玉竹茎秆纳米纤维素制备工艺优化OA

Aiming at the problems of resource waste and environmental pollution caused by discarded Polygonatum odoratum stems after harvest,purified cellulose from P.odoratum stems was used as raw material to prepare nanocellulose by sulfuric acid hydrolysis.The effects of sulfuric acid mass fraction,hydrolysis temperature,hydrolysis time and solid-liquid ratio on the product yield were investigated by single-factor experiments.Combined with the Box-Behnken response surface methodology,the preparation process was optimized,and the structure and properties of the product were systematically characterized.The results showed that the order of influencing factors on nanocellulose yield was sulfuric acid mass fraction>hydrolysis temperature>hydrolysis time>solid-liquid ratio.The optimal preparation conditions were determined as follows:sulfuric acid mass fraction 63.5%,hydrolysis temperature 55℃,hydrolysis time 2.0 h,and solid-liquid ratio 1∶20(g∶mL).Under these conditions,the nanocellulose yield reached 50%±0.25%,which was highly consistent with the model predicted value.