Katasulf process

In the basic form of the Katasulf process, the gas was first passed through an electrostatic filter for tar removal and then preheated to 750°F by heat exchange with the gas leaving the catalytic converter. After addition of air, the gas was admitted to the catalyst chamber where the H2S was converted to SO2. Because of the exothermic nature of the reaction, the gas temperature increased considerably in the converter. The exit gas was partially cooled by heat exchange with the incoming gets. It was then passed through an absorption lower where ii was washed countercurrently with a concentrated aqueous ammonium sulfite-bisulfite solution, which absorbed both the SO2 and NH3. 

The preferred catalyst for the Katasulf process was composed of two metals—one (e.g., iron, nickel or copper) combined with the hydrogen sulfide to form metal sulfide, and the other (e.g., tungsten, vanadium, or chromium) served as an oxygen carrier. 

Katasulf A process for removing hydrogen sulfide and ammonia from coke-oven gas, developed by IG Farbenindustrie in Germany in the 1920s. The basic reaction involved is the catalyzed oxidation of hydrogen sulfide to sulfur dioxide and water at approximately 420°C ... 

---