the mixture was centrifuged and the liquid phase removed. Then the fraetion of disrupted eells was extracted with 15 mL of organic solvent at room temperature. The proeess parameters were optimized to estimate the best conditions for the extraction yield of astaxanthin and for that, a four-factor three-level orthogonal array design was used. The factors and levels were the following disrupting temperature (35, 50, and 65°C), disrupting time (10, 60, and 110 min), type of solvent (ethyl lactate and ethyl lactate + ethanol in 1/1 and 3/1 ratios) and extraction time (10, 30, and 50 min). 

Alvarez, M.E., Moraes, E.B., Machado, A.B., et al., 2007. Evaluation of liquid-liquid extraction process for separating acrylic add produced from renewable sugars. Applied Biochemistry and Biotechnology 137-140,451-461. Aparido, S., Alcalde, R., 2009. The green solvent ethyl lactate an experimental and theoretical characterization. Green Chemistry 11,65-78. 

The physical properties of finish removers vary considerably due to the diverse uses and requirements of the removers. Finish removers can be grouped by the principal ingredient of the formula, method of appHcation, method of removal, chemical base, viscosity, or hazardous classification. Except for method of apphcation, a paint remover formulation usually has one aspect of each group, by which it can be used for one or more appHcations. A Hst of the most common organic solvents used in finish removers has been compiled (3). Many are mentioned throughout this article others include ethyl lactate [97-64-3] propylene carbonate [108-32-7] furfural alcohol [98-01-1/, dimethyl formamide [68-12-2] tetrahydrofuran [109-99-9] methyl amyl ketone [110-43-0] dipropylene glycol methyl ether [34590-94-8] and Exxate 600, a trade name of Exxon Chemicals. 

Solubility. One of PVP s more outstanding attributes is its solubility in both water and a variety of organic solvents. PVP is soluble in alcohols, acids, ethyl lactate, chlorinated hydrocarbons, amines, glycols, lactams, and nitroparaffins. SolubiUty means a minimum of 10 wt % PVP dissolves at room temperature (moisture content of PVP can influence solubiUty). PVP is insoluble in hydrocarbons, ethers, ethyl acetate, j -butyl-4-acetate, 2-butanone, acetone, cyclohexanone, and chlorobenzene. Both solvent polarity and H-bonding strongly influence solubiUty (77). 

Medium Boiling Esters. Esterificatioa of ethyl and propyl alcohols, ethylene glycol, and glycerol with various acids, eg, chloro- or bromoacetic, or pymvic, by the use of a third component such as bensene, toluene, hexane, cyclohexane, or carbon tetrachloride to remove the water produced is quite common. Bensene has been used as a co-solvent ia the preparatioa of methyl pymvate from pymvic acid (101). The preparatioa of ethyl lactate is described as an example of the general procedure (102). A mixture of 1 mol 80% lactic acid and 2.3 mol 95% ethyl alcohol is added to a volume of benzene equal to half that of the alcohol (ca 43 mL), and the resulting mixture is refluxed for several hours. When distilled, the overhead condensate separates iato layers. The lower layer is extracted to recover the benzene and alcohol, and the water is discarded. The upper layer is returned to the column for reflux. After all the water is removed from the reaction mixture, the excess of alcohol and benzene is removed by distillation, and the ester is fractionated to isolate the pure ester. 

Much work [42] has been devoted to cinchona alkaloid modified Pd and Pt catalysts in the enantioselective hydrogenation of a-keto esters such as ethyl pyruvate (Scheme 5.11). Optimal formulation and conditions include supported Pt, the inexpensive (—)-cinchonidine, acetic acid as solvent, 25 °C and 10-70 bar H2. Presently, the highest e.e. is 97.6% [to (R)-ethyl lactate]. 

Key Words Green solvents, organic Solvents, Vegetable Oil, Ethyl lactate... 

Theoretical calculations proved that the reaction intermediate leading to R-ethyl lactate on cinchonidine-modified Pt(lll) is energetically more stable than the intermediate leading to the S-ethyl lactate [147], However, the catalytic system is complex and the formation and breaking of intermediates are transient, so it is certainly difficult to obtain direct information spectroscopically. It is therefore advisable to use simplified model systems and investigate each possible pairwise interaction among reactants, products, catalyst, chiral modifier, and solvent separately [147, 148]. In order to constitute these model systems, it is important to get initial inputs from specific catalytic phenomena. 

