钾对低温耐硫变换催化剂的影响

Effects of potassium on the low temperature sulfur-tolerant water-gas-shift catalyst

采用不同钾源制备低温耐硫变换催化剂Mo-Co-K/Al_2O_3,通过XRD、N_2吸附-脱附法和微反评价等研究钾源对催化剂的钾流失率、孔结构及反应过程中钾硫酸盐化的影响。结果表明,以K_2SO_4为钾源的催化剂钾流失率最大,活性最低。KNO_3和KOH对拟薄水铝石的胶溶能力较强,易形成小孔径结构的催化剂。K_2SiO_3可以有效避免催化剂中钾在反应过程中的硫酸盐化。

Mo-Co-K/Al2O3 low temperature sulfur-tolerant water-gas-shift catalysts were prepared by using different K sources. The effects of K sources on K leaching and pore structure of the catalysts and K sulfation during the reaction were investigated by XRD,N2adsorption-desorption and catalyst evaluation. The results showed that the catalyst prepared by using K2SO4 as K source possessed the highest K leaching and the lowest activity. KNO3 and KOH exhibited stronger ability to peptize the pseudo-boehmite,which resulted in the formation of the catalyst with smaller pore structure. K2SiO3 could effectively avoid the sulfation of potassium in the catalyst during the reaction.