Abstract: An aromatic alkylation process comprising continuously feeding catalyst particles through at least one substantially vertically-positioned permeable tube disposed in a vessel surrounding said permeable tube, contacting said catalyst particles with at least one aromatic hydrocarbon and at least one alkylating agent under liquid phase alkylation conditions, continuously removing said catalyst particles from a lower end of said tube, and recovering said alkyl-substituted aromatic.

Abstract: An aqueous oxidation-reduction composition and method for removing hydrogen sulfide gas from a fluid stream by liquid phase oxidation of the hydrogen sulfide to elemental sulfur with a chelated polyvalent metal catalyst, such as iron, wherein the composition is stabilized against rapid loss of chelated polyvalent catalyst caused by contamination of the aqueous composition with micro-organisms, such as bacteria. The aqueous composition is stabilized by incorporating in the aqueous composition and adding throughout the normal usage thereof a broad spectrum biocide in an amount which acts as a bacteriostat to prevent rapid growth of bacteria in the aqueous composition and when the bacteria concentration rises above about 1.times.10.sup.6 colonies per ml.

Abstract: An aqueous catalytic oxidation-reduction composition for oxidizing hydrogen sulfide to produce elemental sulfur and a method of removing hydrogen sulfide from a gas stream whereby a gas stream containing hydrogen sulfide is brought into contact with an aqueous catalytic oxidizing reaction composition containing a water soluble polyvalent metal salt having the metal in the higher valent state and at least one surfactant, preferably a low foaming nonionic surfactant, such as a linear alcohol alkoxylate surfactant, which is adapted to wet the elemental sulfur formed and having the surfactant present in the reaction solution in an amount sufficient to prevent formation of sulfur froth on the surface of the reaction solution.