磷盐的钝镍作用及其机理的研究

Nickel-passivating effect of non-toxic P- containing salts and the mechanism

本文通过 MAT、TPR、XRD等实验方法和量化计算系统研究了某种无毒磷盐 (简称为 PNP)对 FCC沸石催化剂上沉积镍的钝化作用及其机理。结果表明 ,由于氧化磷和氧化镍在 FCC再生条件下反应生成 Ni P4 O11,增加了 Ni2 +的 LUMO能量 ,使镍在 FCC反应条件下更难被还原 ,因此 ,添加适量的 PNP可以有效地抑制 FCC沸石催化剂上 0价镍的脱氢生焦活性 。

The nickel passivating mechanism of non toxic P containing salts(PNP)is investigated using NAT,TPR and XRD combined with quantum chemistry calculation.Results show that new compound NiP 4O 11 forms after adding PNP to nickel deposited zeolite under the condition of FCC regeneration.Because LUMO energy of NiP 4O 11 is much higher than that of NiO,NiP 4O 11 is more difficult to reduce than NiO under the condition of FCC reaction.As the result,dehydrogenation activity of Ni 0 is inhibited.This is the nickel passivating mechanism of PNP.