柠檬酸复合改性对多环芳烃选择性开环铂/Beta催化剂性能的影响
收稿日期: 2020-12-15
网络出版日期: 2021-07-08
基金资助
中国海油石油总公司项目(CNOOC-KJ-135 FZDXM 00 TJY 005-2016)
Effect of citric acid assisted hydrothermal dealumination on performance of Pt/Beta catalysts for selective ring opening of polycyclic aromatic hydrocarbons
Received date: 2020-12-15
Online published: 2021-07-08
通过水热处理、柠檬酸处理及其复合处理对Beta分子筛进行后改性,并以改性后的载体制得铂/Beta催化剂。采用X射线衍射（XRD）、X射线荧光光谱仪（XRF）、程序升温脱附（NH3-TPD）、红外吡啶吸附（Py-IR）、骨架铝核磁共振技术（27Al MAS NMR）及骨架硅核磁共振技术（29Si MAS NMR）等表征了改性前后Beta分子筛的物化性质,并考察了改性前后铂/Beta的多环芳烃选择性开环性能。结果表明,Beta分子筛在柠檬酸处理过程中可同时发生络合脱铝与骨架补铝,实现骨架铝的再分布;Beta分子筛在水热处理过程中优先脱除稳定性相对较低的Si（2 Al）处骨架铝,产生骨架缺陷的同时生成一定比例的二次介孔结构;水热-柠檬酸复合处理影响Beta分子筛骨架补铝及骨架铝再分布的效果,水热处理后Beta分子筛中存在更多的骨架缺陷,促进活性Al（OH）2+物种的骨架补铝作用。当Beta分子筛采用水热-柠檬酸复合处理顺序时,骨架补铝及骨架铝再分布效果显著,样品以中强酸为主,且具有较高的B酸量与L酸量的比值,所制备催化剂的多环芳烃选择性开环活性及稳定性最优。
臧甲忠 , 马明超 , 于海斌 , 范景新 , 郭春垒 , 靳凤英 . 柠檬酸复合改性对多环芳烃选择性开环铂/Beta催化剂性能的影响[J]. 无机盐工业, 2021 , 53(6) : 205 -211 . DOI: 10.19964/j.issn.1006-4990.2020-0647
Beta zeolites were post modified by hydrothermal treatment,citric acid treatment and duplex treatment,and the Pt/beta catalyst was prepared with the modified support.The physicochemical properties of the the modified and unmodified beta zeolites were characterized by X-ray diffraction（XRD）,X-ray fluorescence spectrometry（XRF）,temperature programmed desorption（NH3-TPD）,infrared pyridine adsorption（Py-IR）,framework aluminum nuclear magnetic resonance（27Al MAS NMR） and framework silicon nuclear magnetic resonance（29Si MAS NMR）,and the performance of the modified and unmod-ified Pt/beta on selective ring opening of polycyclic aromatic were investigated.The results showed that dealumination and re-alumination of Beta zeolite performed in citric acid treatment,leading to framework Al redistribution.In the process of hydro-thermal treatment,beta zeolite preferentially removed the framework aluminum at Si（2Al）,which had relatively low stability,and produced framework defects and a certain proportion of secondary mesoporous structure.The hydrothermal-citric acid du-plex treatment made a difference to framework aluminum addition and redistribution of beta zeolite.After hydrothermal treat-ment,there were more framework defects in beta molecular sieves,which could promote the framework supplement of active Al（OH）2+ species.When the hydrothermal-citric acid duplex treatment sequence was used for beta zeolite,the effect of frame-work aluminum supplement and framework aluminum redistribution was significant.The sample was mainly medium strong acid with a high ratio of B acid content to L acid content.The as-prepared catalyst had the best selective ring opening activity and stability for polycyclic aromatic hydrocarbons.
