响应曲面优化柏木屑微波活性炭的制备及其吸附AR88性能

Cypress sawdust based activated carbon preparation and its adsorptive capacity towards macromolecule dye(AR88) : Optimization by surface methodology

以家具制造废弃物——柏木屑为原料,以磷酸为活化剂,采用微波加热方式,选用响应曲面分析法中心复合设计(CCD)对柏木屑活性炭(AC)制备因素进行优化,结果表明,活性炭最佳制备条件为磷酸/柏木屑质量浸渍比1.94∶1,辐照时间8.84 min,微波功率474.98 W,所得活性炭的碘吸附值为945.41 mg·g-1,得率为42.57%。将最优条件制备所得的柏木屑微波活性炭用于大分子染料酸性红88(AR88)的吸附特性研究,实验结果表明,AR88的去除率随着活性炭的投加量增加而升高,活性炭的吸附容量随着AR88浓度的升高而增加。活性炭对AR88的吸附符合Langmuir吸附等温模型,理论最大吸附量为322.58 mg·g-1。对柏木屑微波活性炭物化性质分析表明其表面存在大量无规则孔隙,比表面积、孔容和平均孔径分别为1 312 m2·g-1和0.896 cm3·g-1和2.88 nm。根据吸附结果和表征结果得知,柏木屑微波活性炭是一种具有潜力的高效吸附剂,能有效去除水中的AR88。

Activated carbon （AC） was prepared from furniture manufacturing waste, specifically from cypress sawdust, by phosphoric acid activation in a microwave oven. The response surface methodology （RSM） and cen- ter composite design （CCD） were used to optimize the preparation process of activated carbon. The optimal preparation conditions were： phosphoric acid/sawdust impregnation ratio of 1.94 ： 1, irradiation time of 8.84 min, and microwave power of 474.98 W. Under these conditions, the iodine value and the yield of the activated carbon were 945.41 mg ~ g-~ and 42.57% , respectively. Acid red 88 （AR88） was chosen as the target pollu- tant to study the adsorption performance of the activated carbon produced at optimal conditions. The results showed that the AR88 removal efficiency increased with AC dosage and the AC removal capacity toward AR88 in- creased with higher initial AR88 concentration. The adsorption process fit well with the Langmuir model, with the largest adsorption amount of 322.58 mg · g-1 The carbon characterization shows irregular porosity_ion the -1 carbon surface. The BET value, pore volume, and mean diameter were 1 312 m2· g-1,0. 896 cm3 · g , and 2.88 nm, respectively. Cypress sawdust-based microwave-induced activated carbon is a promising and efficient adsorbent for removing AR88 from aqueous solutions.