Precipitation of quercetin and nicotinamide in carbon dioxide + ethanol systems at high pressures: Phase equilibrium data for antisolvent processes

•Precipitation of quercetin and nicotinamide from CO2/ethanol mixtures at various compositions.•Phase equilibrium data for quercetin micronization or co-crystallization with nicotinamide by CO2 antisolvent processes.•Vapor-liquid equilibrium data were fitted by PR-EoS from 308.15 K to 328.15 K.•Solid phase is favored by higher CO2 molar fractions and/or QCN concentrations.•Presence of a solid phase did not alter solvent/antisolvent binary behavior.