| [1] | 谢朝钢, 叶岗. 市场导向炼油企业转型升级的技术选择[J]. 石油炼制与化工, 2019,50(4):1-6. |
| [2] | 辛靖, 高杨, 侯章贵, 等. 以生产轻芳烃为目的的催化重整装置原料拓展研究进展[J]. 无机盐工业, 2019,51(7):1-7. |
| [3] | Lee J, Choi Y, Shin J, et al. Selective hydrocracking of tetralin for light aromatic hydrocarbons[J]. Catalysis Today, 2016,265:144-153. |
| [4] | Kenmogne R, Finiels A, Cammarano C, et al. Hydroconversion of nhexadecane over bifunctional microporous and mesoporous model catalysts influence of pore architecture on selectivity[J]. Journal of Catalysis, 2015,329:348-354. |
| [5] | Kubicka D, Kumar N, Mäki-Arvela P, et al. Ring opening of decalin over zeolites:Ⅱ.activity and selectivity of platinum-modified zeolit-es[J]. Journal of Catalysis, 2004,227:313-327. |
| [6] | Santikunaporn M, Herrera J E, Jongpatiwut S, et al. Ring opening of decalin and tetralin on HY and Pt/HY zeolite catalysts[J]. Journal of Catalysis, 2004,228:100-113. |
| [7] | 陈妍, 宋海涛, 朱玉霞, 等. Beta和Y型分子筛催化四氢萘裂化规律的对比[J]. 石油学报:石油加工, 2015,31(3):650-656. |
| [8] | Wei B, Jin L, Wang D, et al. Effect of different acid-leached USY zeolites on In-Situ catalytic upgrading of lignite tar[J]. Fuel, 2020,266:117089-117099. |
| [9] | Hajjar R, Millot Y, Man P P, et al. Two kinds of framework Al sites studied in BEA zeolite by X-ray diffraction,fourier transform in-frared spectroscopy,NMR techniques,and V Probe[J]. The Journal of Physical Chemistry C, 2008,112:20167-20175. |
| [10] | Wang W, Zhang W, Chen Y, et al. Mild-acid-assisted thermal or hy-drothermal dealumination of zeolite Beta,its regulation to Al dist-ribution and catalytic cracking performance to hydrocarbons[J]. Journal of Catalysis, 2018,362:94-105. |
| [11] | Apelian M R, Fung A S, Kennedy G J, et al. Dealumination of zeo-lite β via dicarboxylic acid treatment[J]. The Journal of Physical Chemistry, 1996,100:16577-16583. |
| [12] | Mihályi R M, Kollár M, Király P, et al. Effect of extra-framework Al formed by successive steaming and acid leaching of zeolite MCM-22 on its structure and catalytic performance[J]. Applied Catalysis A:General, 2012,417-418:76-86. |
| [13] | Huang L, Wang P, Li J, et al. Effect of acid leaching and catalytic properties of zeolite MWW utilized as ehene methylation cataly-st[J]. Microporous and Mesoporous Materials, 2016,223:230-240. |
| [14] | 王成强, 欧阳颖, 罗一斌. 有机酸脱铝对β分子筛环烷烃开环反应性能的影响[J]. 石油炼制与化工, 2015,46:30-35. |
| [15] | Xie Z, Chen Q, Zhang C, et al. Influence of citric acid treatment on the surface acid properties of zeolite Beta[J]. The Journal of Physical Chemistry B, 2000,104:2853-2859. |
| [16] | Maache M, Janin A, Lavalley J C, et al. Acidity of zeolites beta de-aluminated by acid leaching:an FTIR.study using different probe molecules(pyridine,carbon monoxide)[J]. Zeolites, 1993,13:419-426. |
| [17] | Baran R, Millot Y, Onfroy T, et al. Influence of the nitric acid treat-ment on Al removal,framework composition and acidity of BEA zeolite investigated by XRD,FTIR and NMR[J]. Microporous and Mesoporous Materials, 2012,163:122-130. |
| [18] | Dzwigaj S, Millot Y, Krafft J M, et al. Incorporation of silver atoms into the vacant T-atom sites of the framework of Si-BEA zeolite as mononuclear Ag(I) evidenced by XRD,FTIR,NMR,DR UV-vis,XPS,and TPR[J]. The Journal of Physical Chemistry C, 2013,117:12552-12559. |
| [19] | Jin Y, Xiao C, Liu J, et al. Mesopore modification of beta zeolites by sequential alkali and acidtreatments:narrowing mesopore size distribution featuring unimodality and mesoporous texture proper-ties estimated upon a mesoporous volumetric model[J]. Microporo-us and Mesoporous Materials, 2015,218:180-191. |
| [20] | Caillot M, Chaumonnot A, Digne M, et al. The variety of Brϕnsted acid sites in amorphous aluminosilicates and zeolites[J]. Journal of Catalysis, 2014,316:47-56. |
| [21] | 鞠雪艳, 胡志海, 蒋东红, 等. 金属与分子筛含量对预加氢1-甲基萘的加氢裂化催化剂的影响[J]. 石油学报:石油加工, 2012,28:711-716. |
| [22] | Zecevic J, Vanbutsele G, de Jong K P, et al. Nanoscale intimacy in bifunctional catalysts for selective conversion of hydrocarbons[J]. Nature, 2015,528:245-248. |
| [23] | Im J, Shin H, Jang H, et al. Maximizing the catalytic function of hy-drogen spillover in platinum-encapsulated aluminosilicates with controlled nanostructures[J]. Nature Communications, 2014,5. Doi: 10.1038/ncomms4370. |
| [24] | Guisnet M. “Ideal” bifunctional catalysis over Pt-acid zeolites[J]. Catalysis Today, 2013,218:123-134. |
/
| 〈 |
|
〉 |
