NiWMo submicronic catalysts from emulsified metallic aqueous solutions were tested for Athabasca bitumen upgrading. The experiments were performed in a batch reactor (100 mL capacity) at a total pressure of 3.45 MPa, a stirring speed of 500 rpm, reaction times of 3−70 h, and temperatures from 320 to 380 °C. Ultradispersed (UD) catalysts enhanced the upgrading of Athabasca bitumen by increasing the hydrogen/carbon ratio and reducing both viscosity and coke formation. The conversion of bitumen increased with both the temperature and reaction time, whereas viscosity, sulfur, and microcarbon residue (MCR) in the reaction products decreased. Catalytic particles tend to agglomerate and become incorporated within the incipient coke matrix that develops at a residue conversion beyond 50 wt %. Nevertheless, good properties of upgraded oil (API gravity, 16°; viscosity at 40 °C, 60 cP; and MCR, 11.1 wt %) are obtained during processing before the onset of solids precipitation.

Typically, the catalytic upgrading of heavy fractions (VGO and VR) has been studied using mostly conventional supported catalysts at temperatures and pressures higher than 400 °C and 6 MPa, respectively. This work focuses on the upgrading of heavy oils at much lower severity conditions using dispersed NiWMo catalysts for processing whole oil with no fractionation. A kinetic study was developed to determine parameters from experimental data obtained at temperatures of 320À380 °C and reaction times from 3 to 70 h at a total hydrogen pressure of 3.45 MPa and a stirring speed of 500 rpm in a batch reactor. The conversion, estimated as the reduction of the residue 545 °C+ fraction, was fitted for a first-order reaction with an apparent activation energy of 200 kJ mol À1 . Two kinetic models are proposed to predict the conversion of the residue fraction and its product distribution. Comparison between experimental data and predictions using the proposed models exhibited good agreement with average absolute errors lower than 5%.

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Large reserves of heavy crude oil and bitumen are waiting for novel technical recovery developments. Nevertheless, the very low API gravity and impurities such as sulphur and nitrogen of the reserves, influences the economics of their industrial utilization. In situ catalytic upgrading of heavy oil and bitumen has been proposed and tested in laboratory scale experiments. Experimental evidence from laboratory scale tests are very promising and this novel technique can play an important role in the exploitation of huge resources of heavy oil and bitumen. Accurate analytical and numerical modeling is essential in order to correctly interpret experimental measurements of the in situ upgrading. This work will enhance the understanding and design of field scale processes. In this paper, simulation results of bitumen ultra-dispersed catalytic upgrading experiments in a batch reactor area reported. The results show that ultra-dispersed catalytic upgrading results in relatively high residue conversion and can potentially increase the API gravity of the produced oil. These results hold significant promise for upgrading heavy crude oils and bitumen using an ultra-dispersed catalyst.