Farayandno

Farayandno

Investigating Zeolite Catalysts Toward Isomerization of Xylenes

Document Type : Review

Authors
آرمان میرچی 1
Mohammad Kaemeini 2
Saeed Soltanali 3
S. Reza Seif Mohaddecy 4
1 PhD. Student, Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran
2 PhD. Professor, Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran
3 PhD. Associate Professor, Catalyst Technology Development Division, Research Institute of Petroleum Industry, Tehran, Iran
4 MSc. Instructor, Catalyst Technology Development Division, Research Institute of Petroleum Industry, Tehran, Iran
10.22034/farayandno.2025.2047525.1982
Abstract
Given the importance and high demand for para-, meta-, and ortho-xylenes, they are isomerized to produce para-xylene in xylene isomerization units. Amongst different catalysts used in this process, zeolites with medium pore size show high efficiency due to their unique shape-selective properties, which further are significantly important in reducing xylene loss as well. Moreover; numerous methodologies have been investigated to enhance catalyst efficiency in the xylene isomerization reaction, increase para-xylene yield, and reduce xylene loss. In this context, several surface modification methods, such as chemical liquid deposition of silica, dealumination, and pre-coking through passivating non-selective acidic sites on the external surfaces of catalysts, lead to reduced xylene loss and increased para-selectivity, rather effectively. On the other hand, using different structures of zeolites and metallic components, as well as hierarchical structures has proved effective in improving the performance of the xylene isomerization process. This article examines the most significant studies conducted to develop optimal catalysts for the xylene isomerization process, aiming to increase paraxylene productivity and minimize xylene loss.
Keywords
Xylene Isomerization
MFI Zeolite
Shape-Selectivity
Surface Modification Methods
Hierarchical Structures

Subjects

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