ethylene with oxygen over an EO catalyst

EO overview

EO is formed by reacting ethylene with oxygen over an EO catalyst. The main competing reaction is the combustion of ethylene to CO2 and water. There is also a consecutive combustion reaction where EO further reacts to the combustion products (see reaction figure - right, top).

The goal of EO catalysis is to maximise the primary reaction (K1) while minimising or eliminating the competing and consecutive reactions, K2 and K3. CRI has been working in the area of EO catalysis for more than 40 years, constantly and consistently improving catalyst performance.

The most important measure of EO catalyst performance is selectivity-defined as the molar yield of EO produced per molar quantity of ethylene reacted. Another important parameter is activity, the catalyst temperature required to achieve a desired EO production level. CRI’s scientists have focused on improving not only the initial selectivity performance of our EO catalysts, but also the average catalyst selectivity throughout life.

CRI’s long-term success is built on a series of revolutionary scientific breakthroughs that have defined EO catalysis for over 40 years. CRI currently offers EO catalysts in four different families (see graph - right, bottom), all of which were first invented by CRI, clearly marking CRI as the world’s undisputed EO catalyst technology leader.

CRI remains active in developing, testing, demonstrating, and marketing future generations of industry-leading catalysts. Our goal remains the same as it has always been - to be the undisputed leader in providing superior EO catalyst products to the global EO industry.

Ethylene Oxide High Activity

High activity catalyst

CRI’s High Activity (HA) catalyst family has been in existence since the 1960s. An R&D breakthrough in 1972 led to the development of the modern HA catalyst. With many improvements over the years, CRI has a long history in providing HA catalysts to the EO marketplace.

CRI HA catalysts offer exceptional initial catalyst activity and long-term stability at reasonable selectivities. With many more than 300 charges of HA catalysts started up and operated all over the world, CRI is an industry leader in this catalyst family technology. However, with the invention of more selective catalysts by CRI, HA catalysts are typically only used by older EO processes that cannot take advantage of more modern catalyst families.

High selectivity catalyst

CRI revolutionised the EO industry when our first High Selectivity (HS) catalyst was introduced in 1987. HS catalysts offer superior selectivity compared to HA Catalysts, leading edge catalyst technology, and efficient plant operation.

HS catalysts have saved the industry thousands of kilotons in reduced ethylene consumption and reduced CO2 emissions. Over 25% of the world’s EO is made over CRI’s HS catalysts. With many more than 200 charges of HS catalyst operated and more than 20 years of operational experience, CRI is the unparalleled leader in HS catalyst technology.

Ghent Plant

Hybrid catalyst

While HS catalysts offer outstanding economic performance to customers, process constraints in some plants limit their use. Therefore, CRI scientists embarked upon an ambitious R&D program designed to unite the best features of both the HA and HS catalysts into a single catalyst. The result? CRI’s “Hybrid” (HY) Catalyst Family.

These catalysts feature much higher selectivity than HA catalysts, while retaining better long-term activity and stability than HS catalysts. Introduced in 2002, HY catalysts have quickly become accepted in the marketplace, with more than 60 commercial charges in operation. Once again, CRI has demonstrated its technical leadership in delivering winning technology to the marketplace.

High performance catalyst

High performance catalyst

The scientists at CRI were not content with a HY catalyst that was a “better” HA catalyst. They have continued to work on improving HY catalysts to compete with the best performance of HS catalysts. CRI is proud to announce the invention of a fourth catalyst family, the High Performance (HP) family of EO catalysts.

HP catalysts have initial selectivities approaching or in some cases equaling HS catalyst performance. HP catalysts feature the high stability of HA and HY catalysts, making them the longest lived, highest selectivity catalysts available in the world. First demonstrated on a small scale in 2005, CRI’s HP catalyst family is now poised once again to recalibrate what defines a world-class EO catalyst.

More in catalysts

Custom catalysts

CRI Catalyst Company LP, with its global resources in research and development (R&D), manufacturing, and surface and materials science is a highly desirable partner in custom catalyst development.

Environmental catalysts

CRI have catalysts that can work for your specific applications. Trained professionals will be able to work with you to determine which catalyst will meet your specific needs.

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