Effect of fluoride promoter on the catalytic activity of NiWF/γ-Al2O3 for hydrodenitrogenation and hydrodesulfurization of coal tar
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摘要: 制备了一系列添加不同含量F助剂的NiWF(x)/γ-Al2O3催化剂,并采用X射线衍射(XRD)、N2吸附、X射线光电子能谱(XPS)、NH3-TPD和高分辨透射电子显微镜(HRTEM)等手段对其结构和物化性质进行了表征,同时在固定床反应器上考察了其加氢脱氮(HDN)和加氢脱硫(HDS)活性,反应原料为中国内蒙中低温煤焦油。结果显示,随着F含量的增加,催化剂孔容和孔径没有明显变化,但比表面积减小。催化剂在643 K下硫化6 h后,其硫化度随着F含量的增加而减少,强酸位数和总酸位数呈现先略微增加后减少的趋势。高分辨透射电子显微镜测试表明,硫化后的催化剂中含有具有典型层状结构的WS2。F含量对NiWF(x)/γ-Al2O3的煤焦油HDN性能有较大影响,但对其HDS活性影响很弱。
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关键词:
- 加氢脱硫 /
- 加氢脱氮 /
- F /
- NiW/γ-Al2O3 /
- 煤焦油
Abstract: A series of NiWF (x)/γ-Al2O3 catalysts were prepared by adding different amounts of ammonium fluoride, and the effects of fluoride amount on the structure and physicochemical properties were investigated with X-ray diffraction, X-ray photoelectron spectroscopy, NH3-TPD and high resolution transmission electron mcroscopy (HRTEM) techniques and N2 sorption experiment. Their hydrodenitrogenation (HDN) and hydrodesulfurization (HDS) catalytic performances were evaluated in a fix-bed reactor with low and middle-temperature coal tar obtained from Inner Mongolia as feedstock. Although fluoride amount has little effect on the pore diameter and pore volume of the catalysts, increase of the fluoride amount decreases the specific surface area. In addition, the sulfidation degree of the catalyst decreases with the fluoride amount when it is sulfided at 643 K for 6 h. Also, the numbers of strong acid sites and total amount acid sites change with increasing fluoride amount. They slightly increase at first, but then obviously decrease. HRTEM shows that WS2 slabs have a typical layered structure. The catalytic activity of NiWF (x)/γ-Al2O3 for HDN and HDS of coal tar shows a volcanic trend with the fluoride amount.-
Key words:
- hydrodesulfurization /
- hydrodenitrogenation /
- fluoride /
- NiWF/γ-Al2O3 /
- coal tar
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Figure 2 Survey scanned ((a), (b)) and deconvoluted ((c), (d)) W 4f of NiWF (x)/γ-Al2O3 ((a), (c)) and Ni 2p ((b), (d)) XPS of sulfided NiWF (0.50)/γ-Al2O3 catalysts
a: NiWF (0.00)/γ-Al2O3; b: NiWF (0.05)/γ-Al2O3; c: NiWF (0.10)/γ-Al2O3; d: NiWF (0.20)/γ-Al2O3; e: NiWF (0.50)/γ-Al2O3; f: NiWF (0.75)/γ-Al2O3; g: NiWF (1.00)/γ-Al2O3
Table 1 Pore structural parameters of NiWF (x)/γ-Al2O3 catalysts
Catalyst A/(m2·g-1) v/(cm3·g-1) d/nm NiWF (0.00)/γ-Al2O3 174.2 0.406 9.3 NiWF (0.05)/γ-Al2O3 163.2 0.399 9.8 NiWF (0.10)/γ-Al2O3 162.7 0.399 9.9 NiWF (0.20)/γ-Al2O3 162.5 0.402 9.9 NiWF (0.50)/γ-Al2O3 162.4 0.397 9.8 NiWF (0.75)/γ-Al2O3 154.2 0.397 10.3 NiWF (1.00)/γ-Al2O3 152.5 0.402 10.5 Table 2 Binding energy and sulfidation degree of W and Ni species on the catalyst surface
Catalyst NiWF (0.00) NiWF (0.05) NiWF (0.1) NiWF (0.2) NiWF (0.5) NiWF (0.75) NiWF (1.00) WS2 EB4f7/2 /eV 32.5 32.5 32.5 32.5 32.5 32.5 32.5 Relative content w/% 60.50 55.96 51.64 50.35 47.25 38.37 33.41 WO3 EB4f7/2 /eV 35.9 35.9 35.9 35.9 35.9 35.9 35.9 Relative content w/% 39.50 44.04 48.36 49.65 52.75 61.63 66.59 NiS EB2p3/2 /eV 854.2 854.2 854.2 854.2 854.2 854.2 854.2 Relative content w/% 52.89 47.31 42.38 39.34 27.49 24.52 19.37 NiO EB2p3/2 /eV 856.2 856.2 856.2 856.2 856.2 856.2 856.2 Relative content w/% 47.11 52.69 57.62 60.66 62.51 75.48 80.63 -
