Adsorption equilibrium of xylene isomers and ethylbenzene on MIL-125(Ti)_NH2: the temperature influence on the para-selectivity

• Type: Article in International Scientific Journal
• Date: 2018

Authors

Mariana A. Moreira (Author) FEUP; Mónica P. S. Santos (Author) Other; Cláudia G. Silva (Author) FEUP; José M. Loureiro (Author) FEUP; Jong-San Chang (Author) Other; Christian Serre (Author) Other; Alexandre F. P. Ferreira (Author) FEUP; Alírio E. Rodrigues (Author) FEUP

Journal

Title: Adsorption

Vol. 24

Pages: 715-724

ISSN: 0929-5607

Publisher: Springer Nature

Indexing

ISI Web of Knowledge - 2 Citations

ISI Web of Science

Scopus - 5 Citations

COMPENDEX

INSPEC

Scientific classification

FOS: Engineering and technology > Chemical engineering

CORDIS: Technological sciences > Engineering > Chemical engineering

Associated Projects

IF/00514/2014/CP1249/CT0004 - Desafiando a síntese em química fina: uma nova abordagem utilizando fotocatalisadores isentos de metais

Other information

Authenticus ID: P-00P-P7E

DOI: 10.1007/s10450-018-9976-8

Abstract (EN): The separation of xylene isomers feedstock containing ethylbenzene is still a relevant industrial challenge. The increase in p-xylene consumption worldwide promotes the search for more efficient separation processes. One possible way to achieve such a goal is to upgrade the existing SMB units with selective adsorbents operating at lower temperatures. Therefore, new adsorbents such as the functionalized metal-organic framework MIL-125(Ti)_NH2 appear as strong candidates. The MIL-125(Ti)_NH2 was tested in this work for the selective adsorption and separation of xylene isomers, including ethylbenzene, in liquid phase and using n-heptane as eluent. In this way, a detailed experimental study of binary and multicomponent adsorption equilibrium of xylene isomers in MIL-125(Ti)_NH2, at three temperatures (299K, 313K and 343K) in liquid phase, was performed and is reported in this manuscript. Ternary breakthrough experiments indicate competitive adsorption between p-xylene over the two other isomers. Indeed the selectivity values range from 1.4 to 1.9 and 1.5 to 2.3 for the p-xylene/m-xylene and p-xylene/o-xylene pairs, respectively, increasing with the temperature. Similar trends are observed for the quaternary mixtures, where p-xylene and ethylbenzene are adsorbed preferentially. However, the MIL-125(Ti)_NH2 does not discriminate between the two more linear molecules at lower temperatures. Yet, when temperature is increased to 343K, the adsorption of p-xylene becomes more favorable than ethylbenzene, presenting a selectivity of 1.3. Therefore, within the studied temperature range a temperature, 343K is the most favorable temperature to operate the SMB process, for the p-xylene production from mixtures containing ethylbenzene.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10