Abstract Detoxification with Ca(OH)2 has been proved as an effective method for detoxifying various lignocellulosic hydrolysates liquor. The present work aims to study the effect of overliming conditions on synthetic solutions including glucose, xylose, hydroxymethylfurfural (HMF), furfural (FF), and their various mixtures. Experimental design in line with chromatographic analysis was used to explain the influence of three main factors with distinct levels: pH, temperature, and detoxification time. Furans showed stability under all the studied conditions: pH (0.2; 4; 6; 10, and 12), temperature (25 and 60 °C), and detoxification time (15, 30, and 60 min) even after reflux. Xylose and glucose degradation was observed at pH 12 and followed the same pattern at various treatments. These findings are of great importance revealing the influence of sugar degradation products released at pH 12, with a maximum absorbance of 280 nm, and correlating them to furans loss.