[1] HAN C R.Hydrocracking Technology and Engineering[M].Beijing:China Petrochemical Press, 2006:1-27. [2] LEI Z, HU D N, PAN H T, LU J Y.Research progress of coal tar catalytic hydrogenation[J].Mod Chem Ind, 2014, 34(1):30-35. https://www.researchgate.net/publication/287283354_Research_progress_of_coal_tar_catalytic_hydrogenation [3] CHEN T N, GE X J, MA J.Hydrogenation process of medium & low temperature coal tar[J].Fuel Chem Process, 2013, 44(4):52-57. http://en.cnki.com.cn/Article_en/CJFDTotal-NRHG201304027.htm [4] YU Y C, GAO H Y, ZHANG M N, QIAO S.Research progress of coal tar hydrogenation catalyst[J].Ind Prod, 2016, 42(2):137-143. https://www.researchgate.net/publication/287283354_Research_progress_of_coal_tar_catalytic_hydrogenation [5] ZHANG K Y, LIU A H, YAN J, GUO J X, LIU C G.Characterization of CoMo/Al2O3 hydrodesulfurization catalysts prepared by different methods[J].Chin J Catal, 2005, 26(8):639-644. https://www.researchgate.net/publication/237534428_Characterization_and_hydrodesulfurization_activity_of_CoMo_catalysts_supported_on_solgel_prepared_Al_2O_3 [6] ZHENG A G, FANG S L, ZHANG J, CHEN W B, XU G T.The characterization of NiMo/Al2O3 hydrotreating catalyst by TEM and AEM[J].Acta Petrol Sin, 2008, 24(4):433-437. [7] WANG Y G, ZHANG H Y, ZHANG P Z, XU D P, ZHAO K, WANG F J.Hydroprocessing of low temperature coal tar on NiW/γ-Al2O3 catalyst[J].J Fuel Chem Technol, 2012, 40(12):1492-1497. https://www.researchgate.net/publication/287293950_Hydroprocessing_of_low_temperature_coal_tar_on_NiWg-Al2O3_catalyst [8] WANG W Y, YANG Y Q, LUO H, PENG H Z, ZHANG X Z, HU T.Preparation and hydrodeoxygenation properties of Ni-Co-W-B amorphous catalyst[J].Chin J Catal, 2011, 32(10):1645-1650. https://www.researchgate.net/publication/238490136_Preparation_and_hydrodeoxygenation_properties_of_CoMoOB_amorphous_catalyst [9] WANG H Y, SONG P P, WANG Y J.Influence of hierarchically mesoporous H βzeolite on the performance of NiWP/H β-Al2O3 catalysts in diesel oil hydro-upgrading[J].J Fuel Chem Technol, 2016, 44(4):470-476. https://www.researchgate.net/publication/306178702_Influence_of_hierarchically_mesoporous_Hb_zeolite_on_the_performance_of_NiWPHb-Al2O3_catalysts_in_diesel_oil_hydro-upgrading [10] MAITY S K, LEMUS M, ANCHEYTA J.Effect of preparation methods and content of boron on hydrotreating catalytic activity[J].Energy Fuels, 2011, 25:3100-3107. doi: 10.1021/ef2004915 [11] QU L L, JIAN M, SHI Y H, LI D D.Effect of Fluorine on sulfide type NiW/γ-Al2O3 catalyst[J].Chin J Catal, 1998, 19(6):608-609. [12] JIRFITOVFI K, KRANS M.Effect of support properties on the catalytic activity of HDS catalysts[J].Appl Catal, 1986, 27(1):21-29. doi: 10.1016/S0166-9834(00)81043-X [13] MATRALIS H K, LYCOURGHIOTIS A, GRANGE P, DELMON B.Fluorinated hydrotreatment catalysts:Characterization and hydrode-sulphurization activity of fluorine-cobalt-molybdenum/γ-alumina