Sulfidation of Iron-Based Sorbents Supported on Activated Chars during the Desulfurization of Coke Oven Gases: Effects of Mo and Ce Addition
2014
Yin, Fengkui | Yu, Jianglong | Dou, Jinxiao | Guptā, Suśīla | Moghtaderi, Behdad | Lucas, John
Coke oven gas cleaning is an important issue in China, where it can be a source of liquefied natural gas (LNG) through the methanation process. In this study, char-supported sorbents were prepared by loading iron, cerium, and molybdenum into a Chinese lignite through co-precipitation, and the sorbents were used for dry desulfurization of coke oven gases. Desulfurization efficiency of the sorbents was examined using a fixed-bed reactor in a temperature range of 473–673 K using a simulated coke oven gas. A gas chromatograph equipped with both a flame photometric detector (FPD) and a thermal conductivity detector (TCD) was used to analyze gas composition, while X-ray diffraction and scanning electron microscopy were used to examine chemical phases and the dispersion pattern of the active constitutes of the sorbents. The experimental results showed that the highest desulfurization efficiency and sulfur capacity appeared at 673 K. The reactivity of the nanosized active components in the char increased with increasing the desulfurization temperature in the temperature range of 473–673 K. In the case of Fe–Mo-impregnated sorbents, Fe and Mo combined together to form complex Fe–Mo oxide phases. The introduction of Mo in the sorbent is found to greatly increase the sulfur capacity and desulfurization efficiency of the Fe sorbent supported on activated chars. The addition of Ce leads to noticeable improvement of the performance of Fe sorbent during sulfidation. The mechanisms and factors influencing the sulfidation reactions have also been discussed.
显示更多 [+] 显示较少 [-]