Biorefinery platforms – Oils
Concept
- The oils platform covers triglycerides that can be obtained from terrestrial oil plants (palm, coconut, rape seed, sunflower, soybean), aquatic biomass (microalgae), animal fats, industrial by-products (tall oil) and used oils (industrial and household).
- Oils and fats are esters composed of molecules known as triglycerides, which are esters composed of three fatty acid units linked to glycerol.
- Fatty acids gives the functionality to oil and fats. Chemically, they can be divided into four main types: saturated, cis-monounsaturated, cis-polyunsaturated and trans fatty acids. In broad terms, saturated fatty acids and trans fatty acids are solid at room temperature while the cis-unsaturated are liquid at room temperature.
Applications
- Biofuels. The primary feedstocks currently used to make biofuels are crude palm oil, rapeseed oil and soybean oil. But the utilization of industrial by-products and used oils is gaining ground. The majority of this biofuel market was traditional biodiesel (FAME, triacylglycerol molecule is converted to alkyl esters and glycerol by transesterification), but the share of HVO (hydrotreated vegetable oil) is increasing very rapidly, with a special focus on sustainable aviation fuel (SAF).
- Chemicals. The triacylglycerol molecule can be cleaved to glycerol and fatty acids. The usage of the fatty acids is determined primarily by their chain length and functionality. The majority of fatty acid derivatives are used as surface active agents in soaps, detergents and personal care products. Important products of unsaturated oils include alkyd resins, linoleum and epoxidized oils. In applications such as lubricants and hydraulic fluids, plant oil can act as direct replacement for mineral oil or require only minor chemical modification. Glycerol finds application in several sectors (food industry, pharmaceutical, personal care…).
- Biobased naphtha. It is one of the co-products that can be obtained via hydrogenation. It can be considered as a specific platform (Biorefinery platforms – Biobased naphtha).
- Biobased plastics. Sebacic acid and 11-aminoundecanoic acid (from castor oil) and azelaic acid (from oleic acid) are building blocks for biobased plastics. Dimerized fatty acids are primarily used for polyamide resins and polyamide hot melt adhesives.
References
- IEA Bioenergy Task 42 (2020). “Biobased chemicals. A 2020 update”.
