不同硅铝比ZSM-5分子筛的合成及其性能研究

doi:10.3969/j.issn.1001-1803.2021.01.008

Abstract

Abstract:

Five kinds of ZSM-5 with SiO₂/Al₂O₃ratios of 100, 110, 120, 160 and 200 were synthesized using the low-cost tetraethlammonium bromide （TEABr） as surfactant, sodium silicate and aluminium sulfateunder as raw materials under hydrothermal condition in a 2 L high pressure magnetic stirred reactor, and were prepared as catalysts. The samples were characterized by XRD, SEM and NH₃-TPD. The results showed that with the increase of SiO₂/Al₂O₃ratio, the SiO₂/Al₂O₃ ratio and the average particle size of the product increase, the number of the total pores and micropores decreases, the number of mesoporous increases at first then decreases, and the strong and weak acidity decrease gradually. The ethylbenzene dealkylation/xylene isomerization reaction was carried out over these samples to evaluate the catalytic performance under the following conditions: temperature of 370 ℃, hydrogen pressure of 0.8 MPa, mass space velocity of 8 h^-1 and hydrogen-hydrocarbon molar ratio of 2.0. It was found that with the increase of SiO₂/Al₂O₃ratio, the conversion of ethylbenzene decreases, and the isomerization activity of xylene increases at first then decreases. The corresponding sample with SiO₂/Al₂O₃ ratio of 120 has the optimum comprehensive performance, the conversion of ethylbenzene is 57.60%, and the isomerization activity of xylene reaches the thermodynamic equilibrium value of 24.04%.

Key words: ZSM-5 zeolite, SiO₂/Al₂O₃ ratio, ethylbenzene dealkylation, xylene isomerization

CLC Number:

TQ423

SONG Kai-yun,LI Guo-dong,LI Ning,LIANG Ya-ning,LI Xiao-feng,DOU Tao. Research on the synthesis and performance of ZSM-5 zeolite withdifferent SiO₂/Al₂O₃ ratios[J].China Surfactant Detergent & Cosmetics, 2021, 51(1): 44-49.

Figures/Tables 8

Fig. 1

Tab. 1

Fig. 2

Fig. 3

Tab. 2

Fig. 4

Tab. 3

Fig. 5

References 15

[1]	Ren Liyan. The caluculation for the production process of para-xylene with an annual output of 0.5 million tons[D]. Jinan: Shandong University, 2015.
[2]	Tang Xiaoping, Tu Qinghua, Wang ziyao, et al. Analysis on the competitivenes of paraxylene industry in China[J]. Chemical Industry, 2016,34(6) : 16-20.
[3]	Kuzmanich G B, Moscoso J G, Jan D Y. High meso-surface area and high acid site density pentasil zeolite for use in xylene conversion: US9890094[P]. 2018-02-13.
[4]	Liu Zhongxun, Zhang Rong, Yin Xiao, et al. Commercial application of SKI-110 catalyst for C8 aromatics isomerization[J]. Petroleum Processing and Petrochemicals, 2011,42(2) : 38-41.
[5]	Zhao Kui, Cai Yiliang, Liu Hongxin. Commercial application of I-350 catalyst for C8 aromatics isomerization[J]. Petroleum Refinery Engineering, 2014,44(11) : 37-40.
[6]	Liu Zhongxun, Zhou Zhenhuan, Zhao Bin, et al. The development and industrial application of deethylating type C8 aromatics isomerization catalyst[C]// Conference proceedings of the 5th Beijing technical progress in refining and petrochemical industry exchange meeting. Beijing: Beijing Petrochemical Press, 2011: 276-286.
[7]	Liu Zhongxun, Ruan Chi, Gu Haohui, et al. Influence of steam treating on deethylating type isomerization catalyst[J]. China Petroleum Processing and Petrochemical Technology, 2005 (2) : 53-62.
[8]	Fernandez C, Stan I, Gilson J P, et al. Hierarchical ZSM-5 zeolites in shape-selective xylene isomerization: role of mesoporosity and acid site speciation[J]. Chemistry-A European Journal, 2010,16(21) : 6224-6233.
[9]	Zhou Zhenhuan, Zhang Aijun, Hu Weijun, et al. Acidity of molecular sieve for C8 aromatic isomerization and reaction mechanism analysis[J]. Petroleum Refining and Petrochemicals, 2017,48(11) : 76-81.
[10]	Treacy M M J, Higgins J B. Collection of simulated XRD powder patterns for zeolites [M]. London: The International Zeolite Association Press, 2007: 276-277.
[11]	Zhou Zhenhuan, Kang Chenglin, Zhang Aijun, et al. Study on xylene isomerization mechanisms and catalyst improvement[J] . Petroleum Processing and Petrochemicals, 2017,48(9) : 7-13.
[12]	Neimark A V, Sing K S W, Thommes M. Surface area and porosity [M]. Berlin: Wiley-VCH Verlag GmbH and Co. KGaA Press, 2008: 721-737.
[13]	Bu L, Nimlos M R, Robichaud D J, et al. Diffusion of aromatic hydrocarbons in hierarchical mesoporous H-ZSM-5 zeolite[J]. Catalysis Today, 2018,312(15) : 73-81.
[14]	Zhou Jian, Liu Zhicheng, Li Liyuan, et al. Hierarchical mesoporous ZSM-5 zeolite with increased external surface acid sites and high catalytic performance in o-xylene isomerization[J]. Chinese Journal of Catalysis, 2013,34(7) : 1429-1433.
[15]	Zhang Yanxia, Guo Hongchen, Yuan Shenghua, et al. Study on the synthesis conditions of small crystal ZSM-5 Zeolite Molecular Sieves[C]// Conference proceedings of the 11th national youth congress on catalysis. Qingdao: China University of Petroleum Press, 2007: 150-151.

