Which one of the following is not a product of petroleum?

CNG (Compressed Natural Gas) is not a product of petroleum refining; it is obtained from natural gas reserves, which are separate from petroleum (although sometimes found together). Kerosene, paraffin wax, and bitumen are all fractional distillation products obtained from crude petroleum. Kerosene is used as fuel, paraffin wax in candles, and bitumen for road surfacing.