Preparation of Mg/Ce-SBA-15 catalyst and its performance on phenol alkylation with methanol
-
摘要: 以Ce-SBA-15为载体，硝酸镁为活性组分前驱体，通过浸渍法制备了Mg/Ce-SBA-15催化剂。利用XRD、N2吸附-脱附、SEM、EDS、NH3-TPD、Py-FTIR和TG-DTA手段对催化剂进行表征。结果表明，Mg掺杂并未破坏载体结构，催化剂表面弱酸含量有所增加，L酸增加明显。在固定床反应器中评价了Mg/Ce-SBA-15分子筛催化苯酚甲醇烷基化的反应性能。结果表明，Mg负载量为7%、焙烧温度为550℃、焙烧时间为4.5 h制备的Mg/Ce-SBA-15催化剂催化效果最佳。在反应温度460℃，n（苯酚）：n（甲醇）为1：4，质量空速为3.0 h-1，常压的条件下，苯酚转化率为80.1%，邻甲酚选择性为86.4%。
-
关键词:
- 介孔分子筛 /
- Mg/Ce-/SBA-15 /
- 苯酚 /
- 邻甲酚 /
- 再生性能
Abstract: Mg/Ce-SBA-15 mesoporous molecular sieves were synthesized by using Ce-SBA-15 as support and magnesium nitrate as precursor through impregnation method. The samples were characterized by XRD, N2 adsorption-desorption, BET, SEM, NH3-TPD, Py-FTIR and TG-DTA techniques. The results indicate that the original crystal structures of SBA-15 remain unchanged after modification with Mg, but the number of weak acids were increased especially L acids. The performances of catalysts in phenol alkylation with methanol were studied in a fixed bed reactor. The results showed that the catalyst showed the highest catalytic activity under the conditions of Mg content=7%, calcination temperature=550℃ and calcination time=4.5 h.At 460℃, n(phenol):n(methanol)=1:4, WHSV=3.0 h-1 and atmospheric pressure, the conversion of phenol was 80.1% and the selectivity to o-cresol was 86.4%.-
Key words:
- mesoporous molecular sieves /
- Mg/Ce-SBA-15 /
- phenol /
- o-cresol /
- regeneration
-
图 1 催化剂小角XRD谱图
Figure 1 XRD patterns of different catalysts
a: SBA-15; b: 15%Ce-SBA-15; c: 5%Mg-15%Ce-SBA-15; d: 7%Mg-15%Ce-SBA-15; e: 10%Mg/15%Ce-SBA-15
图 2 催化剂广角XRD谱图
Figure 2 XRD patterns of different catalysts
a: SBA-15; b: 15%Ce-SBA-15; c: 5%Mg-15%Ce-SBA-15; d: 7%Mg-15%Ce-SBA-15; e: 10%Mg/15%Ce-SBA-15
图 3 催化剂的扫描电镜照片
Figure 3 SEM images of different catalysts
(a): SBA-15; (b): 15%Ce-SBA-15; (c):7%Mg/15%Ce-SBA-15
图 5 催化剂的N2吸附-脱附谱图
Figure 5 adsorption-desorption isotherms of different catalysts
■: SBA-15; ○: 15%Ce-SBA-15; ▲: 5%Mg/15%Ce-SBA-15; ▽: 7%Mg/15%Ce-SBA-15; ◆: 10%Mg/15%Ce-SBA-15
图 6 催化剂的NH3-TPD谱图
Figure 6 NH3-TPD spectra of different catalysts
a: SBA-15; b: 15%Ce-SBA-15; c: 5%Mg-15%Ce-SBA-15; d: 7%Mg-15%Ce-SBA-15; e: 10%Mg/15%Ce-SBA-15
图 8 焙烧温度对烷基化性能的影响
Figure 8 Effect of calcination temperature on alkylation
a: conversion; b: selectivity
图 9 焙烧时间对烷基化性能的影响
Figure 9 Effect of calcination time on alkylation
a: conversion; b: selectivity
图 10 再生次数对催化性能的影响
Figure 10 Effect of regeneration times
: 7%Mg/15%Ce-SBA-15; : 15%Ce-SBA-15
表 1 不同催化剂的织构性质
Table 1 Textural properties of different catalysts
Catalyst ABET/
(m2·g-1)vt/
(cm3·g-1)d/nm SBA-15 942 1.13 5.6 15%Ce-SBA-15 793 0.91 5.6 5%Mg/15%Ce-SBA-15 731 0.84 5.4 7%Mg/15%Ce-SBA-15 683 0.79 5.2 10%Mg/15%Ce-SBA-15 602 0.61 4.1 
下载: 导出CSV
表 2 不同催化剂的吡啶红外酸性分析
Table 2 Py-FTIR acidity analysis results of different catalysts
