Industrial & Engineering Chemistry Research, Vol.53, No.21, 8874-8880, 2014
Desulfurization Behavior of Cerium-Iron Mixed Metal Oxide Sorbent in Hot Coal Gas
Ce-Fe mixed metal oxide sorbent C2F3B850 was prepared by using cerium oxide and red mud (an iron oxide waste from a steel company). The ability of C2F3B850 (CeO2/red mud = 0.85) was evaluated over a fixed-bed reactor in a simulated coal-derived gas. It was found that the main active components of sorbent C2F3B850 were cerium and iron oxides, the addition of red mud in CeO2-based sorbent could decrease sulfurization temperature, and 500 degrees C is the best temperature for sulfurization in the range of 500-700 degrees C. After eight successive sulfurization-regeneration cycles over C2F3B850, the regenerated sorbent still performed well with no apparent deterioration. The average breakthrough sulfur capacity corresponding to H2S concentrations below 50 ppmv is 9.97 (g S/100 g sorbent). Sorbent C2F3B850 during successive sulfurization-regeneration cycles was characterized by means of X-ray photoelectron spectroscopy, X-ray diffraction, and nitrogen adsorption-desorption techniques. The results reveal that the C2F3B850 sorbent with good durability, high efficiency, and high mechanical strength is suitable for desulfurization of hot coal-based gas in the chemical industry.