Fe@AM3吸附耦合VUV-SO_(3)^(2-)光还原降解水中全氟己烷磺酸效能研究

Study on the Efficiency of Fe@AM3 Adsorption Coupling VUV-SO_(3)^(2-) Photoreduction Degradation of Perfluorohexane Sulfonic Acid in Water

本研究采用氨基化磁性介孔微球(Fe@AM3)吸附耦合紫外光还原降解技术去除水中全氟己烷磺酸(PFHxS),对其不同处理阶段去除效能和机理进行系统研究。研究表明,pH=3时,Fe@AM3对PFHxS的吸附效果最佳,其残留率低至8.5%;PFHxS在pH=10.5时可以很好地从PFHxS上实现脱附,其脱附率高达95.2%;同时,表现出良好的可重复利用性,重复利用4次后对PFHxS的吸附率仍可达到75%。对比不同光还原降解体系,VUV-SO_(3)^(2-)具有最优的PFHxS降解(78.2%)和脱氟(54.9%)效果;进一步优化该降解体系,发现选用N2氛围,提高pH值(10.5)或亚硫酸盐浓度(20 mmol/L)均有利于降解效果提升;光还原降解过程中eaq-是主要活性物种,增大eaq-含量可提高脱氟率。

In this study, PFHxS in water was removed by aminated magnetic mesoporous microsphere(Fe@AM3) adsorption coupled with UV photoreduction degradation technology, and the removal efficiency and mechanism of PFHxS in different treatment stages were systematically studied. The research showed that when pH=3, the adsorption effect of PFHxS by Fe@AM3was the best, and its residual rate was as low as 8.5 %. PFHxS could be commendably desorbed from Fe@AM3at pH=10.5, and the desorption rate was 95.2 %;At the same time, it showed good reusability, and the adsorption rate of PFHxS could still reach 75 % after 4 times of reuse. Compared with other different photoreduction degradation systems, VUV-SO_(3)^(2-)showed the best PFHxS degradation(78.2 %) and defluorination(54.9 %) effects;Further optimizing the degradation system, it was found that selecting N2atmosphere, increasing pH value(10.5) or sulfite concentration(20mmol/L) were beneficial to the improvement of degradation effect;Eaq-was the main active species in the process of photoreduction degradation.