The kinetics and mechanism of the reaction between steam and hydrocarbons over nickel catalysts in the temperature range 350?500 $deg;C, part 1

Phillips, T. R.

doi:10.1016/0021-9517(69)90285-1

Cited by 27 publications

(6 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In tests at 350°C to 450°C, Phillips, Mulhall, and Turner (1969) found normal paraffins to be the most reactive for steam reforming, followed by branched hydrocarbons and cycloparaffins, with benzene being the least reactive. As previously indicated, a similar trend was noted in the PNL studies as hexane was converted most rapidly and benzene was the slowest.…”

Section: Cnhm + N H 2 0 • Nco + (N+ 2) Hmentioning

confidence: 98%

“…With normal paraffins, a stepwise degradation has been found in the temperature range of 250°C to 450°C with the nickel selectively attacking the ends of the chain until all of the carboncarbon bonds are broken (Rostrup-Nielsen 1975;Phillips, Mulhall, and Turner 1969). The surface radicals, which are formed when the carbon-carbon bond ruptures, react with adsorbed water to produce CO and H2.…”

Section: Cnhm + N H 2 0 • Nco + (N+ 2) Hmentioning

confidence: 99%

See 1 more Smart Citation

Catalytic destruction of hazardous organics in aqueous solutions

Baker¹,

Sealock²

1988

View full text Add to dashboard Cite

Section: Cnhm + N H 2 0 • Nco + (N+ 2) Hmentioning

confidence: 98%

Section: Cnhm + N H 2 0 • Nco + (N+ 2) Hmentioning

confidence: 99%

Catalytic destruction of hazardous organics in aqueous solutions

Baker¹,

Sealock²

1988

View full text Add to dashboard Cite

“…Steam reforming of natural gas, mainly methane, has been widely studied in different reactor configurations. ,− However, the feedstock for hydrogen production varies from place to place because of the availability of hydrocarbons. , Recent years have shown progress in steam reforming technology, resulting in cheaper plants and higher feedstock flexibility because of the better materials used for reforming reactors, better control of coking, and better reforming catalysts . Steam reforming of higher hydrocarbons is of great importance for hydrogen production not only as a novel fuel, but also in the traditional chemical and petrochemical industries. ,,− Usually, steam reforming of higher hydrocarbons can be represented by the following reactions 3 …”

Section: Introductionmentioning

confidence: 99%

Nonmonotonic Behavior in Hydrogen Production from the Steam Reforming of Higher Hydrocarbons in a Circulating Fluidized Bed Membrane Reformer

Chen

Yan

Elnashaie

2003

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

The nonmonotonic behavior observed in hydrogen production from the steam reforming of higher hydrocarbons over nickel catalyst in an earlier-suggested novel circulating fast fluidized bed membrane reformer (CFFBMR) (Chen et al. AIChE J. 2003, 49 (5), 1250-1265) is extensively investigated. The investigation is carried out using kinetic model simulation at 623-823 K and 1013 kPa. Hydrogen-permselective membranes are used under cocurrent and countercurrent operations. The results show that the yield of hydrogen decreases at 623-723 K and then increases at 723-823 K. At 623 K, heptane is not fully converted, and thermodynamic equilibrium is not established. In contrast at 723-823 K, heptane is fully converted, and thermodynamic equilibrium is established. The strong methanation reaction at 723 K makes the hydrogen yield much lower, whereas at 823 K, the steam reforming of methane becomes increasingly important, enhancing the production of hydrogen. Using hydrogen-permselective membranes, the thermodynamic equilibrium limitation is "broken", and the CFFBMR performance is significantly improved. However, because of the small or negative driving force for hydrogen permeation under cocurrent operation, the hydrogen yield at 723 K is still lower. To improve this process, countercurrent operation is further investigated and found to be more efficient for hydrogen production when hydrogen-permselective membranes are used at 723-823 K. The purity of the exit hydrogen in the membranes is 90.65 and 92.83 mol % for cocurrent and countercurrent operations, respectively, at 823 K. If the sweep gas steam is further condensed, the purity of hydrogen could be as high as 99.45 and 99.59 mol %, respectively.

show abstract

“…To reduce the complexity of reactions, the high number of components can be aggregated into lower sets or lumps of pseudocomponents such as naphthenic, paraffin, aromatic and light hydrocarbons, and so on following some criteria . For this reason, n -heptane is the hydrocarbon typically used in research works. ,− However, one can see studies involving the use of n -hexane, or the mixture of n -hexane and n -heptane, or iso-octane. , In this work, naphtha was represented by n -heptane. The kinetic model of Tøttrup was used to simulate the catalytic steam reforming of n -heptane.…”

Section: Model Developmentmentioning

confidence: 99%

Analysis and Simulation of Catalytic Steam Prereforming of Hydrocarbons in Adiabatic Tubular Reactors

Oechsler

Lima

Dutra

et al. 2020

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

This work presents a dynamic model describing the catalytic steam prereforming of hydrocarbons (natural gas and naphtha) in adiabatic packed-bed tubular reactors. Pre-reforming is an additional step typically used in hydrogen industrial sites before steam reforming to reduce the catalyst deactivation. The proposed model comprises a set of differential equations, based on the momentum, energy, and mass balances, describing the reactions performed in a fixed catalyst-bed reactor, where hydrocarbons and water are mainly converted into a mixture of hydrogen and carbon oxides. The effect of operating conditions such as the steam/ carbon and hydrogen/hydrocarbon ratios on the conversion, temperature, and composition stationary profiles was analyzed for both natural gas and naphtha catalytic prereforming. Besides, the consistency of temperature and composition axial profiles were analyzed via comparison with the adiabatic temperature and composition computed from thermodynamic equilibrium. Simulated results indicated that the proposed model can accurately describe the steam prereforming process operating with both natural gas and naphtha. The main results showed that proper modeling of the effectiveness factor for natural gas and naphtha prereforming is an important task in the industrial operation of these reactors. Additionally, the simulated results showed that these reactors operate close to thermodynamic equilibrium at the beginning of the campaign, as seen at industrial sites. Besides, only methanation and water−gas-shift reactions seem to be controlled by the diffusive effects.

show abstract

The kinetics and mechanism of the reaction between steam and hydrocarbons over nickel catalysts in the temperature range 350?500 $deg;C, part 1

Cited by 27 publications

References 6 publications

Catalytic destruction of hazardous organics in aqueous solutions

Catalytic destruction of hazardous organics in aqueous solutions

Nonmonotonic Behavior in Hydrogen Production from the Steam Reforming of Higher Hydrocarbons in a Circulating Fluidized Bed Membrane Reformer

Analysis and Simulation of Catalytic Steam Prereforming of Hydrocarbons in Adiabatic Tubular Reactors

Contact Info

Product

Resources

About