The method 1 further comprising regenerating the cerium promoted zeolite catalyst to {HEAD ~ a predetermined level} to form {TAIL ~ a regenerated cerium promoted catalyst} 
to form
The method 1 further comprising regenerating the cerium promoted zeolite catalyst to { HEAD ~ a predetermined level } to form { TAIL ~ a regenerated cerium promoted catalyst }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL