Preparation of α-FeOOH with different crystallinity and its low-temperature desulfurization performance.

Abstract

Crystal α-FeOOH and amorphous α-FeOOH were obtained at different preparation temperatures, and low temperature desulfurization tests were carried out respectively. The results were characterized by XRD, BET, FT-IR and UV-vis. When the preparation temperature is 10-20℃, α-FeOOH is a crystalline structure composed of large grains, and when the preparation temperature is -5-5℃, α-FeOOH is an amorphous structure composed of small grains. The results of desulfurization test show that the amorphous α-FeOOH desulfurizer prepared at 0℃ and the crystal α-FeOOH desulfurizer prepared at 15℃ both have high desulfurization performance. The desulfurization effect of α-FeOOH desulfurizer is related to the specific surface area and deactivation rate of the desulfurizer. Combined with inactivity mechanics analysis, the desulfurization performance of crystalline α-FeOOH is mainly affected by physical adsorption capacity, and the sulfur penetration capacity is proportional to the specific surface area. Amorphous α-FeOOH is mainly affected by the rate of deactivation. Because there are many micropores in the amorphous structure, it is easy to be blocked and deactivated by vulcanization products. The thermodynamic calculation results show that α-FeOOH is suitable for low temperature desulfurization. At high temperatures, the penetration sulfur capacity of α-FeOOH desulfurizer is close to the theoretical sulfur capacity, because hydrogen sulfide molecules can fully diffuse into the desulfurizer at high temperatures to react.