Abstract:

The effective green regeneration of saturated activated carbon is very important for the recycling of activated carbon in the process of pollutant adsorption. In this paper, the method of ultrasonic assisted melting oxalic acid was used to regenerate the saturated activated carbon with high efficiency and green. The effects of temperature, time, ultrasonic amplitude and solid-liquid ratio on the regeneration efficiency of saturated activated carbon were discussed. The results showed that the saturated activated carbon can be regenerated rapidly in 20 minutes by molten oxalic acid under the assistance of ultrasound and the regeneration efficiency was as high as 94.72%. After five adsorption desorption cycles, the regeneration efficiency can still reach 78.02% and the recovery rate of organic acids was very high with an average of 98.35%, and thus green regeneration was realized. Under the assistance of ultrasound, the molten oxalic acid with strong hydrogen bond association ability reacted more fully with caramel to form a strong hydrogen bond association system between oxalic acid and caramel, which reduced the affinity between caramel and activated carbon surface. Then, the adsorbate can be desorbed to achieve the regeneration of the activated carbon. This method can provide a new idea for the research and development of green and efficient activated carbon regeneration method.

Key words: activated carbon, regeneration, ultrasound-assisted, solid organic acid

摘要：

饱和活性炭的高效绿色再生对活性炭在污染物吸附过程中的循环利用是非常重要的。本文利用超声波辅助熔融草酸的方法对饱和活性炭进行高效绿色再生，讨论了温度、时间、超声振幅和固液比对饱和活性炭再生效率的影响。结果表明，在超声辅助作用下，熔融草酸可在20min内使饱和活性炭得到快速再生，再生效率高达94.72%。通过5次吸附-脱附循环后，再生效率仍可达到78.02%，与此同时有机酸的回收率极高，平均达到98.35%，再生过程十分绿色环保。在超声的辅助作用下，强氢键缔合能力的熔融草酸更充分地与焦糖反应，形成草酸-焦糖强氢键缔合体系，降低焦糖与活性炭表面的亲和力，将焦糖解吸，实现活性炭的再生。该法可为绿色高效的活性炭再生方法的研究开发提供新思路。

关键词: 活性炭, 再生, 超声辅助, 固体有机酸