Coal tar can be injurious to health. Coal tar is also used to manufacture paints, synthetic dyes (notably tartrazine/Yellow #5), and photographic materials. In the coal gas era, there were many companies in Britain whose business was to distill coal tar to separate the higher-value fractions, such as naphtha, creosote and pitch. A great many industrial chemicals were first isolated from coal tar during this time. These companies included: Side effects of coal tar products include skin irritation, sun sensitivity, allergic reactions, and skin discoloration. It is unclear if use during pregnancy is safe for the baby and use during breastfeeding is
Coal liquefaction industrial scales (i.e. thousands of barrels/day) a coal liquefaction plant typically requires multibillion-dollar capital investments. A number of carbonization processes exist. The carbonization conversion typically occurs through pyrolysis or destructive distillation. It produces condensable coal tar, oil and water vapor, non-condensable synthetic gas, and a solid residue - char. One typical example of carbonization is the Karrick process. In this low-temperature carbonization process, coal is heated at to in the absence of air. These temperatures optimize the production of coal tars richer in lighter hydrocarbons than normal coal tar. However, any produced liquids are mostly a by-product and the main