Figure 18. Correlations between the solubility of cmchonidme and the reported empirical polarity (A) and dielectric constants (B) of 48 solvents [66]. Those solvents are indicated by the numbers in the figures 1 cyclohexane 2 n-pentane 3 n-hexane 4 triethylamine 5 carbon tetrachloride 6 carbon disulfide 7 toluene 8 benzene 9 ethyl ether 10 trichloroethylene 11 1,4-dioxane 12 chlorobenzene 13 tetrahydrofuran 14 ethyl acetate 15 chloroform 16 cyclohexanone 17 dichloromethane 18 ethyl formate 19 nitrobenzene 20 acetone 21 N,N-drmethyl formamide 22 dimethyl sulfoxide 23 acetonitrile 24 propylene carbonate 25 dioxane (90 wt%)-water 26 2-butanol 27 2-propanol 28 acetone (90 wt%)-water 29 1-butanol 30 dioxane (70 wt%)-water 31 ethyl lactate 32 acetic acid 33 ethanol 34 acetone (70 wt%)-water 35 dioxane (50 wt%)-water 36 N-methylformamide 37 acetone (50 wt%)-water 38 ethanol (50 wt%)-water 39 methanol 40 ethanol (40 wt%-water) 41 formamide 42 dioxane (30 wt%)-water 43 ethanol (30 wt%)-water 44 acetone (30 wt%)-water 45 methanol (50 wt%)-water 46 ethanol (20 wt%)-water 47 ethanol (10 wt%)-water 48 water. [Reproduced by permission of the American Chemical Society from Ma, Z. Zaera, F. J. Phys. Chem. B 2005, 109, 406-414.]...

The solvents most commonly employed are water, ethyl and methyl alcohol, ether, benzene, petroleum ether, acetone, glacial acetic acid also two or three solvents may be mixed to get the desired effect as described later. If you still cannot dissolve the compound, try some of these chloroform, carbon disulfide, carbon tetrachloride, ethyl acetate, pyridine, hydrochloric acid, sulfuric acid (acids are usually diluted first), nitrobenzene, aniline, phenol, dioxan, ethylene dichloride, di, tri, tetrachloroethylene, tetrachloroethane, dichloroethyl ether, cyclohexane, cyclohexanol, tetralin, decalin, triacetin, ethylene glycol and its esters and ethers, butyl alcohol, diacetone alcohol, ethyl lactate, isopropyl ether, etc. 

In Illinois, engineers have devised a new way of halving the cost of mannfactnring ethyl lactate. The new process uses a fine membrane to efficiently remove water, which is prodnced as a reaction byproduct, and allows the production of lactate esters that are almost pnre. This method of prodnction will make the environmentally benign ethyl lactate a cheap replacement for the harmfnl solvents nsed for paints, glues, inks, and dyes (Knight, 1998). 

Two methods of prepn are listed in Ref 3 a)By esterification of lactic acid with ethanol and b)By combining acetaldehyde with hydrocyanic. acid to form acetaldehyde cyanohydrin, and this is treated wi th ethanol HC1 to ethyl lactate. Used as a solvent for cellulose acetate and nitrate, other cellulose esters, resins, lacquers, paints and enamels Refs l)Beil 3, 264, 267, 280,(102,109) ... 

The results collected in Table 5 suggest that hydrocarbon residues, especially aromatic groups, in the solvent are strongly responsible for the interaction with cis-(1+4). The position of the largest hydrocarbon residue apparently determines whether P- or M-[6]-helicene will be formed in excess. Replacement of the methyl group in (S)-ethyl lactate (b) by a phenyl group giving (S)-ethyl mandelate (d), increases the optical yield fivefold. 

Polymers based on COCs that have been described for photoresists are schematically shown in Figure 2.3. In addition, to the formulation a photoacid generator, di-(4-fcrf-butylphenyl)iodonium-10-camphor sulfonate is added. Other optional additives include anti-striation agents, plasticizers, speed enhancers, etc. Ethyl lactate acts as a solvent (61). Several other types of photoacid generators have been described (62). 

The following solvents are now manufactured on the large scale for industrial purposes ethylene dichloride, di-, tri-, and tetra-chloroethy-lene, tetrachloroethane, dichloroethyl ether, hexahydrobenzene, cyclo-hexanol, tetra- and deca-hydronaphthalene (tetralin and dekalin), triacetin, ethylene glycol, butyl alcohol, diacetone alcohol, ethyl lactate, isopropyl ether, etc. 

Growing concern over volatile organic compound and other emissions is motivating manufacturers to modify processes to capture and recycle solvents, reduce solvent use, or switch to solvents with better environmental profiles. A biobased solvent that is benefiting from this shift is ethyl lactate. 

Ethyl lactate is another lactic acid derivative that has recently been commercialized. An environmentally benign solvent with properties superior to many conventional petroleum-based solvents, it can be blended with methyl soyate derived from soybean oil to create custom-tailored solvents for various applications. 

Until recently, the use of ethyl lactate has been limited owing to high production costs selling prices for ethyl lactate have ranged between 3.30 and 4.40/kg, compared with 2.00 and 3.75/kg for conventional solvents... 

More than 4.5 million metric t of solvents is used in the United States annually, and it has been suggested by industry experts that ethyl lactate could replace conventional solvents in more than 80% of these applications (34). Vertec Biosolvents Inc. is currently using ethyl lactate in soy oil-solvent blends. Applications targeted by Vertec Biosolvents include conventional solvents that are under environmental scrutiny such as methylene chloride, methyl ethyl ketone, and N-methyl pyrrolidone (36). Table 3 lists the selling prices of some common solvents. 

Nikles, S.M., M. Piao, A.M. Lane and D.E. Nikles, Ethyl Lactate A Green Solvent for Magnetic Tape Coating, Green Chemistry, 3, 109-113 (2001). 

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