Reclamation and utilization of straw as bioflocculant

To obtain an optimal pretreatment condition for the preparation of bioflocculant from straw, different pretreatment methods were investigated. Different mass percents of acid and alkali were adopted for the pretreatment. Then, the bioflocculant was produced through two-stage fermentation technique. The rough cellulose increased distinctly after alkali treatment, while increased just a little after acid treatment. Heating at high temperature could also enhance the quantity of rough cellulose. The degradation rate of straw could reach up to 72.47% after alkali treatment, while that after acid treatment was 44.06%. In addition, the degradation rate of straw treated by using 0.5% diluted alkali was higher than using 1% diluted alkali. When the microorganisms' availability and the manufacturing were taken into account, pretreatment by using 0.5% diluted alkali was preferable. The bioflocculant rate was up to 90% or more by means of 0.5% diluted alkali pretreatment. Pretreatment was significant for the degradation of straw. After efficient pretreatment, straw could become cheap material for the production of bioflocculant.