Chen Jiabin, Hong Wei, Huang Tianyin, Zhang Liming, Li Wenwei, Wang Ying
School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215001, China.
School of Chemistry and Materials Science, University of Science and Technology of China, Hefei, 230026, China.
Environ Sci Pollut Res Int. 2016 Sep;23(18):18564-74. doi: 10.1007/s11356-016-7015-4. Epub 2016 Jun 13.
Activated carbon fiber (ACF) was used as a green catalyst to activate persulfate (PS) for oxidative decolorization of azo dye. ACF demonstrated a higher activity than activated carbon (AC) to activate PS to decolorize Orange G (OG). The decolorization efficiency of OG increased as ACF loading, PS dosage, and temperature increased. OG decolorization followed a pseudo first-order kinetics, and the activation energy was 40.902 kJ/mol. pH had no apparent effect on OG decolorization. Radical quenching experiments with various radical scavengers (e.g., alcohols, phenol) showed that radical-induced decolorization of OG took place on the surface of ACF, and both SO4 (·-) and HO· were responsible for OG decolorization. The impact of inorganic salts was also evaluated because they are important compositions of dye wastewater. Cl(-) and SO4 (2-) exhibited a promoting effect on OG decolorization, and the accelerating rate increased with elevating dosage of ions. Addition of Cl(-) and SO4 (2-) could increase the adsorption of OG on ACF surface, thus favorable for OG decolorization caused by the surface-bound SO4 (·-) and HO·. Conversely, HCO3 (-) and humic acid (HA) slightly inhibited OG decolorization. The azo band and naphthalene ring on OG were remarkably destructed to other intermediates and finally mineralized to CO2 and H2O.
采用活性炭纤维（ACF）作为绿色催化剂来活化过硫酸盐（PS），用于偶氮染料的氧化脱色。ACF在活化PS使橙黄G（OG）脱色方面表现出比活性炭（AC）更高的活性。随着ACF负载量、PS用量和温度的增加，OG的脱色效率提高。OG脱色遵循准一级动力学，活化能为40.902 kJ/mol。pH对OG脱色没有明显影响。用各种自由基清除剂（如醇类、酚类）进行的自由基猝灭实验表明，OG的自由基诱导脱色发生在ACF表面，SO4(·-)和HO·均对OG脱色起作用。还评估了无机盐的影响，因为它们是染料废水的重要成分。Cl(-)和SO4(2-)对OG脱色表现出促进作用，且促进速率随离子用量的增加而提高。添加Cl(-)和SO4(2-)可增加OG在ACF表面的吸附，从而有利于由表面结合的SO4(·-)和HO·引起的OG脱色。相反，HCO3(-)和腐殖酸（HA）对OG脱色有轻微抑制作用。OG上的偶氮键和萘环被显著破坏为其他中间体，最终矿化为CO2和H2O。
