硫酸根自由基对活性炭吸附刚果红的影响

本研究通过研究硫酸根自由基（SO₄^-·）对活性炭吸附性能的影响来探究SO₄^-·活化再生活性炭的可行性.结果证实，当刚果红溶液浓度为100mg/L，活性炭加入量为1.25g/L时，活性炭对刚果红的吸附量为62mg/g.体系pH值、KH₂PO₄和K₂HPO₄对活性炭吸附刚果红效果影响较小.当体系中过硫酸钠加入量为刚果红浓度的12倍时，过硫酸钠联合活性炭对刚果红去除率仅比活性炭单独吸附的对照处理提高5%；然而，在水浴锅加热条件下，70℃热活化过硫酸钠在30~120min对刚果红的去除率可达94%~99%；70℃热活化过硫酸钠联合活性炭处理在对应时间段对刚果红的去除率为91%~94%，紫外光活化过硫酸钠联合活性炭处理在对应时间段对刚果红的去除率仅为86%~90%.由此可知，热活化和紫外光活化过硫酸盐产生SO₄^-·对活性炭的吸附性能影响较小，基于硫酸根自由基的高级氧化技术再生活性碳的可能性不大.

Effect of sulfate radical on adsorption of Congo red by activated carbon

The feasibility of activated carbon regeneration by sulfate radical (SO₄^-·) activation was explored by studying the effect of SO₄^·- on the adsorption performance of activated carbon on Congo red. The results confirmed that when the concentration of Congo red solution was 100mg/L and the amount of activated carbon was 1.25g/L, the Congo red adsorption efficiency by activated carbon was 62mg/g. The pH value of the solution and KH₂PO₄ and K₂HPO₄ dissolved in the solution have little effect of the adsorption of Congo red by activated carbon. Compared with Congo red removed by activated carbon alone, the removal efficiency of Congo red merely increased by 5% when the persulfate sodium added into systems with the amount of sodium pecould rsulfate was 12 times of Congo red concentration. However, the removal efficiency of persulfate sodium to Congo red could reach 94%~99% at 30~120min at 70℃ under the heating condition in water bath. The removal efficiency of Congo red in the same corresponding time period was 91%~94% when the Congo red removed by the combined action of activated carbon and persulfate sodium under 70℃. However, the removal efficiency of Congo red in the same corresponding time period was 86%~90% when the Congo red removed by the combined action of activated carbon and Ultraviolet rays (UV) under 70℃. It coudl be seen that SO₄^-·have little effect on the adsorption performance of activated carbon. Therefore, it is not feasible to regenerate activated carbon via the advanced oxidation technology of SO₄^·-.