EHC 340 MAX™: The cutting edge of base stocks

Not all base stocks are created equal. Depending on their viscosity, volatility and saturate level, among other features, some are better suited for certain applications than others. With this in mind, it is not surprising that the automotive and industrial lubricants marketplace has seen growing demand for high-viscosity base stocks that remain stable when used in heavy-duty applications. As ExxonMobil Principal Engineer Bob Duggal said, “Extra heavy neutral base stocks are needed for industrial gear oil, automotive gear oil, greases, engine oil and marine oil. You cannot create high-viscosity and quality lubricants without them.”

Lubricant formulators typically turn to Group I bright stocks to meet certain viscosity requirements, but, in doing so, they often have to sacrifice other product features like low-temperature performance. This is because there is currently no Group II or Group III base stock on the market that provides superior oxidative stability and wide temperature range of performance while matching Group I bright stock viscosity needed by the market. However, that is set to change in 2025 when ExxonMobil introduces its new extra heavy neutral Group II product, EHC 340 MAX™.

EHC 340 MAX™ will fill an important gap by combining the high viscosity of a Group I product with the better low-temperature performance and oxidative stability of a Group II product. It also has more saturates and less sulfur than Group I bright stocks, which is ideal given the increasingly stringent lubricant and oil regulations such as the International Maritime Organization’s sulfur cap.

In certain applications, EHC 340 MAX™ even has the potential to diminish or eliminate the need for a viscosity modifier. For example, a Group I bright stock used to blend an industrial grade oil could easily be replaced by a high-quality Group II base stock. Instead of having a tank filled with a Group I and another tank filled with a Group II, formulators would need only one tank filled with an extra heavy neutral like EHC 340 MAX™ to successfully blend their lubricants. This possible efficiency would not only reduce complexity for manufacturers but could also translate into cost savings.

“In short, EHC 340 MAX™ can help lubricant blenders minimize production costs and complexity while maximizing product performance,” noted Duggal, who currently leads global sales and marketing technical support for ExxonMobil Basestocks.

Given the widespread appeal of a base stock like EHC 340 MAX™, many may wonder why such a product has not been developed before. Simply put, high-viscosity Group II base stocks are not as easy to manufacture as low-viscosity ones — and high-viscosity base stocks with superior oxidative stability and broad temperature performance are even more difficult to produce.

Most Group II products have a kinematic viscosity of no more than 12 centistokes (cSt) at 100^oC, whereas Group I bright stocks can have a viscosity upwards of 30 cSt at 100^oC. A higher centistoke generally means more processing is required during base stock production, and additional treatment often means increased complexity and higher costs.

“There was no real product out there that was a Group II — which has better oxidative stability and good low-temperature performance — in the extra-high-viscosity space,” Duggal pointed out. “Before EHC 340 MAX™, there was a tension between the need for that kind of product and the difficulty in producing such a product.”

Ultimately, increased demand and technological advancements over the past decade have made it possible for ExxonMobil to both develop EHC 340 MAX™ and bring it to market on a global scale.

While commercial production won’t start until 2025, the product has been years in the making. We’ve been working on the project for the better part of a decade, with scientists and engineers starting with what Duggal called a “high-intensity development plan” in a “high-intensity analytical and modeling environment.” From there, the project moved to Houston, where a more advanced process design took place.

The integrated refining and petrochemical complex has feedstock and a proprietary catalyst system that allows the company to upgrade bottom-of-the-barrel products to higher-value lubricant base stocks like EHC 340 MAX™. Following years of testing, ExxonMobil experts have determined that the site is fit for purpose and has the technical readiness to deploy the new product at scale by 2025.

In addition, demand for high-performance base stocks is especially high in Asia, making the company’s location choice even easier. “Overall, this is a kind of puzzle that’s fitting together. And it’s something that’s unique to Singapore,” noted Duggal.

With an anticipated start date in 2025, the Singapore Resid Upgrade Project will bring EHC 340 MAX™ online at the perfect time. While demand for extra heavy neutral base stocks is resilient, supply could be impaired since many Group I bright stock plants are older and becoming less efficient. Once up and running, the Singapore Resid Upgrade Project could meet 10-12% of global demand for high-viscosity bright stocks, taking some of the pressure off these facilities.

Duggal noted how the team is making impressive progress on both construction and product development. “It’s very exciting to see that they’re putting the equipment we’re going to need on the ground in Singapore. We’re making some extremely heavy lifts. Every day something new is happening.”

In addition, the capabilities for EHC 340 MAX™ are continuously expanding. “Knowledge of how this base stock can be used is growing. Initially we only had preliminary performance data for the product. Now we have more detailed value-in-use information on how it can be used and how it can help our customers, who are getting more and more excited because we always have something new to share with them,” said Duggal.

Ultimately, the lubricants industry needs more flexibility and versatility from their base stocks, and that is exactly what EHC 340 MAX™ can provide. It combines the high viscosity of a Group I with the stability and performance of a Group II, all while potentially reducing costs and complexity for lubricant formulators. ExxonMobil’s customers need a product that can do it all, and EHC 340 MAX™ is one step closer to achieving that.