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Mar-2013

New step-out hydroprocessing technology

Haldor Topsøe has recently commercialised a new hydroprocessing technology designated HyBRIM. This production technology is launched eight years after we commercialised our first cobalt moly BRIM hydrotreating catalyst.

Henrik Rasmussen
Haldor Topsøe

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Article Summary

Over the past eight years, we have launched more than a dozen BRIM catalysts, which have all been well received in the marketplace. Haldor Topsøe has been on the forefront of technology discoveries in the hydroprocessing area for the past 30 years. In the late 1970s it was Topsøe’s researchers who discovered that the HDS activity correlated with the presence of the CoMoS’s active sites. In the 1980’s, we were the first to determine that sulphided CoMo/NiMo slabs could be prepared with reduced interaction with the alumina surfaces, thus doubling the activity of the sulphided metal slabs. Henrik Topsøe named these activity sites as Type I and Type II activity sites; the name that is today synonymous with high activity and low activity catalyst. In the early 2000s, Haldor Topsøe’s researchers, led by Henrik Topsøe, discovered the presence of yet another activity site on the basal plane of the CoMo/NiMo sulphided slab. Using scanning tunnelling electron microscopes, we were able to take pictures of these new activity sites, which we named brim sites as seen in Figure 1.

We learned that the electrons of the sulphur atoms located on top of the metal slab one atom layer in from the edge, have a much higher density than other sulphur atoms on the basal plane. These high density sites with almost a metallic character, illustrated in Figure 1 as the yellow glowing circle on the basal plane are named the brim sites. The difficult sulphur and nitrogen species will be captured by these high density electronic structures, and the brim sites are responsible for the first stage of the hydrogenation route, depending on the operating pressure. The brim sites also plays a key role in the denitrogenation reactions which for the most refractive nitrogen compounds precede the hydrogenation route. The brim sites are, in general, much more active for the removal of the most refractive sulphur species in both diesel and gas oil fractions than the Type I and Type II activity sites. The Type II direct desulphurisation sites are located on the edges of the sulphided CoMo/NiMo slabs. These CoMoS/NiMoS sites are responsible for the final sulphur extraction.

Topsøe’s latest discovery designated HyBRIM, is an improved production technique for both CoMo and NiMo hydrotreating catalysts. It combines the BRIM technology with an improved catalyst preparation step. The combined effect from merging the two technologies leads to a metal slab structure that is characterized by an optimal interaction between active metal structures and the catalyst carrier.

As mentioned, the activity of the Type II sites is strongly influenced by this interaction between the metal slab and the carrier. The HyBRIM technology affects this interaction and results in a substantial increase in the activity of both the direct sites and the hydrogenation sites. Furthermore, the HyBRIM catalyst exhibits the same high stability as all our clients have experienced with the last two generations of BRIM catalysts.

Figure 2 shows the Topsøe developments in hydroprocessing technology over the past 30 plus years.

The improved HyBRIM technology has been applied to the production of our latest catalyst development called TK-609 HyBRIM. This catalyst is designed for use in hydrocracker pretreatment services as well as high pressure ultra low sulphur diesel services. The TK-609 HyBRIM catalyst exhibits a step-out activity improvement of approximately 40% compared to our previous NiMo, TK-607 BRIM, catalyst, corresponding to a 13°F to 15°F lower start-of-run temperature for otherwise unchanged conditions. The pilot plant test data in Figure 3 compares TK-609 HyBRIM with TK-607 BRIM in ultra-low sulphur diesel service.

Figure 3 shows that, at equal operating conditions, the product sulphur is reduced by about 15 ppm. Furthermore, it shows that the required temperature to maintain 10 wt ppm product sulphur is 13°F (7°C) lower for the new catalyst.

In hydrocracker pretreatment service, the product nitrogen for TK-609 HyBRIM, at equal operating conditions, is approximately 40 wt ppm lower and a similar drop in product sulphur is observed. A product nitrogen of 15 wt ppm can be obtained at a 15°F (8°C) lower operating temperature for TK-609 HyBRIM compared to TK-607 BRIM (Figure 4).
The step-out activity for TK-609 HyBRIM can be used to:
• Achieve longer cycles at the same feed rate
• Process more difficult feeds
• Increase conversion (volume swell)
• Increase throughput.

Any of these operating scenarios will significantly improve the profitability of our clients.

Since the introduction of our BRIM catalysts, Topsøe has sold more than 200 million pounds of these high-activity, Type II catalysts in the marketplace. With the improved HyBRIM technology, we will be able to continue to launch more active hydrotreating catalysts for all high-severity hydrotreating applications in the near future.


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