Cracking catalyst additives for sulfur removal from FCC gasoline

FCC catalyst additives for sulfur-compound cracking with the ability to reduce sulfur in gasoline have been produced by depositing various metals and metal oxides on different supports using the microemulsion technique. Three groups of additives have been studied. First. Zn on different supports: alumina, titania, and hydrotalcite. Second, different metals on alumina: Zn, Mn and Zr, and third, two different metals on hydrotalcite: Zn and Co. The additives were blended to 10 wt% with a reference FCC-catalyst. All the additives give lower yields of gasoline than the reference catalyst itself. The loss in gasoline is due to an increased amount of gas production and/or increase in coke production. Concerning the sulfur reduction, the order of activity of the four best additives is the following: Zn/hydrotalcite > ZrO/alumina > Zn/titania > Mn/alumina. Zn/hydrotalcite has a value of approximate to 80% reduction of sulfur in sulfur-spiked gasoline at the microactivity test (MAT)-level. (C) 1999 Elsevier Science B.V. All rights reserved.