Related Experiment Video
Updated: Jun 2, 2026

Facile Preparation of Ultrafine Aluminum Hydroxide Particles with or without Mesoporous MCM-41 in Ambient Environments
Published on: May 11, 2017
Effect of surface acidity and basicity of aluminas on asphaltene adsorption and oxidation
Nashaat N Nassar1, Azfar Hassan, Pedro Pereira-Almao
1Department of Chemical & Petroleum Engineering, Alberta Ingenuity Centre for In-Situ Energy, University of Calgary, Calgary, Alberta, Canada. nassar@ucalgary.ca
Abstract:
This study investigates the effect of surface acidity and basicity of aluminas on asphaltene adsorption followed by air oxidation. Equilibrium batch adsorption experiments were conducted at 25°C with solutions of asphaltenes in toluene at concentrations ranging from 100 to 3000 g/L using three conventional alumina adsorbents with different surface acidity. Data were found to better fit to the Freundlich isotherm model showing a multilayer adsorption. Results showed that asphaltene adsorption is strongly affected by the surface acidity, and the adsorption capacities of asphaltenes onto the three aluminas followed the order acidic>basic and neutral. Asphaltenes adsorbed over aluminas were subjected to oxidation in air up to 600°C in a thermogravimetric analyzer to study the catalytic effect of aluminas with different surface acidity. A correlation was found between Freundlich affinity constant (1/n) and the catalytic activity. Basic alumina that has the lowest 1/n value, depicting strongest interactions, has the highest catalytic activity, followed by neutral and acidic aluminas, respectively.
More Related Videos
Related Concept Videos
Oxidations of Aldehydes and Ketones to Carboxylic Acids
Aldehydes readily undergo oxidation in strong oxidizing agents such as potassium permanganate and chromic acid. The oxidation can also be carried out using mild oxidizing agents such as silver oxide. In fact, aldehydes can be easily oxidized...
Oxidation of Alkenes: Syn Dihydroxylation with Potassium Permanganate
Oxidation of Alkenes: Anti Dihydroxylation with Peroxy Acids
Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
Alkynes to Carboxylic Acids: Oxidative Cleavage
Basicity of Aliphatic Amines
To measure the basicity of amines, two conventions are generally used. The first defines Kb as the basicity constant for the deprotonation reaction of water by the amine, as presented in Figure 1. Conventionally, lower Kb indicates higher...

