超声强化Fe^0去除阳离子红GTL的研究

Study on the use of ultrasound to enhance removal of cationic red GTL by zero-valent iron

采用US/Fe0系统去除阳离子红GTL,考察了pH值、Fe0用量、超声功率及活性炭、H2O2、盐分添加对阳离子红GTL去除率的影响,利用紫外-可见吸收光谱变化查明阳离子红GTL在不同条件下的去除差异性,利用SEM解析铁的形态与染料去除的相关性。结果表明:pH≥5.0时超声和Fe0具有协同效应,Fe0用量2 g/L,pH=7.0,超声功率135 W,阳离子红GTL去除率达到96.07%;一定量的活性炭、H2O2、盐分添加会加速染料去除,US加速Fe0反应速度,但不改变染料降解机理,添加活性炭能够彻底降解阳离子红GTL,添加H2O2提供的氧化环境抑制苯胺类化合物生成;铁的形态及与染料的接触是影响染料去除效果的重要原因。

In this article, the combination of ultrasound and zero-valent iron was used as a means to remove cationic red GTL. The effects of pH, iron loading, ultrasonic power and addition of activated carbon, hydrogen peroxide, salt on the removal of cationic red GTL were studied. The differences of degradation pathway under various systems were investigated by UV-visible absorption spectra. Relationship between iron morphology and dye removal was analyzed by SEM. The results show that synergetic effect of the ultrasonic wave and zero-valent iron is significant when ph≥5.0. Cationic red GTL removal rate can be reached 96.07% at 2 g/L of iron loading, pH = 7.0 and 135 W of ultrasonic power. Dye removal rate is accelerated by introduction of a certain amount of activated carbon, hydrogen peroxide, salt. Iron reaction rate is accelerated by ultrasound but degradation mechanism of dye is not changed. Cationic red GTL can be degraded completely under carbon addition. Production of aniline compounds is inhibited by oxidation environment provided by hydrogen peroxide. Iron morphology and contacted with dye are the important reasons for affecting dye removal efficiency.