Open AccessHindered Diffusion of Asphaltenes at Evaluated Temperature and Pressure
Author(s) -
J.A. Guin,
Surya Vadlamani,
Xiafeng Yang
Publication year - 1998
Language(s) - English
Resource type - Reports
DOI - 10.2172/2099
Subject(s) - asphaltene , adsorption , thermal diffusivity , diffusion , atmospheric temperature range , thermodynamics , pellets , chemistry , logarithm , catalysis , constant (computer programming) , coal , chemical engineering , analytical chemistry (journal) , materials science , chromatography , organic chemistry , composite material , mathematical analysis , physics , mathematics , engineering , computer science , programming language
During this time period, uptake experiments were performed at elevated temperatures up to 280 o C for the adsorptive diffusion of a coal asphaltene in 1- methylnaphthalene onto alumina catalyst pellets. Model simulation results showed that a mathematical model incorporating diffusion and adsorption mechanisms satisfactorily fitted the adsorptive diffusion of coal asphaltenes onto the alumina catalyst in a fairly wide temperature range of 55 o C to 280 o C. The logarithm of the adsorption constant, obtained by simulating the experimental data with the model solution, was found to be linearly dependent on temperature. As temperature increased, the value of the adsorption constant decreased. On the other hand, the effective diffusivity of the asphaltene increased with temperature. These off-setting temperature dependencies resulting from the adsorption constant and the effective diffusivity compensated at least to some extent in the uptake process