Siberian Federal University

Due to the shortage of traditional cellulose-containing raw materials, the search for new sources of cellulose is of paramount importance. The aim of the work was to obtain cellulose from flax straw by a modified alkaline method. The effect of the concentration of sodium hydroxide solution, duration and temperature on the yield and properties of the target cellulose is investigated. Optimal conditions of alkaline treatment were established: sodium hydroxide concentration – 4 %; temperature – 90–95 °C; duration – 4 hours. Under the developed conditions, a sample of cellulose was obtained with a yield of 39.5 % in terms of feedstock, while the mass fractions of α-cellulose were 87.5 %, acid–insoluble lignin was 2.60 %, ash was 0.30 %, pentosans were 4.7 %, and the degree of polymerization was 550. The ways of using cellulose from flax straw as a component in composite paper, where high strength of the product is not required, are proposed