Effect of pore structure and acidic property of MCM-22 zeolite on product distribution of benzene alkylation with propylene
Li, YX; Chen, BH; Meng, WJ; Li, CY; Wang, WX; Cao, G
| HERO ID | 3576555 |
|---|---|
| In Press | No |
| Year | 2003 |
| Title | Effect of pore structure and acidic property of MCM-22 zeolite on product distribution of benzene alkylation with propylene |
| Authors | Li, YX; Chen, BH; Meng, WJ; Li, CY; Wang, WX; Cao, G |
| Journal | Cuihua Xuebao / Chinese Journal of Catalysis |
| Volume | 24 |
| Issue | 7 |
| Page Numbers | 494-498 |
| Abstract | MCM-22, having MWW topology, Is a zeolite which has unique and unusual pore structure and acidic property on its external surface. In this paper, the total acid sites of MCM-22 (n(Si)/n(Al) = 15) were measured by means of TG and FT-IR. The B and L acid sites were 375 and 450 mumol/g respectively, and the external surface acid sites were 45 mumol/g. The ratio of initial reaction rate of benzene alkylation over beta zeolite ( n (Si) /n (Al) = 15) to that over MCM-22 was better consistent with the ratio of B acid sites on beta zeolite to that on the MCM-22 external surface. It was showed that the benzene alkylation took place on the external surface of MCM-22 and in the 12 MR pore channels of beta zeolite, respectively. The distribution of products, including isopropyl benzene(IPB), diisopropyl benzene(DIPB), tri-isopropyl benzene(TIPB), oligomers(Olig) and n-propyl benzene(NPB), was studied under the conditions of n(C6H6)/n(C3H6) = 2similar to10, WHSV(C3H6) = 2.5similar to30 h(-1), p = 3.0 MPa and theta = 140similar to210 degreesC. On the basis of the diffusion coefficients of the reactants and the energy barriers of the products in MCM-22 and beta zeolites, it was found that: (1) owing to that the benzene alkylation took place on the MCM-22 external surface, the selectivity for IPB was lower by 2%similar to4%, and the amount of DIPB and TIPB was higher over MCM-22 than over beta zeolite; (2) the B acid sites located in the 10 MR sinusoidal channels of MCM-22 may not take part in the benzene alkylation owing to the steric effect, but it may take part in oligomerization of propylene, so the oligomers formed over MCM-22 were higher than those over beta zeolite;. |
| Wosid | WOS:000184850800005 |
| Url | https://www.scopus.com/inward/record.uri?eid=2-s2.0-33750498512&partnerID=40&md5=55a1e9d64599f52c9068ba4e045ef72d |
| Is Certified Translation | No |
| Dupe Override | No |
| Is Public | Yes |
| Language Text | English |
| Keyword | MCM-22 zeolite; beta zeolite; benzene; propylene; alkylation |