M-Cresylic acid

Trade names o-cresylic acid No data p-cresylic acid m-cresylic acid cresylic acid CAS 1989 HSDB 1989... 

Synonym m-cresylic acid, 1-hydroxy-3-methylbenzene, 3-hydroxytoluene, m-hydroxytoluene, 3-methylphenol, m-methy Iphenol, 3-cresol... 

Synonyms m-cresylic acid 3-hydroxytoluene meta-creso 3-methylphenol. 

Synonyms/Trade Names meta-Cresol, 3-Cresol, m-Cresylic acid, 1-Hydroxy-3-methylbenzene,... 

CAS 108-39-4 EINECS/ELINCS 203-577-9 UN 2076 (DOT) FEMA 3530 Synonyms 3-Cresol m-Cresylic acid 1-Hydroxy-3-methylbenzene 3-Hydroxytoluene m-Hydroxytoluene... 

The cresols occur in cresylic acid, a mixture of the three cresols together with some xylenols and neutral oils, obtained from coal tar distillates. Only the /n-cresol has the three reactive positions necessary to give cross-linked resins and so this is normally the desired material. The o-isomer is easily removed by distillation but separation of the close-boiling m- and p-isomers is difficult and so mixtures of these two isomers are used in practice. 

Chemical Designations - Synonyms Cresylic acid 2,6-Dimetuylphenol 2-Hydroxy-m-xylene 2,6-Xylenol vic-m-Xylenol Chemical Formula 2,6-(CH3)2C4H30H. 

Cremor tsrtaru cream of tartar. Cr pekautschuk, m. n. crepe rubber. Cresylaaure,/. cresylic acid (cresol). 

Synonyms Cresylic acid tricresol methyl-phenol o-cresol m-crtsoV, p-cresol hydroxytoluene... 

Three types of closely related cresols exist ortho-cresol (o-cresol), meta- cresol (m-cresol), and para-cresol (p-cresol). Pure cresols are colorless chemicals, but they may be found in brown mixtures such as creosote and cresylic acids (e.g., wood preservatives). Because these three types of cresols are manufactured separately and as mixtures, they can be found both separately and together. Cresols can be either solid or liquid, depending on how pure they are pure cresols are solid, while mixtures tend to be liquid. Cresols have a medicinal smell (odor) and when dissolved in water, they give it a medicinal smell and taste. Cresols do not evaporate quickly from water, but in rivers and lakes, they can be removed quickly by bacteria. Dissolved cresols can pass through soil into underground water sources. This may be a problem at hazardous waste sites where cresols are buried. Once cresols are in the water table, they may stay there for months without changing. Cresols in air quickly change and break down into smaller chemicals, some of which irritate the eyes. Cresols can also irritate the eyes. 

There are three isomers of cresol o-cresol, p-cresol, and m-cresol. These are described in detail in Chapter 3. In the following discussion, the effects of o-cresol and p-cresol, which have similar toxicities, are generally described prior to those of m-cresol, which is somewhat less toxic. Occasionally, data were available regarding the effects of cresol mixtures (containing the three isomers in varying proportions) and cresylic acids (technical mixtures containing other substances in addition to the three cresol isomers). These are generally discussed after the individual isomers. 

Since before World War II, multimillion pound quantities of cresols have been produced annually in the United States (O Brochta 1949), and domestic production and sales of cresols have steadily increased in recent years. Approximately 57.3 (USITC 1986), 73.3 (USITC 1988), and 82.3 (USITC 1989) million pounds of cresols were produced annually in the United States in 1986, 1987, and 1988, respectively. Respective sales were 56.6 (USITC 1986), 66.8 (USITC 1988), and 72.1 (USITC 1989) million pounds. These production totals include data on the manufacture of cresylic acid and exclude information on cresol production by coke and gas-retort ovens. The commercial mixture of cresol isomers, in which the m-isomer predominates and contains less than 5% phenol, is sometimes referred to as cresylic acid (Windholz et al. 1983). However, cresylic acids generally are composed of cresols, phenols, and xylenols they are defined as those mixtures in which over 50% will boil at temperatures above 204 C (Sax and Lewis 1987). In 1987, the national capacity for producing cresylics was 208 million pounds per year (CMR 1987). Information regarding the production levels of individual isomers and specific mixtures was unavailable. 

