Abstract: Sulfur oxides are removed from a gas by an absorbent which comprises an inorganic oxide composition in association with at least one free or combined rare earth metal selected from the group consisting of lanthanum, cerium, praseodymium, samarium and dysprosium, wherein said inorganic oxide composition is selected from the group consisting of MgAl.sub.2 O.sub.4, mixtures of alumina with magnesium oxide and mixtures of magnesium oxide with MgAl.sub.2 O.sub.4. The absorbent can be circulated through a fluidized catalytic cracking process together with hydrocarbon cracking catalyst to reduce sulfur oxide emissions from the regeneration zone.

Abstract: Extraction battery fouling is reduced in the solvent extraction purification of crude phosphoric acid by performing the steps of:(a) extracting crude phosphoric acid with solvent in a main extraction battery without the addition of sulfuric acid;(b) acidulating the raffinate from step (a) with at least a precipitate-forming amount of sulfuric acid;(c) aging the precipitate of step (b) for at least 15 minutes, and separating the precipitate from the acidulated raffinate;(d) extracting with organic solvent the essentially precipitate-free raffinate of step (c) in a secondary extraction battery.