微波辐照再生颗粒活性炭(GAC)的研究

Microwave irradiation for regeneration of granular activated carbon(GAC)

研究了活性炭在微波场中的温升行为和脱水行为,并对该行为进行了定量描述.通过正交实验,探讨了活性炭的再生效果与微波辐照的功率、时间、活性炭吸附量等因素的关系.研究了微波辐照对活性炭表面酸碱官能团的影响,并对微波辐照再生活性炭前后孔隙结构进行了对比.结果表明,微波辐照几分钟内活性炭表面可达1000℃.对再生后活性炭碘值影响最大的因素是辐照时间,从碘值来看400W,2min再生效果好.Boehm滴定说明微波作用可以增加JX-206型果壳炭表面的碱性基团,降低其表面酸性基团,使其PZC明显增大.与废弃活性炭相比,微波辐照后的活性炭比表面积、孔容积都增加了100%左右,且微波主要作用于直径小于5nm的活性炭孔.

The behaviors of heating-up and drying of activated carbon by microwave irradiation were： studied and described quantitatively. The relationship between regeneration efficiencies of GAC and those factors such as microwave power, irradiation time and dose absorbed by GAC was derived and analyzed through orthogonal test. The influence of MW treatment on the acidic and basic groups of GAC was studied; the pore structures of exhaust GAC and MW treated, GAC were compared. Results show that the temperature of GAC can reach 1000 ℃ by MW irradiation in a few minutes. The main factor affecting the iodine amount is irradiation time and the optimal regeneration conditions are 400 W and 2 min. The surface acidic,groups are removed due to their decomposition, and the basic characteristic becomes prominent. Compared with exhaust GAC, the specific area and pore volume both increase by 100%. Moreover, MW mostly affects the pores with diameter less than 5 nm. The experiment shows that the microwave irradiation method is practical for regeneration of activated carbon.