Petrochemicals are chemical products derived from petroleum, although many of the same chemical compounds are also obtained from other fossil fuels such as coal and natural gas or from renewable sources such as corn, sugar cane, and other types of biomass. Petrochemical production relies on the multi-phase processing of oil and associated petroleum gas. Key raw materials in the petrochemical industry include products of petroleum oil refining. Petrochemical goods include; ethylene, propylene, and benzene; source monomers for synthetic rubbers, and inputs for technical carbon. Petrochemical and petroleum products are second-level products derived from crude oil after several refining processes.