PTQ Q2 2024 Issue

2.5

Standard Technology-20% SBO vs Standard Technology-VGO ReNewFCC - 20% SBO vs Standard Technology-VGO

1.5

Gasoline

Dry gas

0.5

LCO

Coke

650F+

LPG

-0.5

-1

-1.5

Iso-Conversion = 74 wt%

-2.5

Figure 3 Delta yields during co-processing of 20 wt% soybean oil in VGO for Ketjen’s baseline max olefin catalyst technology and ReNewFCC formulated for max olefins

FCC co-processing of WPOs Many waste plastic oils (WPO) are characterised by a high naphtha content. Depending on its composition, this naphtha may crack into lighter products or, in the case of aromatics, more likely remain in the naphtha fraction. As previously discussed, the composition of the WPO is highly dependent on the waste plastic source and the conversion technology. Figure 3 in Part I ( PTQ Catalysis 2024 ) showed an exam - ple of a simulated distillation curve for various WPOs and major hydrocarbon compounds within the various oils. Comparing WPO from polypropylene (PP) and polysty - rene (PS) clearly indicates that a large fraction of both is within the naphtha range. However, the PP-WPO is pri - marily comprised of iso-olefins, while styrene derivatives are prevalent in the PS-WPO. Generally, aromatics will not undergo catalytic cracking beyond cracking alkyl side chains, while olefins and paraf - fins can crack further into lighter components or cyclisation to aromatics. This is an important factor to consider when comparing the impact on product distribution during the co-processing of different types of WPO. Catalyst selection During catalyst selection for conversion of WPO co-pro - cessing applications, product distributions at constant conversion can be misleading. Conventional FCC feeds are primarily comprised of heavy boiling compounds, generally in slurry and, to a lesser extent, LCO boiling ranges. Thus, conventional conversion is often calculated and reported as 430F+ conversion by the yields of products not within LCO and slurry cuts (430F+ conversion = 100 – LCO% – slurry%). For example, in the co-processing of PP-WPO and PS-WPO over a baseline catalyst technology, bottoms yields may appear equal or higher compared to VGO pro- cessing, as shown in Figure 4 (top). However, this is just the effect of overestimating the conversion. Furthermore, it is unclear if the observed increase in gasoline is due to the addition of naphtha to the feed. To avoid this, we define an effective conversion.

gas. To achieve further valorisation of co-processing soy- bean oil and leverage the conversion chemistry, that cata- lyst can be further tailored. ReNewFCC technology is designed to maximise deoxy- genation and can be formulated to increase gasoline and gasoline range olefins. At the same time, coke and bottoms yields are reduced to maximise FCC unit profitability. This is achieved by controlling the adsorption of oxygenated molecules to balance deoxygenation mechanisms, reducing hydrogen transfer to avoid olefins saturation, and reduction of dehydrogenation reactions that lead to the conversion of olefins to aromatics and coke. Figure 2 provides an example of how the various grades of ReNewFCC formulated to maximise gasoline can influ - ence the removal of oxygen when co-processing canola oil in VGO. With increased decarboxylation, reduced dehy- dration and hydrodeoxygenation (as evident by increased oxygen removal as CO₂ and H₂O), oxygen can be removed while minimising hydrogen loss from the product. While unique feed-feed interactions and unit constraints should be considered, the know-how for manipulating deoxygenation was applied to the previous case for co-pro- cessing 20 wt% soybean oil. Figure 1 compares the addi- tional changes in the product slate that ReNewFCC can bring through the modification of deoxygenation pathways. Compared to the standard catalyst technology, ReNewFCC can significantly improve gasoline make while further reducing coke, LPG (featuring improved olefinicity), and dry gas. Maximising light olefins Alternatively, for units that target the light olefins produc - tion (C₄=, C₃=, and C₂=), ReNewFCC can also be formulated to maximise propylene with catalytic components that lead to the maximisation of cracking from gasoline to light ole - fins while maintaining the deoxygenation functionality. Figure 3 compares how the performance of a standard max olefin catalyst system can be further improved to increase gasoline conversion to light olefins while improving overall LPG olefinicity.

PTQ Q2 2024