What is the difference between petroleum distillates and petrochemicals? Is one more toxic than the other?
Petrochemicals are any chemicals made from coal tar or crude oil. Petroleum distillates are petrochemicals that have been distilled in a refinery and then usually processed further and purified in some manner. There are many different types with completely opposite characteristics and uses. Distillation is the basic process used to separate and purify the components of crude oil. Crude oil is a complex mixture of hydrocarbons with impurities like sulfur, nitrogen and small amounts of metal. During distillation, the oil is heated in a large closed vessel called a still. The lighter components boil off first and rise to a higher point inside a tower above the still. The heavier components boil off at higher temperatures and condense back into liquids more quickly. These products are captured on trays at each level and pass out of the tower. The lighter and more volatile products are used in gasoline or as solvents, the next heavier might be used as diesel or stove oil and the next as lub
