craquage du pétrole

OBS: craquage : Procédé de raffinage du pétrole qui consiste à fractionner les grosses molécules lourdes en molécules plus petites.
PHR: Craquage catalytique, thermique du pétrole.

OBS: [This method] originated about 50 years ago by the still men in the old Pennsylvania refineries and means just what its connotation conveys, namely a part alteration, as distinguished from the more complete decomposition which would disrupt the molecule largely into carbon and permanent gas. Cracking simply alters the molecules to an extent that produces an amount of low-toiling fractions that can not be obtained by simple distillation.
PHR: Catalytic, thermal cracking of oil.