The heart of a petroleum refinery ( fig . 1 ) is the " cracking " unit , which breaks high - molecalar - weight hydrocarbons into volatile compounds , convertible to gasoline by processes such as catalytic alkylation and reforming ( 3 ) 一個石油精煉廠的中心是裂化車間,在那里大分子量的碳?xì)浠衔飻嗔殉蔀榫哂袚]發(fā)性的化合物,這些化合物經(jīng)過催化烷化和催化重整可以轉(zhuǎn)化為汽油。