硼酸催化制备木屑活性炭工艺及孔结构特征

Pore texture of activated carbon from sawdust by boric acid catalysis

以木屑为原料,磷酸为活化剂,硼酸为催化剂制备活性炭。通过正交实验考察了活性炭制备过程中磷屑比、硼酸添加量,活化温度和活化时间等因素对活性炭性能的影响。实验结果表明:生产活性炭的最佳工艺条件为磷屑比为1.5∶1,硼酸的添加量为1%,活化温度是400℃,活化时间为60 min,此时活性炭的得率为33.5%,亚甲基蓝吸附值为225 mg/g,碘吸附值为855 mg/g。添加硼酸的制备方法要比传统的用磷酸制备时的条件更加温和,通过调整工艺条件,可以改变活性炭产品的孔隙结构,生产出用于不同环境的液相吸附专用活性炭。

Activated carbons were prepared from sawdust by means of phosphoric acid and boric acid activation.The effects of phosphoric acid-to-sawdust mass ratio,the amount of boric acid,activation temperature and activation time on properties of the products were investigated by orthogonal experiments.The results showed that the optimum activation process could be achieved when the phosphoric acid-to-sawdust mass ratio was 1.5∶1,and boric acid weight percent was 1% at an activation temperature of 400 ℃ and duration of 60 min.Under such conditions,the product yield was 33.5%,and adsorption value of methyleneblue and iodine was 225 mg/g and 855 mg/g,respectively.The reaction was more moderate in the presence of boric acid compared with the classical phosphoric acid method.Pore structure could be changed by adjusting process parameters to produce appropriative activated carbon applied to liquid adsorption in various environments.