Cresol, Cresylic Acid or Methylphenol (called Kresol or Oxytoluol in Ger), CH3.CgH4.OH mw 108.13, 0 14.79% A coml coal tar product of the middle heavy oil fractions. It contains a mixt of o-, m- p- isomers which may be separated by fractional distillation into two fractions o- and a mixt of m- p-cresols. The props of cresol depend upon the compn proportion of isomers in the mixt. See Kirk Othmer (Ref 5) for more details o Cresol, wh crysts, phenol-like odor, poisonous, mp 30.8°, bp 191°, d 1.048 at 20° sol in ale, eth chlf si sol in w (Refs 1 7). Prepn other props are given in Beil (Ref 1)... 

Figure 9 MECC of cresylic acid and process impurities at pH 7. Conditions capillary, 72 cm X 50 p,m i.d. bubble factor 3 BGE, 20 mM phosphate, 50 mM SDS, pH 7 injection, 50 mbs detection, UV, 191 nm temperature, 50°C voltage, 30 kV (18-s ramp) sample, 1.5% cresylic acid dissolved in water.

SYNS CARBAMIC ACID, METHYL-, 3-METHYLPHEN-YL ESTER (9CI) CARBAMIC ACID, METHYE, 3-TOLYL ESTER m-CRESYL METHYLCARBAMATE DICRES-YL DICRESYL N-METHYLCARBAMATE DRC 3341... 

The structures of the lignins are amenable to conversion to several classes of substituted phenols by thermochemical and thermal degradation methods. The displacement of pyroligneous tars by coal tars eliminated much of the demand that existed for the lignin-based products. Creosote oil or cresylic acid, a mixture of o-, m-, and p-cresols, is now manufactured mainly from coal tars, while only small amounts of cresols are made from wood tars. The use of wood tars and other biomass-derived tars as substitutes for a major portion of the phenol and formaldehyde in phenol-formaldehyde resins could reverse this trend (Himmelblau, 1995). The key to this process seems to be that the... 

To make 500 mL of 0.5% cresyl violet of about pH 3.9, mix 2.5 g of cresylecht violet (Chroma Gesellschaft, Postfach 11 10, D-73257, Kongen, Germany, Fax number 49-7024-82660), 300 mL of water, 30 mL of 1.0 M sodium acetate (13.6 g of granular sodium acetate in 92 mL of water), and 170 mL of 1.0 M acetic acid (29 mL of glacial acetic acid added to 471 mL of water). Mix this solution for at least 7 days on a magnetic stirrer, then filter. 

Xylenol Cresylic Acid 2,6-Dimethylphenol 2-Hydroxy- M-Xylene 2.6-Xylenol Vic-M-Xylenol... 

Since the solvents employed must be insoluble or nearly so in the hydrocarbon feed, process development necessarily focused on solvents with polar structures. The solvents that eventually achieved significant commercial use (Figure 6.1 and Table 6.1) are liquid sulfur dioxide (I), nitrobenzene (II), phenol (III), cresylic acid (o-, m-, p-cresol) (IV), p,P-dichloroethylether (Chlorex,V), furfural (VI), and n-methyl-2-pyrollidone (NMP, VII). The Duo-Sol process2 employs a... 

Thymyl jY-Isoamylcarbamate. /soamvfcarftamic acid rhymyf ester isopropyl -m-cresyl ester of isoamylcar-bamic acid Egressin. mol wt 263.37. C... 

Caswell No. 757A Cresol sodium salt, Cresylic acid sodium salt EINECS 252-154-5 ERA Pesticide Chemical Code 357200 HSDB 5139 Methylphenol sodium salt Phenol, methyl-, sodium salt Sodium cresolale Sodium cresoxide Sodium cresylate. Mixture of 0, m and p-isomers,... 

Murray, M.J., 1949. Total phenols in gasolines and in cresylic acids — spectrophotometric determination. Anal. Chem., 21 941—945. 

These reactions have b n carried out both under traditional conditions, i.e. high-temperature polycondensation in m-cresol and application of benzoic acid as catalyst [99] and in a ries of other solvents [190] - mixtures of m-cresol and polyphosphoric acid, m-cresol and di-m-cresyl phosphate, m-cresol... 

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