Catalyst Py-FTIR acid distribution/ (μmol·g-1) 200 ℃ 350 ℃ L acid B acid L acid B acid SBA-15 0.0 0.0 0.0 0.0 15%Ce-SBA-15 54.1 135.9 77.4 259.6 3%Mg/15%Ce-SBA-15 96.4 137.6 112.6 270.5 7%Mg/15%Ce-SBA-15 131.9 140.3 154.6 287.4 10%Mg/15%Ce-SBA-15 112.4 120.3 131.4 245.6
下载: 导出CSV
表 3 不同催化剂的烷基化性能
Table 3 Alkylation activity of different catalysts
Catalyst Conversion
x/%Selectivity
s/%3%Mg/15%Ce-SBA-15 76.7 62.4 5%Mg/15%Ce-SBA-15 78.9 71.7 7%Mg/15%Ce-SBA-15 80.1 86.4 10%Mg/15%Ce-SBA-15 70.2 83.3 reaction condition: t=460 ℃; n(phenol)/n(methanol)=1:4; WHSV=3.0 h-1; m(catalyst)=1.0 g
下载: 导出CSV
表 4 不同催化剂的苯酚甲醇烷基化性能
Table 4 Alkylation performances of different catalysts
Catalyst Conversion
x/%Selectivity
s/%SBA-15 10.2 21.9 Ce-SBA-15 75.7 54.4 7%Mg/Ce-SBA-15 80.1 86.4 reaction condition: t=460 ℃; n(phenol)/n(methanol)=1:4; WHSV=3.0 h-1; m(catalyst)=1 g
下载: 导出CSV
-
[1] LIU J Y, HUANG H, ZHONG S, PENG W C, SHE X C, YIN D L. Research progress in vapor phase C-alkylation of phenol with methanol over metallic oxides[J]. Chem Ind Eng Prog, 2013, 32(11): 2609-2613. http://www.hgjz.com.cn/EN/Y2013/V32/I11/2609 [2] WANG K, XU Y, LIU Z. Cresol producing method through phenol methanol gas-phase alkylation: WO, EP2878590[P]. 2015. [3] CHARY K V R, RAMESH K, VIDYASAGAR G, RAO V V. Vapour phase alkylation of phenol with methanol over vanadium oxide supported on zirconia [J]. J Mol Catal A: Chem, 2003, 198(1/2): 195-204. http://www.ingentaconnect.com/content/els/13811169/2003/00000198/00000001/art00691 [4] GANDHE A R, FERNANDES J B. Methylation of phenol over Degussa P25 TiO2[J]. J Mol Catal A: Chem, 2005, 226(2): 171-177. doi: 10.1016/j.molcata.2004.10.035 [5] LIU Y, LOTERO E, GOODWIN J G. A comparison of the esterification of acetic acid with methanol using heterogeneous versus homogeneous acid catalysis[J]. J Catal, 2006, 242(2): 278-286. doi: 10.1016/j.jcat.2006.05.026 [6] HUANG H, ZHONG S, XU B, SHE X C. Synthesis of o-cresol from phenol and methanol via gas phase alkylation[J]. Petrochem Technol, 2010, 39(11): 1265-1268. https://www.researchgate.net/publication/289478211_Synthesis_of_o-cresol_from_phenol_and_methanol_via_gas_phase_alkylation [7] PENA L F G, SAD M E, PADRO C L, APESTEGUIA C R. Study of the alkylation of phenol with methanol on Zn (H)-exchanged NaY zeolites[J]. Catal Lett, 2011, 141(141): 939-947. https://www.researchgate.net/publication/239212473_An_investigation_into_factors_which_influence_the_formation_of_p-cresol_in_the_methanol_alkylation_of_phenol_over_MCM-22_and_ZSM-5 [8] BARMAN S, PRADHAN N C, BASU J K. Kinetics of alkylation of phenol with methanol over Ce-exchanged NaX zeolite[J]. Catal Lett, 2006, 111(1): 67-73. doi: 10.1007/s10562-006-0135-6 [9] 张悝, 项寿鹤, 张怀彬, 刘上垣, 李赫咺. HZSM-5沸石分子筛上苯酚与甲醇的烷基化反应[J].催化学报, 2001, 22(6): 545-549. http://www.cnki.com.cn/Article/CJFDTOTAL-CHUA200106010.htmZHANG Kui, XIANG Shou-he, ZHANG Huai-bin, LIU Shang-yuan, LI He-xuan. Study on methylation of phenol with methanol over HZSM-5 zeolite[J]. Chin J Catal, 2001, 22(6): 545-549. http://www.cnki.com.cn/Article/CJFDTOTAL-CHUA200106010.htm [10] SATO S, KOIZUMI K, NOZAKI F. Ortho-selective methylation of phenol catalyzed by CeO2-MgO prepared by citrate process[J]. J Catal, 1998, 178(1): 264-274. doi: 10.1006/jcat.1998.2159 [11] 史春薇, 吴文远, 边雪, 百玉婷. Y/SBA-15的微波水热法合成及其表征分析[J].