Abstract: In order to get natural cellulose of high water absorbent ability, the extraction condition of cellulose from citrullus lanatus by chemical separation technique was studied systematically in this paper. The factors which were NaOH mass fraction, H2O2 mass fraction, reaction temperature and reaction time affecting the extraction of citrullus lanatus were researched. The results of the orthogonal experiments showed that the optimum parameters were as follows: NaOH mass fraction was 4%, H2O2 mass fraction was 10%, reaction temperature was 60℃, reaction time was 30min.The mass fraction of the sample citrullus lanatus under the optimum condition was 86.52%. The SEM image showed that citrullus lanatus cellulose had special hollow structure; infrared spectrum analysis confirmed citrullus lanatus extract was cellulose. Absorption liquid ratio test showed that, when water temperature was 40oC and Na + concentration was 0.1mol/L, the water absorption rate of citrullus lanatus can reach 85 g/g, which improved significantly compared with the water absorption rate of natural cotton cellulose (40 g/g).

Key words: Citrullus lanatus cellulose, chemical separation technique, structure, water absorbent property