Effect of acidity and porosity changes of dealuminated mordenite on n-pentane, n-hexane and light naphtha isomerization

State of the Art and Perspectives of Hierarchical Zeolites: Practical Overview of Synthesis Methods and Use in Catalysis

“…This is because a lower total acidity tends to be beneficial in the isomerization of n-hexane, n-pentane, and light naphtha, since higher acidities will lead to cracking. [252] The same improvement is true for the study of Nasser et al wherein acidity decreased as well, compared to the parent zeolite. By consequence, the selectivity to light olefins increased in the conversion of dimethyl ether.…”

“…In contrast to the HCl concentration and single/multistage dealumination parameters, which all showed to have a significant influence on the framework composition and pore characteristics, zeolite/acid volume ratio, agitation, and treatment time did not seem to affect the outcome of the dealumination significantly. However, the effect of treatment time was also investigated by Tamizhdurai et al [252] and Nasser et al [254] during the dealumination of mordenites in a HCl or HNO 3 reflux. Tamizhdurai et al performed an acid treatment for 0.5, 1, and 1.5 h, whereas Nasser et al applied a treatment time between 3 and 6 h. A significant effect of treatment time was observed by the first group, wherein a treatment time of 1 h in 6 N HCl (100 °C) resulted in high porosity, increased external surface area and improved total acidity compared to the parent mordenite without intensively destroying the microporosity.…”

“…[ 251 ] Despite the relatively large 12‐MR pores, MOR zeolites are susceptible to rapid deactivation due to the fact that reactant molecules cannot diffuse into smaller side channels. [ 252 ] It should be mentioned that there exist several material types with MOR topology, although, mordenite zeolites are most familiar and will be mainly discussed in following section.…”

“…However, the effect of treatment time was also investigated by Tamizhdurai et al. [ 252 ] and Nasser et al. [ 254 ] during the dealumination of mordenites in a HCl or HNO 3 reflux.…”

Recent Progress in Synthesis and Application of Nanosized and Hierarchical Mordenite—A Short Review

“…To overcome this problem V.V. Bobik et al [87] and P. Tamizhdurai et al [88] investigated acid (HCl)-treated mordenite as support with deposited metal nanoparticles (Pd and Pt). In these investigations, special attention was paid to the study of the relationship structure (porosity, external acid centers) properties.…”