Hydroisomerization n-decane

Hydroisomerization of n-decane. monomethyl isomers (mole-%) (F = 12 10" mole decane h ... 

In terms of hydroisomerization selectivity, it was found that Pt/ZSM-22 exhibits highest selectivity for the conversion of n-alkanes to 2-methyl-branched isomers 308,309). For example, the dibranched isomers from n-decane are particularly rich in 2,7-dimethyloctane. On the other hand, 3-, 4-, and 5-methylnonane isomers are significant even at a low conversion level on Pt/H-USY zeolite. On Pt/H-USY, the composition of the methyl-nonane product fraction approaches thermodynamic equilibrium at medium levels of conversion through methyl shifts. In addition, ethyloctanes are observed as primary products on Pt/H-USY via substituted protonated cyclobutane, but they are absent from the reaction products with Pt/ZSM-5... 

A synergistic effect was observed for the hydroisomerization of n-decane with intimately mixed Pt/ZSM-22 and deep-bed steamed zeolite NH4Y (311). The synergism is rationalized in terms of a two-step isomerization mechanism. Pt/ZSM-22 converts decane selectively into 2-methylnonane, even at high conversion. The Y sieve receives this 2-methylnonane as its feed inside this Pt-free sieve a high concentration of monobranched alkenes will build up. This enhances their subsequent conversion to multibranched alkenes. 

Hydroisomerization/ hydrocracking of n-decane A1 Ga-(Be, M) impr. The order of activity found was USY >A1-Be > Ga-M > Al-M. A direct relationship between catalytic activity and Bronsted acidity associated with the Al and Si in the tetrahedral layers of Be. 52... 

M. Steijns and G. Froment, Hydroisomerization and hydrocracking product distributions from n-decane and n-dodecane, Ind. Chem. Prod. Res. Dev., 20, 654-660 (1981). 

For the hydroconversion of -heptane and n-decane, the group of Jacobs [96,165-169] reported a hnear relation between the rates of hydroisomerization normalized to the concentration of tetrahedral A1 and the concentration of pentacoordinated and tetrahedrally distorted A1 (analyzed by Al MAS NMR) [166]. This emphasizes that the interaction of extraframework aluminum species with Bronsted acid sites creates more active sites. The work by Blomsma et al. [96,165,167] shows that hydroconversion of n-heptane over Pd/H-Beta zeolites is a combination of classic bifimctional hydrocracking and cracking of dimerized C7 species. 

Steyns, M. and Froment, G.F. (1981) Hydroisomerization and hydrocracking Kinetic analysis of rate date for N-decane and N-dodecane , Ind. Eng. Chem. Prod. Res. Develop. 20,660-668. 

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