催化裂化增产丙烯和烟气脱硫双功能助剂的热和水热稳定性

THERMAL AND HYDROTHERMAL STABILITY OF BIFUNCTIONAL ADDITIVES FOR IMPROVING PROPYLENE YIELD AND SOx REMOVAL OF FCC FLUE GAS

采用XRD、N2吸附、吡啶吸附红外光谱法研究了催化裂化增产丙烯和烟气脱硫双功能助剂的热和水热稳定性,分别在微反装置和烟气脱硫评价装置上对助剂的增产丙烯和烟气脱硫性能进行了评价。结果表明,仅对助剂进行热处理,其增产丙烯的效果与同条件下经过处理的工业增产丙烯助剂LTB-1的效果相当;而高温水热处理后,由于尖晶石中与分子筛发生离子交换的Mg2+对ZSM-5晶体结构造成破坏,增产丙烯效果受到严重影响。此外,水热处理后的双功能助剂仍然具有理想的烟气脱硫效果。

The thermal and hydrothermal stabilities of bifunctional additives for improving propylene yield and SOx removal of FCC flue gas were investigated by XRD,N2 adsorption and Pyridine-FT-IR.The performances of the bifunctional additives to FCC catalyst was investigated on a FCC micro fixed-bed reactor unit.Also,the uptake ability of SO2 was evaluated over the hydrothermal treated samples under the conditions similar to that of the FCC regenerator.The results showed that the activity of thermal treated bifunctional additives was comparable to that of the commercial propylene additive LTB-1 for increasing propylene yield.However,the activity of ZSM-5 in the hydrothermal treated samples for increasing propylene yield was greatly reduced,due to the ion-exchange of Mg2＋ with ZSM-5 zeolite.Moreover,the hydrothermal treated ZSM-5/MgAl2O4 bifunctional additive still exhibited satisfied uptake ability of SO2.