A comparative study of weighted residual methods has been made on different types of advection diffusion equations. Both the linear and non-linear models have been discretized by orthogonal collocation method (OCM) and orthogonal collocation on finite elements (OCFE). Model equations have been solved by MATLAB ‘ode15s’ system solver. Numerical values have been compared with analytic ones and in...

A model Co/SiO2 catalyst was prepared by depositing cobalt on silica films in ultrahigh vacuum conditions. Fischer–Tropsch synthesis was carried out at a total pressure of carbon monoxide and hydrogen between 0.33 and 1.0 bar. The effects of reaction temperature and pressure on kinetics and chain growth probability were investigated. The turnover frequency, activation energy, and product distri...

an extensive study of fischer-tropsch synthesis (fts) on alumina-supported cobalt catalysts promoted with different amounts of ruthenium and rhenium is reported. up to 2 wt% of promoters, are added to the catalyst by coimpregnation. the catalysts are characterized by different methods including: bet physisorption, x-ray diffraction, hydrogen chemisorption, and temperature-programmed reduction. ...

In this paper, we analyse some properties of the orthogonal collocation in the context of its use for reducing PDE (partial differential equations) chemical reactor models for numerical simulation and/or control design. The approximation of the first order derivatives is first considered and analysed with respect to the transfer of the stability properties of the transport component from the PD...

The silylation of SBA-15 enhances the reducibility of cobalt oxides on a SBA-15 supported cobalt catalyst, and consequently increases the catalytic activity for Fischer-Tropsch synthesis of hydrocarbons from syngas and selectivity for longer chain products.

Duckweed biomass is gasified in a thermochemical-based superstructure to produce gasoline, diesel, and kerosene using a synthesis gas intermediate. The superstructure includes multiple pathways for conversion of the synthesis gas to liquid hydrocarbons via Fischer−Tropsch synthesis or intermediate methanol synthesis. Low-temperature and high-temperature Fischer−Tropsch processes are examined us...

The interest in Gas-to-Liquid technology (GTL) is growing worldwide because it involves a two-step indirect conversion of natural gas to higher hydrocarbons ranging from Liquefied Petroleum Gas (LPG) paraffin wax. GTL makes possible obtain clean diesel, naphtha, lubes, olefins, and other industrially important organics gas. This article brief review discussing the state-of-the-art GTL, includin...

The method of orthogonal collocation for solving boundary value problems in ordinary diierential equation is described, and its relationship to classical nite diierence methods is illustrated. Numerical examples demonstrate the capabilities of software based on orthogonal collocation for analyzing nonlinear diierential equations. A new discretiza-tion method for the solution of elliptic partial...

High temperature Fischer-Tropsch synthesis process use fixed fluidized bed as a reactor. In order to understand the flow behavior in the fluidized bed better, the research of how the radial velocity affects the entire flow field is necessary. Laser Doppler Velocimetry (LDV) was used to study the radial velocity distribution along the diameter direction of the cross-section of the particle in a ...