活性炭粒径对O3-AC处理有机废水的影响机制

臭氧-活性炭(O₃-AC)技术可以通过吸附和氧化协同作用去除废水中的污染物,而AC粒径是影响这一过程的关键因素。制备了5种48~1700 μm的不同粒径AC用于苯酚废水的O₃-AC处理,通过吸附和氧化动力学考察了AC粒径对污染物的吸附、氧化以及O₃传质的影响机制。结果表明:在AC粒径<150 μm时,AC表面出现更多微观孔道,吸附和氧化速率较粒径>150 μm的AC分别提高了189%和166%;粒径在48~150 μm的AC在O₃中的传质和分解速率分别达到0.57,0.51 min-1,显著高于其他大粒径AC;在O₃-AC中加入叔丁醇(TBA)后,40 min内COD去除率降低了20%,O₃的分解作用与催化氧化反应有关;使用48~150 μm粒径的AC连续进行6次O₃-AC实验,COD去除速率均保持在95%以上,具有良好稳定性。

INFLUENCE MECHANISM OF ACTIVATED CARBON PARTICLE SIZE ON O3-AC TREATMENT OF ORGANIC WASTEWATER

Ozone-activated carbon (O₃-AC) technology can remove pollutants from wastewater through the synergistic effect of adsorption and oxidation, with the size of the AC particle being the key influencing factor. Five different particle sizes in the range of 48~1700 μm were prepared and used for O₃-AC treatment of phenol wastewater. The mechanisms of AC particle size effects on pollutant adsorption, oxidation and O₃ mass transfer were investigated by adsorption and oxidation kinetics. Experimental results showed that when the particle size of AC was below 150 μm, the exposure of more microscopic pore channels on the surface of AC increased the adsorption and oxidation rates by 189% and 166%, respectively, compared to AC with particle size above 150 μm; the mass transfer and decomposition rates of AC with particle size between 48~150 μm in O₃ reached 0.57 min-1 and 0.51 min-1, respectively; after adding tert-butanol (TBA) to O₃-AC, the COD removal rate decreased by 20% within 40 min. The decomposition of O₃ was related to the catalytic oxidation reaction; after six consecutive O₃-AC experiments using 48~150 μm particle size AC, the COD removal rate was maintained at 95% above, showing a good stability.