(2) Low-boiling, straw color.
(3) Special resin grade, high-boiling.
There are four domestic producers of cresylic acid with recovery and refining units at Pittsburgh, Pa., Philadelphia, Pa., Indianapolis, Ind., and Follansbee, W. Va. The last three mentioned are refining plants operated in conjunction with a number of tar distillation units widely scattered throughout the country. These units usually recover crude tar-acid fractions in the distillation of tar and ship them to these refining plants for separation and refining. All in this group are purchasers of coal tar. The fourth producer operates a byproduct recovery unit in connection with the company’s coke-oven operations. Part of the coal tar produced is distilled to recover the several products, including creosote oil, tar acids, and naphthalene, and the residual pitch is mixed with the remaining undistilled tar and used for fuel. The shortage of tar acids and naphthalene in 1936 caused this producer to begin the topping of tar.
Foreign production.
The cresols are produced in the United Kingdom, Germany, France, the Netherlands, Belgium, and other European countries. Coal tar recovered in the United Kingdom is principally gas tar, which is much richer in tar acids than coke-oven tar, the principal source in the United States. This is true because low temperature carbonization of coal yields greater quantities of tar acids than are obtained in the tar from byproduct coke ovens. Exports to the United States are chiefly mixtures which can enter as crude cresylic acid.
Production of cresol in Germany in recent years is shown in table [69].
Table 69.—Cresol: German production, in specified years
| Year | 1,000 pounds |
|---|---|
| 1929 | 23,814 |
| 19311 | 15,435 |
| 1933 | 11,780 |
| 1934 | 10,476 |
1 Includes 2,866,000 pounds of separated ortho, meta, and para cresols.