Catalysis 2024 Issue

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Borotec Borotec Valor

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Olens additive

Figure 6 Key results from Trial 3 of Valor technology

common contaminants found in FCC feeds, leading to losses in catalyst activity and increased coke and dry gas. Furthermore, operational measures to counteract these chal- lenges can be expensive or limited by unit constraints. It is not expected that vanadium or the associated challenges will go away as the refining industry continues to face pressure to operate flexibly and profitably. Thus, optimising an FCC catalyst system through vanadium passivation remains a key need for the present and the future. This and prior work show that more traditional vanadium passivation technologies can be highly reactive with SOx found in FCC regenerators. This then impedes the ability of the traditional trap to react with and passivate vanadium contaminant. However, the design of a more sulphur-tol- erant vanadium trap is possible. Multiple experimental and in-unit trials have shown that the inclusion of a more sul- phur-tolerant technology with FCC catalyst improves the catalyst tolerance to vanadium and that vanadium tolerance improves a refiner’s ability to reach a variety of goals. Trial 1 showed Valor + Fourte catalyst worked well together to preserve catalyst activity, enabling a reduction of slurry and an increase in butylenes yield. Trial 2 demonstrated that Valor + MPS technology led to increased FCC propylene yields using a lower ROT and less olefins additive despite higher levels of vanadium. Finally, Trial 3 described a case in which the FCC catalyst system did not change, but Valor led to increased activity without changing catalyst selectivity. Significant evidence from experimental work and in-unit trials should give FCC operators confidence that the right vanadium passivation technology can help FCCs achieve their goals. Corbett Senter is Regional Marketing Manager, Refining Catalysts, Europe, Middle East & Africa, at BASF. He holds a BS in chemical engi - neering from the University of Mississippi and a PhD in chemical and biomolecular engineering from Georgia Institute of Technology. Email: James.senter@basf.com David M Stockwell is a Sr. Principal Scientist at BASF Corporation. He holds a BS ChE from the University of Rochester and an MS and PhD from the University of Connecticut. Bingliang Liu is Regional Sales and Technical Service Manager for BASF’s refining catalyst business in Asia Pacific. He holds a degree in chemical engineering from the National University of Singapore. Benjamin O’Berry is Technical Sales Manager for BASF’s refining cat - alysts, UK and Northern Europe Team Leader. He holds a BS ChE from North Carolina State University.

impact a catalyst designed for propylene maximisation can make. While the slightly lower feed rate plays some role in increasing the conversion, it is significant that the Ecat vanadium and sodium levels increased by almost 30%. An increase such as this typically increases catalyst deactiva- tion, lowering the catalyst activity and ultimately lowering conversion in the FCC unit. However, the impact is counter- acted using strong vanadium passivation technology. The final trial example of Valor in an FCC unit took place in a European refinery operating at mild resid conditions. The unit used BASF’s Borotec catalyst, which was designed to enable the processing of mild-resid feeds by leveraging boron technology to passivate nickel. Boron is an especially effective way of passivating nickel as it is highly reactive with nickel contaminant, neutralising reacted nickel’s ability to produce hydrogen and coke, and has high solid-state mobil- ity – a key necessity since nickel contaminant itself is immo- bile once deposited on catalyst. The FCC previously held an objective to increase the yield of LPG olefin products, so a reduction in the rare earth on zeolite of the catalyst occurred. The rare earth change achieved the desired objective but resulted in reduced catalyst activity, as expected. This third trial describes the decision to add Valor vanadium passiva - tion technology to the catalyst system to improve catalyst activity through better vanadium tolerance and, therefore, increased zeolite retention, without losing the benefit gained from increased LPG olefin production. Figure 6 shows the results of the catalyst trial using Valor compared to the previous catalyst. At comparable metals levels, the catalyst system using Valor noticeably increased the activity of the catalyst system (Ecat activity vs vanadium and sodium). A second, equally important result of the trial is seen in the graph of LPG olefins yield vs olefins additive loading. The two trial catalysts show the same production of LPG olefins product at comparable olefins additive levels. Thus, this demonstrates once again that selecting the proper vanadium passivation technology can result in improved cat- alyst activity without altering the inherent product flexibility of the FCC catalyst. Conclusion Dealing with vanadium in feed continues to be one of the most important challenges for FCCs. It is one of the most

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