Abstract: A system of apparatus is especially adapted to react gaseous contaminates of natural gas streams with a slurry of reactant particles and incorporates a contactor tower with a bottom gas inlet having a screen at its dynamic liquid level to confine downwardly a fill of packer-spacer material. Gas entering through the bottom inlet of the tower is divided by the packer-spacer material in tortuous flow paths maintained by the confining screen.In advance of the contactor tower, after an inlet scrubber, is a heater which elevates the temperature of the gas before it enters the contactor tower. This avoids formation of clogging hydrates and liquefication of the gas. Using an outlet scrubber assures against entrance of droplets of any liquid into the pipeline.

Abstract: Substantially dry iron oxide particles having a high surface area, a high kinetic "K" value and composed of a crystalline phase of Fe.sub.3 O.sub.4 together with an amorphous Fe.sub.2 O.sub.3 moiety or portion and having a surface area of at least 4 m.sup.2 /.sub.g are useful for scavenging hydrogen sulfide from other gases containing it. A cartridge type device is provided containing such particles intermixed with inert particulate matter, e.g. sand, useful as a means for scavenging hydrogen sulfide from such other gases.

Abstract: Iron oxide particles composed of a crystalline phase of Fe.sub.2 O.sub.3, Fe.sub.3 O.sub.4 and combinations thereof together with an amorphous Fe.sub.2 O.sub.3 moiety or portion and having a surface area of at least 3.5 m.sup.2 /g are useful for scavenging hydrogen sulfide from substantially anhydrous non-aqueous liquids, particularly substantially anhydrous hydrocarbon liquids, for example, kerosene.