摘要
对DFP型无毒钝化剂的轻油微反评价和工业中试都显示 ,在FCC过程中适量使用 ,可有效提高轻油收率 ,降低氢气和焦炭产率 ,钝镍效果明显。结合TPR ,TPD ,XRD和量子化学计算的研究结果表明 ,DFP的钝镍活性组分在FCC再生条件下 (约 70 0℃ ,氧化性气氛 )分解生成氧化镁 ,进而和氧化镍在 (2 2 0 )晶面发生晶格取代 ,增加了Ni2 + 的能量最低空轨道 (LUMO)能量 ,降低了高价镍在FCC反应条件 (约 5 0 0℃ ,还原性气氛 )下的还原度 ,抑制了FCC催化剂上低价镍的强脱氢活性 。
The excellent effectiveness of nickel passivation has been demonstrated by the industrial application of a new type of nickel passivator named DFP.In this paper,the methods of MAT,TPR and XRD were used,combined with quantum chemistry calculation.The results show that lattice substitution takes place between MgO and NiO after the addition of DFP to Ni-deposited zeolite,which leads to the energy of LUMO increasing in Ni 2+ and then lowers the reducibility of Ni 2+ under the condition of FCC reaction. Therefore,the dehydrogenation activity of Ni 0 is inhibited. This is the mechanism of nickel passivation by DFP.
出处
《石油与天然气化工》
CAS
CSCD
北大核心
2001年第4期187-188,201,共3页
Chemical engineering of oil & gas
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 1 98号 )
