两类典型渣油原料加氢过程中脱金属催化剂运转初期失活研究

Study on the Initial Deactivation of Hydrodemetallization Catalyst in Hydrotreating Process With Two Kinds of Typical Residue Feedstocks

采用碳硫元素分析(CS)、催化剂氮含量分析(CAT-N)、热重-质谱联用分析(TG-MS)以及低温静态N2物理吸附等技术手段,分别对在中型固定床渣油加氢实验装置上运转0(硫化后)、162、262、562h后的卸出加氢脱金属催化剂进行表征,以研究高氮低硫类渣油加氢过程运转初期催化剂失活快的原因。结果表明:在相同催化剂级配体系和相同工艺条件下,与加工高硫低氮类沙特阿拉伯轻质原油的渣油原料(沙轻渣油)的脱金属催化剂相比,加工高氮低硫类仪长管输原油的渣油原料(仪长渣油)的脱金属催化剂上形成了更多的积炭,沉积的硫化物略少,而氮化物较多;加工仪长渣油的脱金属催化剂上形成了更多的高温型积炭,且相比加工沙轻渣油的脱金属催化剂上形成的高温型积炭更难氧化燃烧;积炭对加工仪长渣油的脱金属催化剂的孔结构性质影响更大,比表面积、孔体积均低于加工沙轻渣油的脱金属催化剂,大孔占比更低。

The properties and deactivation behavior of the discharged hydrodemetallization (HDM) catalysts,which was used for 0,162,262 and 562 h in the fixed bed residue hydrotreating pilot unit with Yichang atmospheric residue (Yichang AR) and Saudi Arabian atmospheric residue (Saudi Arabian AR) as feedstocks,were characterized by elemental analysis of carbon and sulfur (CS),catalyst elemental analysis of nitrogen (CAT-N),thermogravimetric mass spectrometry analysis (TG-MS),and low temperature N 2 physical adsorption.Results show that more coke,less sulfur compound and more nitrogen compound deposited were formed for Yichang AR than those of Saudi Arabian AR,under the same grading HDM catalysts system and the same process conditions.In addition,more high-temperature type coke is formed on the HDM catalyst for Yichang AR,which is more difficult to be oxidized by combustion in air,with lower specific surface area and pore volume remained.