高氮原料重整预加氢催化剂的制备及其性能

Preparation and properties of high nitrogen feed reforming pre-hydrogenation catalyst

采用钛和硅对氧化铝载体进行改性,通过优化Co-Mo-Ni-W四种活性组分及采用络合浸渍免高温焙烧技术,制备了适用于高氮原料的重整预加氢催化剂。采用Py-FTIR,XRD,BET,XRF,SEM,EDS等方法对催化剂进行表征,并在200 mL中试加氢装置上评价了催化剂的性能。表征结果显示,改性后载体的L酸量提高,并产生了少量B酸中心;Co-Mo-Ni-W四组分在载体表面实现了高度分散;催化剂的比表面积与孔体积均较高,分别达到了215.6 m^2/g及0.31 mL/g,有利于加氢处理高氮原料,提高了催化剂耐积碳及长周期稳定运转性能。实验结果表明,在氢分压2.0 MPa、液态空速2.0 h^-1、氢油体积比150、反应温度不低于275℃的条件下,催化剂能够将氮含量不大于20μg/g的重整预加氢原料中的氮化物脱除至含量小于0.5μg/g,符合催化重整进料要求;在1500 h长周期稳定性考察中,催化剂的温升为0.002℃/h。

Alumina carrier was modified by titanium and silicon.By optimizing the Co-Mo-Ni-W four active metals and combining with the preparation technology of low-temperature non-calcination with complex impregnation,the catalyst for reforming pre-hydrogenation of high nitrogen feedstock was prepared.The catalyst was characterized by Py-FTIR,XRD,BET,XRF,SEM,EDS,and its hydrogenation properties were studied by a 200 mL pilot hydrogenation evaluation unit.The result showed that the L acid content of the modified carrier increased and produced a little B acid compared with the alumina.The four active components of CO-Mo-Ni-W were highly dispersed on the surface of the carrier.The specific surface area and pore volume of the catalyst were both large,respectively 215.6 m^2/g and 0.31 mL/g.The reasonable acid content,high specific surface area,and pore volume and other characteristics of the catalyst can improve the hydrogenation activity,anti-carbon deposition,and long-term stable operation performance of the catalyst in the treatment of high nitrogen feedstock.Under the process conditions of hydrogen partial pressure 2.0 MPa,LHSV 2.0 h-1,the volume ratio of hydrogen to oil 150,reaction temperature not less than 275℃,the catalyst was able to hydrotreat the feedstock with nitrogen content less than 20μg/g and meet the feeding requirements of the catalytic reforming unit.The 1500 h long cycle stability study showed that the temperature rise of the catalyst was 0.002℃/h.