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Coal tar used as a raw material for PC is obtained by the dry distillation of coal and produced as a by‐product in the production of metallurgical coke used mainly in steelmaking and in the production of town gas. Useful application of coal tar is important for supporting the steel industries and fuel gas industries.

Production status based on data in 2009 is approximately as follows. In addition to use coal tar generated as a fuel, approximately 16 000 000 t of coal tar is fractionally distilled to produce the naphthalenes, tar acids, tar bases, creosote oil, and soft coal‐tar pitch (boiling point: 300 °C or more). The soft coal‐tar pitch is further distilled to raise the softening point to produce medium pitch (softening point: 60–80 °C) and hard pitch (softening point: higher than 80 °C). The ratio of each product produced is 10% for naphthalenes, 5% for tar acids, 5% for tar bases, 30% for creosote oil, and 50% for coal‐tar pitch including medium and hard pitches. Approximately 90% of pitch produced is used as an anode material for aluminum smelting, a synthetic graphite electrode for steelmaking, or a binder pitch for various carbon products. Remaining 10% of soft pitch (SOP) is used as a raw material for the thermal decomposition polycondensation reaction (carbonization) to produce both PC and creosote oil. The ratio of each product in production of PC is 10% for naphthalenes, 5% for tar acids, 5% for tar bases, 40% for creosote oil, and 40% for PC. The annual production volume of PC is estimated to be approximately 900 000 t.

Production sites and production process of PC are given in Table 6.1.3.1. An actual output of PC (estimated in 2009) in each region is estimated to be from 400 000 to 500 000 t/year in China, 280 000 t/year in Japan, 110 000 t/year in South Africa, and 50 000–100 000 t/year in Eastern Europe. Production of PC is particularly grown in China as the center where extensive economic development is under way.