The hydrogenolysis of n‐butane on a nickel on silica catalyst: I A Kinetic model

Abstract

The catalytic hydrogenolysis of n-butane was investigated in an integral packed bed reactor (0.70 mi. ID by 25 cni. long). The catalyst was 105; nickel on silica gel. A block factorial set of experiments was performed at hydrogen-to-butane feed ratios of 4. to 9., temperatures of 240% to 282OC and feed flowrates of 1.0 to 1.8 ml/sec. T h e predominant reaction appeared to be the r e m a d of terminal methyl groups.Kinetic rate expressions were developed to predict the product distribution, taking into account a five-fold change in catalytic activity. A parameter estimation strategy, applying non-linear regression theory, was used to obtain the ten kinetic parameters. Error analysis of the parameters was performed using likelihood ratios. Models were developed to describe the catalyst activity changes observed during experinrentation. The kinetic model predicts the experimental observations very accurately over all conversions and shows some deviation only a t the combination of high temperature and low feed ratio.nvestigations have been reported in the literature

Collocation methods for solving packed bed reactor models with radial gradients

“…Kinetic expressions for the net rates of disappearance or appearance of each species in the gas phase have been developed by Orlickas et al (1970Orlickas et al ( , 1972 and Shaw et al (1972Shaw et al ( , 1974. This is represented by the following series-parallel set of reactions: There are three stochiometrically independent species, the other two being dependent upon these.…”

“…This is represented by the following series-parallel set of reactions: There are three stochiometrically independent species, the other two being dependent upon these. Kinetic expressions for the net rates of disappearance or appearance of each species in the gas phase have been developed by Orlickas et al (1970Orlickas et al ( , 1972 and Shaw et al (1972Shaw et al ( , 1974. The rate expressions are very non-linear in concentration and temperature (the rates double approximately every 6.5"K).…”

Control of fluidized bed reactors. 1. Modeling, simulation, and single-loop control studies

“…The reactions considered are those of the hydrogenolysis of normal butane in a fluidized bed of nickel-impregnated silica gel catalyst. The butane hydrogenolysis reactions were extensively studied by Orlikas et al (1972). They showed 0196-4305/83/1122-0022$01.50/0 © 1982 American Chemical Society that these highly exothermic hydrogenolysis reactions could be represented by the following set of four seriesparallel equimolar reactions (three of which are stoichiometrically independent) C4H10 + h2-> C3H8 + CH4 C4H10 + H2 -* 2C2H6 c3h8 + h2 -c2h6 + ch4…”

“…Reaction Kinetics. Orlikas et al (1972) developed a mechanistic kinetic model for the reaction system described in eq 1 and showed that it gave very good predictions of conversion and selectivities over a wide range of conditions. These expressions and their parameters were used directly in this study.…”

“…Although many of the parameters in the foregoing model were readily available in the literature, or had been previously well estimated from statistically designed kinetic experiments (Shaw et al, 1972;Orlikas et al, 1972) still remained a number of unknown parameters that had to be estimated from data collected on the fluidized bed reactor itself. These are listed in Table I.…”