Abstract: A continuous process has been found for producing hydroxyacylated alkenyl-substituted mono- and bis- succinimides. The Mannich phenol coupled compositions are produced continuously as well. In the imidization reaction, an alkenyl succinic anhydride is contacted with a polyamine to form mono- and bis- polyamino alkenyl succinimides in continuous stirred tank reactor for a residence time of 1 to 3 hours. The reaction product is then, optionally Mannich base coupled. Finally, in the amidization, the mono- and bis- polyamino alkenyl succinimide is contacted with an acylating agent such as hydroxyacetic acid. Contacting is carried out in a continuous stirred tank reactor for a residence time of 3 to 6 hours. A hydroxyacylated alkenyl-substituted mono- and bis- succinimide product free of haze is produced in the absence of filtering, by reducing water continuously in all three reactors to a concentration of 0.4 wt %.

Abstract: Spent hydrotreating catalyst having carbonaceous and metallic deposits and of regular geometric shape after being stripped of process oil is fluidized by flowing air upwardly through the catalyst at a velocity sufficient to expand the bed thereby segregating the catalyst particles into a high activity, upper, less-contaminated fraction and a lower, more-contaminated fraction and recycling the high activity fraction to a hydrotreating process. Optionally, the high activity fraction can be regenerated with carbon burnoff or rejuvenated by acid leaching followed by regeneration with carbon burnoff to further improve catalyst activity.