catalysts[J].Appl Catal, 1988, 38(2):273-287. doi: 10.1016/S0166-9834(00)82831-6 [14] SARBAK Z, ANDERSSON S L T.Effect of metal-organic compounds on thiophene hydrodesulphurization over sulphided forms of fluoride-containing CoMo/Al2O3 catalysts[J].Appl Catal, 1991, 69(1):235-251. doi: 10.1016/S0166-9834(00)83305-9 [15] BENITEZ A, RAMIREZ J, FIERRO J L G, AGUDO A.Effect of fluoride on the structure and activity of NiW/Al2O3 catalysts for HDS of thiophene and HDN of pyridine[J].Appl Catal, 1996, 144(1/2):343-364. [16] LI B, SHAO L L.Appraisal of alumina and aluminium hydroxide by XRD[J].Inorg Chem Ind, 2008, 40(2):54-57. http://en.cnki.com.cn/Article_en/CJFDTOTAL-WJYG200802025.htm [17] CUI G Q, WANG J F, FAN H F, SUN X Y, JIANG Y, WANG S J, LIU D, GUI J Z.Towards understanding the microstructures and hydrocracking performance of sulfided Ni-W catalysts:Effect of metal loading[J].Fuel Process Technol, 2011, 92(12):2320-2327. doi: 10.1016/j.fuproc.2011.07.020 [18] EBRAHIMYNEJAD M, HAGHIGHI M, ASGARI N.Ultrasound assisted synthesis and physicochemical characterizations of fluorine-modified CoMo/Al2O3 nanocatalysts used for hydrodesulfurization of thiophene[J].J Nanosci Nanotechnol, 2014, 14(9):6848-6857. doi: 10.1166/jnn.2014.8966 [19] DING L H, ZHENG Y, ZHANG Z S.Hydrotreating of light cycle oil using WNi catalysts containing hydrothermally and chemically treated zeolite Y[J].Catal Today, 2007, 125(3):229-238. https://www.researchgate.net/publication/229101775_Hydrotreating_of_light_cycle_oil_using_WNi_catalysts_containing_hydrothermally_and_chemically_treated_zeolite_Y [20] NIU G X, CHEN H Y, LI Q Z.The effect of treatment of ammonium fluosilicate on NiW/γ-Al2O3[J].Chin J Catal, 1997, 18(4):279-283. [21] CORMA A, FORNES V, ORTEGA E.The nature of acid sites on fluorinated γ-Al2O3[J].Chin J Catal, 1985, 92(2):284-290. doi: 10.1016/0021-9517(85)90262-3 [22] MICIUKIEWICZ J.Studies of molybdena-alumina catalysts:XV.Effect of fluorine-modified alumina on catalyst properties[J].Appl Catal, 1989, 49(2):247-257. doi: 10.1016/S0166-9834(00)83021-3 [23] BENITEZ A, RAMIREZ J, VAZQUEZ A.Influence of alumina fluoridation on the dispersion and hydrotreating activity of W/Al2O3 catalysis[J].Appl Catal A:Gen, 1995, 133(1):103-119. doi: 10.1016/0926-860X(95)00177-8 [24] MENG X X, QIU Z G, GUO X M, LI Z R, HU N F, SONG M N, ZHAO L F.Hydrodenitrogenation and hydrodesulfurization of coal tar on Ni-W catalysts with different metal loadings[J].J Fuel Chem Technol, 2016, 44(5):570-578. https://www.researchgate.net/publication/303572786_Hydrodenitrogenation_and_hydrodesulfurization_of_coal_tar_on_Ni-W_catalysts_with_different_metal_loadings [25] EGOROVA M, PRINS R.Competitive hydrodesulfurization of 4, 6-dimethyl dibenzothiophene, hydrodenitrogenation of 2-methylpyridine and hydrogenation of naphthalene over sulfided NiMo/γ-Al2O3[J].J Catal, 2004, 224(2):278-287. doi: 10.1016/j.jcat.2004.03.005 [26] JIAN M, PRINS R.Existence of different catalytic sites in HDN catalysts[J].Catal Today, 1996, 30(1/3):127-134. http://www.ingentaconnect.com/content/els/09205861/1996/00000030/00000001/art00326