Noun
English Wikipedia has an article on:petroleum cokeWikipedia
petroleum coke (countable and uncountable, plural petroleum cokes)
A substance, mostly carbon, that is a byproduct of oil refining; used as a fuel or in many industrial applications.
Petroleum coke and sulphur by-products will be loaded onto ships at Kitimat if a bulk marine terminal is available or shipped by rail to Ridley Island at Prince Rupert for loading. Source: Internet