Catalysis 2023 Issue

electrical energy that may not be all green and has its own pollution problems from ash and other materials. Further, these facilities are expensive to set up, operate, and main- tain. KBC believes the energy transition will take time. Thus, FCCs will play a significant role in the C3= olefin production market while co-existing with alternative pathways. Q What are some of the optimal strategies for process- ing (or co-processing) second- and third-generation renewable feedstocks? A Sophie Babusiaux, Hydroprocessing Technology Advisor, sophie.babusiaux@axens.net, Axens Lucas Vergaras, Principal Technology Engineer, lucas.verga- ras@axens.net, Axens Processing and co-processing renewable feedstocks is part of today’s main refineries’ strategies to reduce the carbon footprint of their activities. As defined by the European Union, second- and third-generation biofuels are produced from feedstock that does not compete directly with food and feed crops, such as wastes and agricultural residues (wheat straw, municipal waste), non-food crops (miscan- thus and short rotation coppice), and algae. The starting point strategy to integrate these feeds into a refinery is first to identify the local availability and indi - vidual feed challenges. Then, depending on the conversion/ hydroprocessing platforms available at site, look for the most suitable unit to cope with these in terms of existing hardware and impact on products. To be sure, more than 50 years of providing solutions in optimising refinery refin - ing schemes throughout the world delivers the repository of experience, know-how, and methodology to conduct detailed dedicated studies in a constantly evolving legisla- tion framework. Processing second- and third-generation biofeeds rep- resents specific challenges to the operation, for both new units and retrofits, either in co-processing or stand-alone mode. The design shall consider robust and proven solu- tions. We have developed solutions over the past 30 years to prevent pressure drop, loss of activity, corrosion, and other nuances that have emerged in the processing of renewable feedstocks. A Steve DeLude, Becht Advisor, sdelude@becht.com The optimal strategy is dependent on each site’s specific configuration, level of exposure to GHG emission-related costs (penalties) and/or biofuel production incentives, the logistical considerations related to the available biomass Processing second- and third- generation biofeeds represents specific challenges to the operation, for new units and retrofits, either in co-processing or stand-alone mode

feedstocks, the cost of the feedstock, and corporate capital availability/investment hurdle rates. The mandates of the Paris accord established require- ments for carbon intensity and GHG emission reductions that impact energy firms, regional/national governments, and investors. As part of the transition to lower emissions, traditional fossil fuel-based transportation fuels will be substituted by a combination of electric vehicles and bio- derived and renewable fuel sources. Existing refining and petrochemical assets are seen as key infrastructure in the energy transition equation, as much of the existing pro- cessing and distribution infrastructure can be repurposed for this new reality. This change in the marketplace will drive traditional refin - ers to examine processing and configuration options to align with the new feedstock and product profile, as well as energy input options. Those entities that are able to meet the changes in this dynamic market while remaining profit - able will continue as long-term viable enterprises. Biofuel- related strategies seen in the industry range from: • Full biofuel integration with dedicated biofuel units pro- viding fully fungible final product blend components • Partial integration and co-processing approach with bio- feeds brought on-site and pretreated adequately to match with the site’s existing units. • Third-party pretreatment arrangement or an owned, dedicated facility with feed specifications strictly monitored to ensure meeting co-processing/blending requirements • Purchase of biofuel blend components via open market • Purchase of GHG offsets from other entities. Finding an optimal strategy requires fully analysing each specific situation and identifying the range of options that could achieve the desired business goals. The progression of biofuel processing technologies from the current level to those in development is more catalyst- related than process-related. The steady progression of catalyst advancements has improved hydrogen selectivity and isomerisation to final products. As catalyst technologies further improve, opportunities exist for processing more challenging feedstocks and moving from biofeeds in com- petition with food sources to those which are non-edible. Europe’s Annex IX describes some of these bespoke bio - feeds, with consideration given to the use of non-edible cover crops using non-food-producing lands. The chang- ing feedstock quality imposes increasing levels of contami- nants and lower carbon contents. Processing these feeds requires consideration of how to remove the contaminants (including water) and capture the maximum amount of hydrocarbon products. The future transition to these new feeds requires con- sideration of thermal pretreatment processes linked with refinery post-treatment to make fungible fuels. (For addi - tional details, see Sayles and Ohmes, Conversion to a green refinery, Decarbonisation Technology , Nov 2022). Refinery configuration and biofeed considerations determine the ease of integration. In general, more complex refineries offer greater opportunities for biofeed integration. In conclusion, the consideration of co-processing is depen - dent on the refinery configuration, feedstock selection,

Catalysis 2023