During the chemical reactivation process, the catalyst is initially supplied with essentially two major activity components:

The necessary or basic activity to achieve the required NOx reduction performance at initial operation, and
Additional or useful activity to allow the specification duty to be met through some useful life.
These are depicted in the Ko (original activity) bar of the graphic below as the gray and red regions, respectively. Aging of the catalyst reduces the useful activity through channel plugging by ash, and by the blinding of the active sites on a microscopic scale by fuel constituents and other fuel-related poisons that attach to active sites, chemically deactivating or sealing them and rendering these sites impotent. These deteriorating factors reduce the catalyst activity until the useful life has been depleted. At that time, the catalyst must be replenished, either through the purchase of new replacement catalyst or through regeneration. Replacement is a more costly alternative and results in disposing of the basic activity still left in the catalyst. Regeneration, on the other hand, fully restores the useful activity of the spent catalyst, while still taking full advantage of all the basic activity, for significantly less cost than replacement. By increasing the number of catalytic sites available for reaction, SCR-Tech's process has even been demonstrated in certain cases to increase catalytic activity beyond the original level by as much as 25%, providing the potential for significant economic upside.

Activity Often Enhanced Beyond Original

Once regenerated, SCR-Tech returns the catalyst modules to the customer for reinstallation in the SCR unit. Upon reinstallation, the long-time deactivation rates and NOx reduction performance of regenerated catalyst have proven to be essentially identical to new catalyst.