Several principles of green chemistry are introduced through this experiment designed for use in the undergraduate analytical chemistry laboratory. An established experiment of liquid CO2 extraction of D-limonene has been adapted to include a quantitative analysis by gas chromatography. This facilitates drop-in incorporation of an exciting experiment into an existing curriculum. The experiment provides an introduction to natural product extraction, calibration curves, and internal standards while simultaneously demonstrating alternative solvent selection for pollution prevention and increased chemical safety.