Recyclable metal-organic framework/cellulose aerogels for activating peroxymonosulfate to degrade organic pollutants
Recyclable metal-organic framework/cellulose aerogels for activating peroxymonosulfate to degrade organic pollutants
复制标题
可回收金属有机骨架/纤维素气凝胶，用于活化过一硫酸盐降解有机污染物
DOI：
10.1016/j.cej.2018.05.143
复制
发表时间：
2018-10-01
影响因子：
15.1
通讯作者：
Yao, Juming
中科院分区：
文献类型：
--
作者：
Ren, Wenjing;Gao, Junkuo;Yao, Juming
金属-有机骨架（MOFs）催化剂活化过硫酸盐（PMS）去除难降解有机污染物的研究已有很多报道，但MOFs呈粉末状，难以从溶液中分离，限制了其应用。本研究首次将咪唑类沸石骨架材料ZIF-9和ZIF-12负载到纤维素气凝胶上，并将其作为金属催化剂，有效地活化PMS降解罗丹明B（RB）、盐酸四环素（TC）和对硝基苯酚（PNP）。复合气凝胶/PMS体系在1h内对水中难去除的PNP的去除率可达90%左右。溶液的pH值对降解过程没有影响，表明杂化气凝胶具有良好的pH耐受性。此外，利用电子顺磁共振（EPR）和自由基捕获技术对PNP的降解机理进行了研究。结果表明，杂化气凝胶能有效活化PMS，产生硫酸根自由基（SO 4中心点-）、羟基自由基（中心点OH），揭示了SO 4中心点-在PMS降解过程中起关键作用。杂化气凝胶最重要的特点是可以很容易地从溶液中分离出来。结果表明，该杂化气凝胶具有良好的可回收性，对降解无明显影响。所制备的杂化气凝胶具有绿色、环境友好、催化效率高等特点。此外，对PNP的优异降解表明了杂化气凝胶作为高级氧化工艺（AOP）催化剂的良好前景。
Metal-organic frameworks (MOFs) as catalysts for the activation of peroxymonosulfate (PMS) to remove recalcitrant organic contaminants has been well reported, however, the separation of MOFs from the solution is difficult because of their powder state, which limits their applications. In the present study, zeolitic imidazole framework (ZIF) materials, ZIF-9 and ZIF-12 were pioneered to load on cellulose aerogels, and the hybrid aerogels as metal catalysts to effectively activate PMS for Rhodamine B (RB), tetracycline hydrochloride (TC) and p-nitrophenol (PNP) degradation. The hybrid aerogels/PMS system could remove PNP about 90% in 1 h, which hard to remove from water. The pH value of the solution had no effect on the degradation process, which demonstrated that the hybrid aerogels had excellent pH tolerance. In addition, the mechanism of PNP degradation was investigated by electron paramagnetic resonance (EPR) and free radical trapping methods. The results showed that PMS could effectively activate by hybrid aerogels to produce sulfate radicals (SO4 center dot- ), hydroxyl radicals ( center dot OH), and revealed that SO4 center dot- play a key role in degradation. The most important feature of hybrid aerogels is can be easily separated from the solution. The obtained results showed that the hybrid aerogels exhibit excellent recyclability, with no significant effect on degradation. The prepared hybrid aerogels are green, environmentally friendly with high catalytic efficiency. Further, the outstanding degradation of PNP demonstrates the promising prospects of hybrid aerogels as advanced oxidation process (AOP) catalysts.