Abstract:
As a toxic Volatile Organic Pollutant (TVOC), formaldehyde has a toxic effect on microorganisms, consequently inhibiting the biochemical process of formaldehyde wastewater treatment. Therefore, the selective degradation of formaldehyde is of great significance in achieving high-efficiency and low-cost formaldehyde wastewater treatment. This study constructed a heterogeneous Fe-ZSM-5/H2O2 Fenton system f or the selective degradation of target compounds. By immobilizing Fe3+ onto the surface of a ZSM-5 molecular sieve, Fe-ZSM-5 was prepared successfully. XRD, BET and FT-IR spectral studies showed that Fe-ZSM-5 was mainly composed of micropores. The influences of different variables on formaldehyde-selective heterogeneous Fenton degradation performance were studied. The 93.7% formaldehyde degradation and 98.2% selectivity of formaldehyde compared with glucose were demonstrated in the optimized Fenton system after 360 min. Notably, the resultant selective Fenton oxidation system had a wide range of pH suitability, from 3.0 to 10.0. Also, the Fe-ZSM-5 was used in five consecutive cycles without a significant drop in formaldehyde degradation efficiency. The use of reactive oxygen species scavengers indicated that the hydroxyl radical was the primary active species responsible for degrading formaldehyde. Furthermore, great degradation performance was acquired with high concentrations of formaldehyde for this system, and the degradation efficiency was more than 95.0%.
摘要:
作为一种有毒的挥发性有机污染物(TVOC),甲醛对微生物有毒性作用,从而抑制了甲醛废水处理的生化过程。因此,甲醛的选择性降解对实现高效、低成本的甲醛废水处理具有重要意义。本研讨构建了非均相Fe-ZSM-5/H2O2Fenton体系以选择性降解目标化合物。通过将Fe3+固定在ZSM-5分子筛的表面,成功制备了Fe-ZSM-5。XRD,BET和FT-IR光谱研究表明Fe-ZSM-5主要由微孔组成。研究了不同变量对甲醛选择性非均相Fenton降解性能的影响。在优化的Fenton系统中360分钟后,与葡萄糖相比,甲醛降解率为93.7%,甲醛选择性为98.2%。值得注意的是,所得到的选择性Fenton氧化体系具有广泛的pH适用性,从3.0到10.0。此外,Fe-ZSM-5在五个连续循环中使用,而甲醛降解效率没有显著下降。活性氧物质清除剂的使用表明羟基自由基是负责降解甲醛的主要活性物质。此外,该系统在高浓度甲醛的情况下获得了巨大的降解性能,降解效率达95.0%以上。