Black mountains sit in Venezuela: 15–30 million t of petroleum coke. It comes from coking the residue of heavy oil. There is no use for it in Venezuela. Export failed: the price of coke is low and logistics are expensive. US sanctions made sales even harder. And new coke is added every day.
The mountains grew for years
After the 2009 fire at the Jose port, exports stopped and coke was piled on open ground. The state oil company has tried for years to cut the stocks, with little progress.
Coke is a tax on heavy oil
Orinoco oil is heavy as tar. It is heated, blended with light oil, the fractions are distilled off, and the residue goes to coking. Up to a third of it comes out as coke by mass: sulfurous, with vanadium and nickel. Not everything is pulled out of the barrel, and the residue turns into coke.
Asphaltenes are the culprit
Asphaltenes are heavy flat molecules with an aromatic core. At 400–500 °C they stick together into coke and take the metals with them. They also block the growth of the mesophase that good carbon is built from. Remove the asphaltenes before coking and no new coke forms.
Vacuum plus TEGA gives more usable oil for US refineries
The feed is dehydrated, then ARBOK-VC separates the light fractions using deep vacuum, with no hydrogen and no consumables: 1–2.5 kWh per tonne against 15–25 at a conventional refinery. The heavy phase of the oil goes onto TEGA, the ARBOK graphene-like material, pure carbon with no silicon or rare earths. The aromatic cores of asphaltenes cling to the graphite surface, and the metals leave with them. One gram of TEGA unfolds to the area of a football field. What remains is deasphalted oil, the light part for the refinery: metals removed, sulfur too.
Each percentage point of yield gives 10 kg of usable oil per tonne of heavy oil. A TEGA dose of 0.1–0.5% is 1–5 kg per tonne of feed. Yield is counted on the original heavy oil, separately from the added light oil.
Nobody has tested this on heavy residue
Carbon additives reduce coking, and asphaltenes bind firmly to graphitic surfaces. Calculations show that among carbon materials, reduced graphene oxide has the highest affinity for asphaltenes. In toluene adsorption tests on graphene, the heaviest and most aromatic molecules land first, exactly the ones that make coke. Carbon black with an MoS₂ catalyst in residue hydrocracking also cuts coking and raises asphaltene conversion. We found no work testing TEGA or graphene on heavy residue. This is our niche.
Next step: R&D on real Orinoco residue
Sorption of asphaltenes on TEGA in a rig that measures yield and energy use. A comparison of usable oil yield with and without TEGA. In each series we measure sulfur and metals in the oil. ARBOK is ready to develop the technology and the complex for a specific plant.
Who will get the heavy oil that leaves no mountains?