还原性有机酸络合铁负载活性炭纤维降解染料废水

Degradation of dye wastewater by reductive organic acids coupled with ferric supported activated carbon fiber

摘要:

采用还原性有机酸与铁离子络合负载活性炭纤维，制备出非均相Fenton催化剂用于去除染料废水中有机污染物。利用还原性有机酸的强还原性，促进Fe3+原位还原为Fe2+；利用活性炭纤维的高效吸附和良好导电性，实现对有机污染物的有效富集和原位降解。采用SEM、FT-IR和ICP-AES对制备出的草酸铁负载活性炭纤维（Oxa-Fe/ACFs-3）进行表征，证明草酸铁络合物均匀负载到活性炭纤维上，其中铁的质量分数为0.96%。Oxa-Fe/ACFs-3活化H2O2降解染料废水的研究表明，50 oC时废水化学需氧量（COD）去除率在100 min内可达62.2%。此外，考察了该催化剂pH适用范围以及重复使用性能。电子顺磁共振波谱仪（EPR）实验表明，Oxa-Fe/ACFs-3促进了H2O2活化产生活性自由基•OH和O2•-，实现对染料废水中有机物降解。通过对比不同还原性有机酸络合铁负载活性炭纤维处理染料废水的性能，说明有机酸还原性增强，有利于提高染料废水COD的去除。

Abstract:

A heterogeneous Fenton catalyst was prepared for the removal of organic pollutants from dye wastewater by using reductive organic acids coupled with iron ions supported activated carbon fiber. The in-situ reduction of Fe3+ to Fe2+ was promoted by the strong reducibility of reducing organic acids. The organic pollutants can be effectively enriched and degraded due to the high adsorption and good conductivity of activated carbon fiber. SEM, FT-IR and ICP-AES were used to characterize the prepared ferric oxalate supported activated carbon fiber (Oxa-Fe/ACFs-3). It was proved that the ferric oxalate complex was uniformly loaded on the activated carbon fiber, and the mass fraction of iron was 0.96%. The degradation of dye wastewater by activating H2O2 with Oxa-Fe/ACFs-3 showed that the chemical oxygen demand (COD) removal of wastewater can achieve 62.2% within 100 min at 50 ℃. In addition, the suitable pH range and reusability of the catalyst were investigated. Electron paramagnetic resonance (EPR) experiments showed that Oxa-Fe/ACFs-3 promoted the activation of H2O2 to generate active radicals •OH and O2•-, which realized the degradation of organic compounds in dye wastewater. By comparing the performance of different reducing organic acids complexed with ferric supported activated carbon fiber in the treatment of dye wastewater, the enhancement of reducibility of organic acids is beneficial for the removal of COD in dye wastewater.