Bionaphtha: The Renewable Alternative to Fossil-Based Naphtha
As the production capacity of renewable diesel (RD) and sustainable aviation fuel (SAF) grows, so will the output of the hydrotreated vegetable oil (HVO) process coproducts, including bionaphtha and biopropane. As with petro-based, biobased naphtha can be used as a gasoline blending component or a feedstock to make ethylene, propylene, and butadiene for chemicals and plastics.
Naphtha and its Applications
Petro-based naphtha is a hydrocarbon intermediate primarily produced from crude oil and constitutes 15% to 30% of crude oil feedstock. It is also produced from coal, shale oil, and tar sands feedstocks. Naphtha is a versatile and essential feedstock utilized to produce chemicals, fuels, solvents, plastics, ammonia fertilizers, olefins, and aromatics. Research and Markets estimates global production at over 300 M tonnes 1. The term naphtha is somewhat generic as many refineries process different crudes for many uses. However, the petroleum industry does distinguish two primary distillation streams, light naphtha C5 – C6 with a boiling point range of 30C – 90C (well suited for ethylene production) and heavy naphtha C7 – C9 with a boiling point range of 90C – 200C (used in blendstock for gasoline).
What is bionaphtha, and how does it compare to petro-based naphtha?
As illustrated in Figure 1, bionaphtha is a product of the hydrotreated vegetable oil (HVO) processes in producing renewable diesel and sustainable aviation fuel.
Figure 1.
Bionaphtha is considered more sustainable and can be utilized for most of the same purposes as crude oil naphtha. The HVO process destroys the triglyceride-producing propane and fully saturates the fatty acids. The deoxygenating step removes most of the oxygen. Because the p
araffin is saturated, most manufacturing processes include isomerization, producing iso-paraffins to improve cold temperature performance. Bionaphtha does differ from petroleum naphtha in that the HVO processes do not produce naphthalene (associated with coal, shale, and tar-based feedstocks) or aromatics and olefins (sometimes referred to as cracked olefins which are unsaturated). The latter two products can be produced using bio-naphtha through established manufacturing processes, such as cracking to make ethylene or propylene. While most current renewable diesel and sustainable aviation fuel manufacturers produce naphtha, the yield can vary considerably depending on the producer and the processes (3% - 30%). Many HVO processes yield naphtha with a hydrocarbon range of C5 – C8. Bionaphtha supply is projected to grow substantially as renewable diesel and sustainable aviation fuel capacity increases to meet demand driven by policies, regulations, and sustainability initiatives. North American production for HVO renewable diesel is expected to grow to 6 billion gallons by 2030.
In the United States, low carbon programs such as the Low Carbon Fuel Standard and Renewable Fuel Standard are driving the HVO demand and production. The bionaphtha produced in the US by companies such as World Energy is used in gasoline blends and products such as E 85 (a mixture of 15% naphtha and 85% ethanol). In the EU, market regulations such as RED II and consumer demand for plastics and chemicals from non-fossil feedstocks are driving bio-naphtha use.
Essentially, bionaphtha can replace petro-based naphtha in most applications. The ability to interchange the two products will accelerate the chemical industry’s sustainability goals to net-zero greenhouse gas emissions.
Sources:
1. Naphtha Market: Global Industry Trends, Share, Size, Growth, Opportunity and Forecast 2021-2026