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Cresols (o-, m- and p-), xylenols and cresylic acids are phenolic compounds or mixtures used as raw materials for a variety of synthetic applications, polymer intermediates and also as solvents. Cresols and xylenols are obtained from a variety of sources. Generally, the two main avenues for obtaining cresols and/or xylenols are from natural sources (coal tars, coal gasification extracts) or synthetic processes. Synthetic cresols and xylenols are produced by a variety of processes. Production of synthetic cresols and xylenols from toluene is considered the preferred route.
Cresylic acids are basically a mixture of cresols. These acids are usually obtained by the processing of coal tars, coal gasification or petroleum extracts. The availability of coal tars and petroleum caustic extracts has been reduced because of changes in technology, causing many isolators of cresylics to terminate their operations. Cresylic acids are used mainly as a feedstock for the isolation of cresols, xylenols and their mixtures, as well as in direct use as a solvent for wire enamels.
The following pie chart shows world consumption of cresols, xylenols and cresylic acids:
In 2007, world consumption of cresols, xylenols and cresylic acids was about 5% higher than in 2004. The major world consumers of cresols, xylenols and cresylic acids are the United States, Western Europe, China and Japan, representing roughly 87% of the 2007 world total. Moreover, China overtook Japan (based on total quantity consumed) to become the third-largest consumer of cresols, xylenols and cresylic acids by 2007. Demand for cresols, xylenols and cresylic acids is expected to grow at 6–7% per year in China during 2007–2012.
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