Abstract:

In this work, a hydrothermal approach is employed to synthesize γ-Al₂O₃ nanoparticles with an average size of 40 nm which are used as tribocatalyst for Rhodamine B (RhB) dye degradation under the driving of polytetrafluoroethylene (PTFE) stirring disk. The tribocatalytic RhB dye degradation ratio of the synthesized γ-Al₂O₃ nanoparticles is comprehensively characterized and analyzed under the controlled stirring speeds, different dye solution's concentrations and pH conditions. The evaluation on the recyclability of γ-Al₂O₃ nanoparticles has also been done through monitoring the change of RhB dye degradation performance after reusing the catalyst for multiple cycles. The maximum dye degradation ratio of 95% for a 10 mg/L RhB solution is achieved for 3 h tribocatalysis reaction time under the optimization conditions of 600 r/min mechanical stirring speed and the pH of 7. The RhB dye degradation ratio can still keep >90% after recycling \mathrm{\gamma }-\mathrm{A}{\mathrm{l}}_{\mathrm{2}}{\mathrm{O}}_{\mathrm{3}} nanoparticles for five cycles. γ-\mathrm{A}\mathrm{l}₂\mathrm{O}₃ nanoparticles exhibited efficient dye degradation performance and good recycling stability, indicating that they have important application prospects in the tribocatalytic degradation of dye wastewater driven by friction mechanical energy in the collection environment.

Key words: tribocatalytic, mechanical stirring, γ-Al₂O₃ nanoparticles, radical

摘要：

采用水热法制备了一种粒径约为40 nm的γ-Al₂O₃颗粒，并将其作为摩擦催化剂，利用聚四氟乙烯（PTFE）转盘进行机械搅拌。表征并分析了γ-Al₂O₃纳米颗粒在不同转速、RhB浓度和pH条件下，对RhB的摩擦催化降解性能。通过监测多次回收使用后的γ-Al₂O₃纳米颗粒对RhB的降解率变化，来评价其循环使用性能。结果表明，在转速为600 r/min、pH为7的条件下，经过3 h的摩擦催化反应，10 mg/L RhB的降解率可高达95%； γ-Al₂O₃纳米颗粒经过5次回收利用后，对RhB的降解率仍能达到90%以上。γ-Al₂O₃纳米颗粒展现出高效的染料降解性能和良好的回收稳定性，表明其在收集环境中的摩擦机械能驱动摩擦催化降解染料废水方面具有重要的应用前景。

关键词: 摩擦催化, 机械搅拌, γ-Al₂O₃纳米颗粒, 自由基