Process and apparatus for extracting aromatic compounds contained in a hydrocarbon feedstock

In a process for extracting a first-liquid comprised of liquid aromatic compounds from a second-liquid comprised of a liquid hydrocarbon feedstock, comprising:

• bringing said second-liquid and a third-liquid into intimate countercurrent contact with each other in an extraction zone to thereby form immiscible phases,
• subsequently separating the immiscible phases to thereby produce a raffinate phase impoverished in aromatic compounds and an extract phase rich in the solvent and the aromatic compounds;
• wherein the improvement comprises:
• the third-liquid being comprised of a solvent which is immiscible with the second-liquid except for being capable of extracting the aromatic compounds;
• the bringing into intimate countercurrent contact of the second- and third-liquids includes bringing the second- and third-liquids in contact with at least one static mixer element comprised of structural packing elements having an axial transmission factor of about 90% in the extraction zone;
• separating by liquid--liquid separation downstream of the extraction zone at least part of the extract phase rich in the solvent and the aromatic compounds, yielding a solvent rich phase essentially depleted of raffinate, and a raffinate rich phase impoverished in solvent;
• and,
• recycling the raffinate rich phase impoverished in solvent to the extraction zone.