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7733891 
Journal Article 
Characterization of shape selective properties of zeolites via hydroisomerization of n-hexane (vol 164, pg 71, 2012) 
Chen, CY; Ouyang, X; Zones, SI; Banach, SA; Elomari, SA; Davis, TM; Ojo, AF 
2013 
1 
Microporous and Mesoporous Materials
ISSN: 1387-1811 
Elsevier B.V. 
169 
248-248 
English 
WOS:000314384800035 
Paragraph under Table 3 is missing some text. The paragraph portion has been reproduced for your convenience. At low temperatures, the hydroisomerization is the only reaction. When the reaction temperature increases, the hydrocracking reaction takes off and its yield and selectivity go up. With the competing cracking reaction occurring, as the temperature increases, the yield and selectivity to hydroisomerization products increase initially, proceed to a maximum and then decrease. This is a common phenomenon which occurs with the hydrocracking and hydroisomerization of normal alkanes (e.g., in Ref. [34]) and is also demonstrated with other zeolites in Figs. 3–10 and Supporting information Figs. S1–S3. The cracking products consist predominantly of propane because the formation of methane and pentanes as well as ethane and butanes involves primary carbenium ions and are energetically less favorable than the formation of propane according to Fig. 1. The distribution of the C6 isomers reveals how the hydroisomerization proceeds vs. the reaction temperature. Fig. 2 indicates that n-hexane is isomerized only to 2- and 3-methylpentane at low temperatures. As the temperature increases, 2- and 3-methylpentane are further isomerized to 2,2- and 2,3-dimethylbutane toward the thermodynamic equilibrium. Limited by the thermodynamics under the conditions employed in our studies, the yield of each individual branched isomer of n-hexane has the following order at and above the temperature for the maximum total isomer yield (78.6 mol.% at 293 °C for mordenite): 2-methylpentane (RON 73.4) > 3-methylpentane (RON 74.5) > 2,2-dimethylbutane (RON 91.8) > 2,3-dimethylbutane (RON 101.0). It is important to point out that the yield ratio of 2,2- to 2,3-dimethylbutane is about 2 at the maximum total isomer yield for mordenite (Fig. 2 and Table 4). © 2012 Elsevier Inc.