| In this thesis, the iron oxide desulfurizer was prepared from converter steel-making mud, and it had a greater capacity of removing hydrogen sulfide (H2S) and carbonly sulfide(COS) from coking gas by modification. After the desulfurizer becomes invalid, it could be prepared into iron oxide red.In the process of desulfurizer preparation, the optimal operational conditions were: sulfur acid concentration 70%, reaction time 2 h, temperature 120℃, the dosage of hydrochloric acid 15 mL/10 g material(dry) and the dosage of assistant-solution agent 10.5 g/10 g material(dry). The highest iron extraction yield was 96.20%. The unmodified desulfurizer particles were yellow slender cylindrical, and they were characterized: strength greater than 50 N/cm, bulk density 0.70~0.80 g/ml, specific surface area 100~120 m2/g, porosity 42% and the size of the desulfurizer particleφ(3~5)×(5~15) mm. Under the conditions: H2S concentration in the feed gas 50 mg/m3, room temperature(25℃), 1 atm, space velocity 1000 h-1, moisture content 1% and oxygen free, the average effective sulfur capacity of the desulfurizer per one time was more than 10%.In order to improve the capacity of sulphurization from coking gas, the iron oxide desulfurizer was modified by immerging carbonate. Results showed that, under the conditions: H2S concentration in the feed gas 50 mg/m3, room temperature(10～30℃) , normal atmospheric pressure, space velocity 1000 h-1, moisture content 1% and oxygen free, the modified desulfurizer's capacity on COS was 3%, and that the desulfurizer could also remove more H2S. The alkaline hydroxy group on the active center surface could catalyze and hydrolyze COS into hydrogen sulfide, but FT-IR of modified desulfurizer showed that it was poisoned by sulfate which was oxided in the process of removing, and then it lose activity completely.The inactive desulfurizer could be recycled and prepared into iron oxide red. The technology was simple, and the purity of iron oxide red exceeded 99%.
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