The composition of degraded hemicelluloses liquor obtained from organic acid fraction of the raw material is very complex and various pretreatments are needed for further fermentation. Especially many components that are inhibitory to microorganism should be removed. The hemicelluloses liquor from Milox pulping of reed was pretreated with powered activated carbon aimed at lowering the content of formic acid, and the remaining sugar fraction was subjected to lactic acid fermentation by Lactobacillus pentosus. Nearly complete conversion of sugars was achieved, i. e., the product contained 33 g/l lactic acid and 17 g/l acetic acid with volumetric productivity of 0.6 g/(l h) [121] .

Xylose can be produced by hydrolysis of straw with formic acid containing hydrochloric acid. In a previous study, the straw was hydrolyzed with saturated formic acid containing 10% HCl with a liquor solid ratio of 24 in 0.5 h at 65°C, to obtain xylose with yield of 23.62% [122]. The hydrolyzate was purified with D311 and activated carbon for decoloration and then crystallized, resulting in a pure xylose fraction with a yield of 15.87%.