Yuan Chengyuan, Zhou Lei, Chen Qiang, Su Chengzhuang, Li Zhongfu, Ju Guannan
School of Materials Science and Engineering, Shandong University of Technology, Zibo 255000, China.
Shanxi Tengmao Technology Co., Ltd., Hejin 043300, China.
Materials (Basel). 2022 Oct 17;15(20):7220. doi: 10.3390/ma15207220.
Fluid catalytic cracking (FCC) is still a key process in the modern refining area, in which nickel-contamination for an FCC catalyst could obviously increase the dry gas and coke yields and thus seriously affect the stability of the FCC unit. From the points of surface acidity modification and Ni-passivation, in this paper, a boron-modified FCC catalyst (BM-Cat) was prepared using the in situ addition method with BO as a boron source and emphatically investigated its mechanism and performance of anti-nickel contamination. The mechanism research results suggested that, in calcination, boron could destroy the structure of the Y zeolite and thus decrease the total acid sites and strong acid sites of the Y zeolite from 291.5 and 44.6 μmol·g to 244.2 and 32.1 μmol·g, respectively, which could obviously improve the dry gas and coke selectivity of the catalyst and thus enhance the nickel capacity for BM-Cat; on the other hand, under hydrothermal conditions, boron could react with NiO and form into NiBO, which could obviously raise the range of the reduction temperature for NiO from 350-600 °C to 650-800 °C and thus promote the nickel-passivation ability for BM-Cat. Therefore, evaluation results of heavy oil catalytic cracking indicated that, under the same nickel-contamination condition, in contrast to the compared catalyst (C-Cat), the dry gas yield, coke yield, and H/CH of BM-Cat obviously decreased by 0.77 percentage points, 2.09 percentage points, and 13.53%, respectively, with light yield and total liquid yield increasing by 3.25 and 2.08 percentage points, respectively, which fully demonstrates the excellent anti-nickel contamination performance of BM-Cat.
流化催化裂化（FCC）仍是现代炼油领域的关键工艺，其中FCC催化剂的镍污染会显著增加干气和焦炭产率，从而严重影响FCC装置的稳定性。本文从表面酸性改性和镍钝化的角度出发，采用原位添加法，以硼酸为硼源制备了硼改性FCC催化剂（BM-Cat），并着重研究了其抗镍污染的机理和性能。机理研究结果表明，在煅烧过程中，硼会破坏Y型沸石的结构，从而使Y型沸石的总酸位和强酸位分别从291.5和44.6 μmol·g降至244.2和32.1 μmol·g，这可显著提高催化剂的干气和焦炭选择性，从而增强BM-Cat对镍的容纳能力；另一方面，在水热条件下，硼会与NiO反应生成NiBO，这可明显将NiO的还原温度范围从350-600 °C提高到650-800 °C，从而提高BM-Cat的镍钝化能力。因此，重油催化裂化的评价结果表明，在相同的镍污染条件下，与对比催化剂（C-Cat）相比，BM-Cat的干气产率、焦炭产率和H/CH分别明显降低了0.77个百分点、2.09个百分点和13.53%，轻质油产率和总液体产率分别提高了3.25和2.08个百分点，这充分证明了BM-Cat具有优异的抗镍污染性能。
