Answer: cracking of naphtha. It is important to ensure that the feedstock does not crack to form carbon, which is normally formed at this temperature. This is avoided by passing the gaseous feedstock very quickly and at very low pressure through the pipes which run through the furnace Shale naphtha is obtained by the distillation of oil produced from bituminous shale by destructive distillation. Petroleum naphtha is a name used primarily in the United States for petroleum distillate containing principally aliphatic hydrocarbons and boiling higher than gasoline and lower than kerosene.
Explanation: Light naphtha can refer to either a finished product used as a petrochemical feedstock or a distillation cut commonly called light straight run naphtha. It is composed of pentane and slightly heavier material. In a refinery, light naphtha is often blended directly into gasoline.