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Focused beam reflectance measurement (FBRM) and 13C nuclear magnetic resonance (13C NMR) analysis were used to study the precipitation process of CO2-1oaded potassium glycinate (KGLY) solutions at different CO2 loadings,during the addition of ethanol as an antisolvent at a rate of 10 mL· min-1.The volume ratio of ethanol added to the KGLY solution (3.0 mol· L-1,340 mL) ranged from 0 to 3.0.Three solid-liquid-liquid phases were formed during the precipitation process.The FBRM results showed that the number of particles formed increased with CO2 loading and ethanol addition for CO2-unsaturated KGLY solutions,whilst for CO2-saturated KGLY solution it first increased then decreased to a stable value with ethanol addition.13C NMR spectroscopic analysis showed that the crystals precipitated from the CO2-unsaturated KGLY solutions consisted of glycine only,and the quantity crystallised increased with CO2 loading and ethanol addition.However,a complex mixture containing glycine,carbamate and potassium bicarbonate was precipitated from CO2-saturated KGLY solution with the maximum precipitation percentages of 94.3％,31.4％ and 89.6％,respectively,at the ethanol volume fractions of 1.6,2.5 and 2.3.