东北大学学报 (自然科学版), 2015, 36(3): 397-401. http://www.cnki.com.cn/Article/CJFDTOTAL-DBDX201503021.htmSHI Chun-wei, WU Wen-yuan, BIAN Xue, BAI Yu-ting. Microwave hydrothermal synthesis and characterization of Y/SBA-15[J]. J Northeast Univ, 2015, 36(3): 397-401. http://www.cnki.com.cn/Article/CJFDTOTAL-DBDX201503021.htm [12] LASKOWSKA M, LASKOWSKI L, JELONKIEWICZ J. SBA-15 mesoporous silica activated by metal ions verification of molecular structure on the basis of Raman spectroscopy supported by numerical simulations[J]. J Mol Struct, 2015, 1100(11): 21-26. https://www.researchgate.net/publication/282223466_SBA-15_mesoporous_silica_activated_by_metal_ions_-_Verification_of_molecular_structure_on_the_basis_of_Raman_spectroscopy_supported_by_numerical_simulations [13] 任文玲, 陈绍云, 张永春, 李桂民.甲基化SBA-15分子筛的制备与表征[J].化工进展, 2011, 30(10): 2304-2309. http://www.cnki.com.cn/Article/CJFDTOTAL-HCHX201104006.htmREN Wen-ling, CHEN Shao-yun, ZHANG Yong-chun, LI Gui-min. Preparation and characterization of methylated SBA-15 molecular sieves[J]. Chem Ind Eng Prog, 2011, 30(10): 2304-2309. http://www.cnki.com.cn/Article/CJFDTOTAL-HCHX201104006.htm [14] ZHAO D, FENG J, HUO Q, MELOSH N, FREDRICKSON G, CHMELKA B, STUCKY G. Triblock copolymer syntheses of mesoporous silica with periodic 50 to 300 angstrom pores[J]. Science, 1998, 279(5350): 548-52. doi: 10.1126/science.279.5350.548 [15] 丁志杰, 郭雨, 公旭中, 陈君华. Ce-SBA-15六方介孔分子筛的合成与表征[J].硅酸盐学报, 2010, 38(2): 234-240. http://www.cnki.com.cn/Article/CJFDTOTAL-GXYB201002016.htmDING ZHi-jie, GUO Yu, GONG Xu-zhong, CHEN Jun-hua. Synthesis and characterization of Ce-SBA-15 as a hexagonal mesoporous molecular sieve[J]. J Chin Silic Soc, 2010, 38(2): 234-240. http://www.cnki.com.cn/Article/CJFDTOTAL-GXYB201002016.htm [16] 翟庆洲, 蔡建岩, 于辉, 秦亮. SBA-15分子筛的合成研究[J].硅酸盐学报, 2006, 34(3): 385-388. http://cdmd.cnki.com.cn/Article/CDMD-10165-1011152155.htmZHAI Qing-zhou, CAI Jian-yan, YU Hui, QIN Liang. Synthesis of SBA-15 molecular sieve[J]. J Chin Silic Soc, 2006, 34(3): 385-388. http://cdmd.cnki.com.cn/Article/CDMD-10165-1011152155.htm [17] ZHANG H, LI M, XIAO P, LIU D, ZOU C J. Structure and catalytic performance of Mg-SBA-15-supported nickel catalysts for CO2, reforming of methane to syngas[J]. Chem Eng Technol, 2013, 36(10): 1701-1707. https://www.researchgate.net/publication/274207557_Synthesis_characterization_and_catalytic_performance_of_MgO-coated_NiSBA-15_catalysts_for_methane_dry_reforming_to_syngas_and_hydrogen [18] ZHONG J, CHEN J, CHEN L. Selective hydrogenation of phenol and related derivatives[J]. Catal Sci Technol, 2014, 4(10): 3555-3569. doi: 10.1039/C4CY00583J [19] 赵春霞, 陈文, 刘琦, 田高. HCl对有序介孔氧化硅结构与形貌的影响[J].