样品	产物硅铝比	相对结晶度/%
S-100	42.88	110.53
S-110	44.51	110.75
S-120	46.22	108.79
S-160	57.14	110.01
S-200	65.18	108.37

样品	S_BET/（m²·g^-1）	S_mic/（m²·g^-1）	S_ex/（m²·g^-1）	V_tota/（cm³·g^-1）	V_mic/（cm³·g^-1）	V_meso/（cm³·g^-1）
S-100	412.21	370.21	42.00	0.16	0.15	0.01
S-110	402.87	357.06	45.81	0.18	0.14	0.04
S-120	376.25	292.52	83.73	0.19	0.12	0.07
S-160	361.76	282.39	79.37	0.17	0.11	0.06
S-200	329.68	264.56	65.12	0.15	0.10	0.05

样品	弱酸		强酸		总量/（mmol·g^-1）
样品	温度/℃	数量/（mmol·g^-1）	温度/℃	数量/（mmol·g^-1）	总量/（mmol·g^-1）
S-100	231	1.04	451	0.70	1.74
S-110	240	1.03	454	0.66	1.69
S-120	240	0.96	440	0.65	1.61
S-160	232	0.91	451	0.39	1.30
S-200	243	0.87	452	0.36	1.23

Research on the synthesis and performance of ZSM-5 zeolite withdifferent SiO₂/Al₂O₃ ratios

RichHTML

PDF (PC)

Like

Knowledge

Abstract

Cite this article

share this article

Figures/Tables 8

References 15

Related Articles 3

Metrics

Comments

Recommended 10

[1]	GAO Li-xia, LI Xiao-feng, GAO Meng, LIU Xiao-zhen, LI Guo-dong, DOU Tao. Synthesis of EU-1 zeolites with special morphology using double-headed quaternary ammonium salt and their catalytic performance [J]. China Surfactant Detergent & Cosmetics, 2017, 47(7): 379-383.
[2]	LI Xiao-feng,SUN Xiao-tao,ZHANG Yan-ting,LIU Xiao-zhen,REN Peng-chao,DOU Tao. Preparation of mesoporous zeolite EU-1 with assistance of surfactants [J]. China Surfactant Detergent & Cosmetics, 2016, 46(10): 580-584.
[3]	ZHANG Yan-ting, LI Xiao-feng, JIA Miao-juan, JING Chao, SUN Xiao-tao, DOU Tao. Synthesis of EU-1 zeolite without use of sodium hydroxide and its catalytic performance [J]. China Surfactant Detergent & Cosmetics, 2014, 44(7): 387-389.

Research on the synthesis and performance of ZSM-5 zeolite withdifferent SiO2/Al2O3 ratios

RichHTML

PDF (PC)

Like

Knowledge

Abstract

Cite this article

share this article

Figures/Tables 8

References 15

Related Articles 3

Metrics

Comments

Recommended 10

Research on the synthesis and performance of ZSM-5 zeolite withdifferent SiO₂/Al₂O₃ ratios