With no recycle gas, doesn the catalyst coke up?
No, not if you keep a presence of excess hydrogen. The absence of recycle gas to keep sweeping through the catalyst is a new concept for refiners. However, recycle gas is not necessary to prevent coking in normal hydrotreating reactions–the presence of hydrogen is the important factor. The IsoThermingSM process assures that hydrogen is always present in the catalyst bed, thus reducing coking concerns.