物理化学学报, 2006, 22(10): 1201-1205. doi: 10.3866/PKU.WHXB20061006ZHAO Chun-lei, CHEN Wen, LIU Qi, TIAN Gao. Influence of HCl on the mesostructure and morphology of the ordered mesoporous silica[J]. Acta Phys Chim Sin, 2006, 22(10): 1201-1205. doi: 10.3866/PKU.WHXB20061006 [20] POLICE A K R, BASAVARAJU S, VALLURI D, MACHIRAJU S. Photocatalytic activity of Ce-modified SBA-15 for the degradation of isoproturon[J]. Bull Mater Sci, 2015, 38(1): 227-234. doi: 10.1007/s12034-015-0840-0 [21] LUAN Z H, HARTMANN M, ZHAO D Y, ZHOU W Z. Alumination and ion exchange of mesoporous SBA-15 molecular sieves[J]. Chem Mater, 1999, 11(6): 1621-1627. doi: 10.1021/cm9900756 [22] 史春薇, 王鑫, 郭秀东, 赵杉林, 李剑虹. Ce-SBA-15改性分子筛催化氧化油酸的研究[J].硅酸盐通报, 2014, 33(7): 1748-1751. http://www.cnki.com.cn/Article/CJFDTOTAL-GSYT201407041.htmSHI Chun-wei, WANG Xin, GUO Xiu-dong, ZHAO Shan-lin, LI Jian-hong. Study on catalytic oxidation of oleic acid by Ce-SBA-15 modified molecular sieve[J]. Bull Chin Ceram Soc, 2014, 33(7): 1748-1751. http://www.cnki.com.cn/Article/CJFDTOTAL-GSYT201407041.htm [23] 阮本玺, 沈健, 李少凯, 聂宁.铌改性SBA-15催化氧化FCC汽油脱硫[J].辽宁石油化工大学学报, 2013, 33(3): 24-27. http://www.cnki.com.cn/Article/CJFDTOTAL-FSSX201303007.htmRUAN Ben-xi, SHEN Jian, LI Shao-kai, NIE Ning. Catalytic oxidative desulfurization from FCC gasoline by niobium modified SBA-15[J]. J Liaoning Univ Petrochem Technol, 2013, 33(3): 24-27. http://www.cnki.com.cn/Article/CJFDTOTAL-FSSX201303007.htm [24] WANG Y L, SONG Y Y, HUO W T, JIA M J, JING X Y, YANG P P, YANG Y, LIU G, ZHANG, W X. Vapor phase ortho-selective alkylation of phenol with methanol over silica-manganese mixed oxide catalysts[J]. Chem Eng J, 2012, s 181-182(2): 630-635. doi: 10.3866/PKU.WHXB20090208 [25] ACEBEDO M D, BEDOGNI G A, OKULIK N B, PADRO C L. Study of gas phase m-cresol alkylation with methanol on solid acid catalysts[J]. Catal Lett, 2014, 144(11): 1946-1954. doi: 10.1007/s10562-014-1358-6 [26] 王俊丰, 沈健, 任铁强. Ce-SBA-15的制备及其苯酚甲醇烷基化性能[J].分子催化, 2016, 30(6): 523-531. http://www.cnki.com.cn/Article/CJFDTOTAL-FZCH201606006.htmWANG Jun-feng, SHEN Jian, REN Tie-qiang. Preparation of Ce-SBA-15 catalyst and its performance on phenol alkylation with methanol[J]. J Mol Catal, 2016, 30(6): 523-531. http://www.cnki.com.cn/Article/CJFDTOTAL-FZCH201606006.htm [27] WANG N, CHU W, ZHANG T, ZHAO X S. Synthesis, characterization and catalytic performances of Ce-SBA-15 supported nickel catalysts for methane dry reforming to hydrogen and syngas[J]. Fuel Energy Abs, 2012, 37(1): 19-30. https://www.researchgate.net/profile/Wei_Chu5/publication/251580269_Synthesis_characterization_and_catalytic_performances_of_Ce-SBA-15_supported_nickel_catalysts_for_methane_dry_reforming_to_hydrogen_and_syngas/links/566d72ec08ae430ab4fff212.pdf?origin=publication_list [28] SAHU D R, HONG L Y, WANG S C, HUANG J L. Synthesis, analysis and characterization of ordered mesoporous TiO2 /SBA-15 matrix: Effect of calcination temperature[J]. Microporous Mesoporous Mater, 2009, 117(3): 640-649. doi: 10.1016/j.micromeso.2008.08.013 -
点击查看大图
计量
- 文章访问数: 103
- HTML全文浏览量: 52
- PDF下载量: 5
- 被引次数: 0
