Supercritical CO2 is an interesting medium for supercritical fluid extraction of aromatic molecules, due to the low temperatures and pressures needed to the process. Methanol is often solvated in supercritical CO2 as a modifier, in order to enhance solubility of polar species. The microscopic mechanism of supercritical fluid extraction is largely unknwon. We want to address, through neutron diffraction with isotopic substitution, wether the clustering phenomena for CO2 around methanol and H-bonding between methanol molecules, suggested in NMR literature, are visible.