Catalysis 2022 issue

streams to decarbonise fuels and chemicals production, and grow chemicals production as fuels demand declines, thus reducing Scope 3 emissions. In addition, as an oil refinery increases its percentage of chemicals production, the refin - ery margin tends to increase. For some time now, oil refiner - ies have been including bio-com- ponents in fuels production; the bio-component is typically added at the fuel blending stage. For exam- ple, Valero Corporation produces bioethanol on a large scale in the US. 4 Globally, bioethanol is pro - duced from corn, wheat, sugarcane, beetroot, or similar, and is a popular choice for decarbonising gasoline production. Different solutions are available for diesel. For example, Johnson Matthey’s biodiesel pro - cess uses fatty acids, obtained from the hydrolysis of bio-based oils, and converts them to fatty acid methyl esters (FAME, typically a mixture of several esters). See Figure 2 for a process flowsheet. So far, we have licensed eight plants globally. Furthermore, renewable diesel, a hydrocarbon diesel fuel produced by hydroprocessing of fats, vegeta - ble oils, or waste cooking oils, can be used as a direct substitute for conventional diesel fuel. Several units have recently been built in the US. As an alternative to green blend- ing components, bio- and waste

Methanol recovery

Fatty acid

Steam Oil hydrolysis pre-treatment

Water euent

Esterication

Oil

Biodiesel

Methanol removal

Methanol

Glycerol/water

Figure 2 Davy biodiesel process

streams can be used as a feedstock to produce gasoline and diesel. A low capital option involves using existing hydrotreaters to co-pro - cess bio- and waste streams to make fuels and olefins, which are partially green. Leading-edge oil refiners have been exploring this opportu- nity for some time and have dis - covered it is possible to co-process up to 10-20% bio- and waste com- ponents. For example, Parkland Corporation’s Burnaby refinery has successfully converted canola oil and oil derived from animal fats to fuels. 4 In addition, a growing num- ber of fluid catalytic cracking (FCC) units are exploring co-processing. For example, Preem AB Lysekil refinery has successfully converted biomass-based pyrolysis oil to fuels and olefins. 5 Another way to decarbonise fuels and chemicals is to convert munic- ipal solid waste and other renew- able biomass to low carbon fuels. For example, the FT CANS Fischer- Tropsch technology developed by Johnson Matthey in collaboration

with bp converts synthesis gas into long-chain hydrocarbons. The resulting FT products need upgrad- ing, which can be done by an oil refinery, to produce low carbon gas - oline, diesel, and jet fuels. Fulcrum is employing the FT CANS technol - ogy in its new Sierra BioFuels plant located in Nevada, USA. The Sierra plant is the first commercial-scale plant in the US to convert munic- ipal waste that would otherwise be sent to landfill, into a low car - bon synthetic crude oil (syncrude). Fulcrum plans to sell the syncrude to nearby oil refineries. The syn - crude can be used to reduce the car- bon intensity of transportation fuels. Furthermore, Johnson Matthey and MyReChemical have commercially developed a ‘waste-to-methanol’ technology. The methanol derived from this process is an important intermediate product used to pro- duce many goods that play a vital role in everyday life, such as res - ins, plastics, insulation, and fibres. Besides, the methanol can be used to decarbonise fuels too; for exam-

Product

Hydrogenation

Derivative

Hydroformylation (LP Oxo )

Coatings/adhesives Solvents PVC

n-butanol (n-BuOH) i-butanol (i-BuOH) 2-ethylhexanol (2EH)

DOP/DEHP

Propylene Syngas

n-butyl acrylate

Butyraldehyde

FT C Syngas Butene Syngas

PVC

Valeraldehyde

2-propylheptanol (2PH)

DPHP

Co-monomer

C aldehyde

Octanol

Octene-1

Dimeri s ed butenes Syngas

PVC

C aldehyde

Isononyl alcohol (INA)

DINP

Mixed FT olens Syngas

Detergents

C – C aldehydes

C – C alcohols

Figure 3 The feedstock flexibility of LP Oxo processes

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