Cold Lake asphaltenes

The thermal hydroconversion of Cold Lake asphaltenes was studied initially to provide a basis for evaluation of catalytic effectiveness in subsequent work. Series of thermal runs were made at 335°C, 365°C and 400°C and the reaction products were separated as described previously. Several kinetic models were tried, but after examining the variability of our data, we decided on the simple first-order asphaltene decomposition model shown below ... 

Figure 1. Thermal hydroconversion of Cold Lake asphaltenes at 400°C and 6 MPa H2 asphaltenes ( A) maltenes (O) coke ) model (-).

Figure 3. Arrhenius plot for hydroconversion of Cold Lake asphaltenes 200 ppm molybdenum (A) thermal (0).

Influence of Thermal Processing on the Properties of Cold Lake Asphaltenes The Effect of Distillation... 

Aromatic Carbon and Hydrogen Contents of Cold Lake Asphaltenes... 

ESR Parameters for Cold Lake Asphaltenes Parameter Crude Asphaltenes Residuum Asphaltenes... 

It is apparent from the chemical shifts (g-values), the hyperfine coupling constants (A-values), and the linewidths that the free radicals and vanadyl species are in very similar environments in both samples. It was not possible to obtain meaningful values for the absolute numbers of spins per gram for either species, but estimates of the relative concentrations obtained by measuring peak heights indicate that the vanadyl and free-radical concentrations do not differ significantly between the two asphaltenes. It thus appears that heat treatment of Cold Lake asphaltenes to 320°C does not alter the nature or abundance of paramagnetic centers. 

Schucker, R.C., Keweshan, C.F. 1980. Reactivity of cold lake asphaltenes. Prepr. Pap. Am. Chem. Soc. Div. Fuel Chem. 25 155-165. 

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