Seems like to me they could introduce magnetic fields into the refining towers to get the iron and nickel contaminants out of the processes so the catalysts will last longer..........
Interesting idea. I would think that a finer grind on the catalytic particles are not trying to go for a porous structure would solve the issue to but then you have the problem of trying to separate the catalyst back out of the oil.
If it’s the pellets getting coated on the outer surface, mechanical abrasion could help.