摘要
磷酸盐无毒钝镍剂可有效钝化催化裂化催化剂上沉积镍对催化剂的污染 ,该剂的整体钝镍性能不低于目前应用广泛的锑基有毒钝镍剂YXM。结合MAT、TPR、XRD等实验方法和量子化学计算理论研究阐明了该钝镍剂的钝镍机理 :在FCC再生条件 (约 70 0℃ ,氧化性气氛 )下 ,由于磷基钝镍剂热分解生成P2 O5并与NiO反应生成NiP4 O1 1 ,增加了Ni2 + 的LUMO能量 ,降低了Ni2 + 在FCC反应条件 (约 5 0 0℃ ,还原性气氛 )下的还原度 ,抑制了Ni0 的强催化脱氢活性 ,从而降低催化裂化过程的H2 和焦炭产率 ,提高汽油收率 。
The non-toxic nickel passivator(named PPN) consisting of phosphates can decrease the yields of hydrogen and coke by 35% and 10% respectively,while increasing the yield of gasoline by 1%.This passivating effective is superior than that of the toxic Sb-contained nickel passivator(YXM).The passivating mechanism of PPN has also been investigated by means of MAT,TPR,TPD,XRD and quantum chemistry methods.The results show that under the condition of FCC regeneration(～700 ℃,oxidizing atmosphere),PPN decomposes to form P 2O 5 which reacts with NiO to from the new phase NiP 4O 11 .Because the energy of LUMO of Ni 2+ in NiP 4O 11 is much higher than that of Ni 2+ in NiO,NiP 4O 11 is more difficult to be reduced than NiO under the condition of FCC reaction(～500 ℃,reducing atmosphere).Therefore,the catalytic dehydrogenation activity of Ni 0 is inhibited.
出处
《无机盐工业》
CAS
2001年第6期14-16,共3页
Inorganic Chemicals Industry
基金
中国石油天然气集团公司"九五"科技攻关项目 ((96)科字第 198号 )
