Photocatalytic degradation of an azo dye in a tubular continuous-flow photoreactor with immobilized TiO2 on glass plates
Photocatalytic degradation of an azo dye in a tubular continuous-flow photoreactor with immobilized TiO2 on glass plates
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DOI：
10.1016/j.cej.2006.09.013
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发表时间：
2007-03-01
影响因子：
15.1
通讯作者：
Rabbani, M.
中科院分区：
文献类型：
--
作者：
Behnajady, M. A.;Modirshahla, N.;Rabbani, M.
C.I.的光催化降解酸性红 27 (AR27) 是一种酸性类阴离子单偶氮染料，在玻璃板上固定有 TiO2 的管式连续流光反应器中研究了水溶液中的情况。去除百分比是光反应器长度、体积流量和光强度的函数。去除效率随着光强度的增加而增加，但随着流速的增加而降低。通过 HPLC、UV-vis 和化学需氧量 (COD) 分析跟踪 AR27 的降解情况。这些分析的结果表明，光反应器的最终出口流被相当程度地矿化。 NH4+、NO3-、NO2- 和 SO42- 离子分别作为氮和硫杂原子的矿化产物进行分析。结果表明，SO42-离子和含氮矿化产物的最终浓度低于最终预期的化学计量值。基于当前和以前的研究结果，提出了 AR27 光催化降解的反应途径。连续模式下 AR27 脱色的动力学分析显示出伪一级反应。结果表明，拟一级反应速率常数与体积流量倒数之间存在线性关系。 (c) 2006 Elsevier B.V. 保留所有权利。
The photocatalytic degradation of C.I. Acid Red 27 (AR27), an anionic monoazo dye of acid class, in aqueous solutions was investigated in a tubular continuous-flow photoreactor with immobilized TiO2 on glass plates. The removal percent is a function of photoreactor length, volumetric flow rate and light intensity. The removal efficiency increases as the light intensity increases but it decreases when the flow rate is increased. The AR27 degradation was followed through HPLC, UV-vis and chemical oxygen demand (COD) analyses. The results of these analyses showed that the final outlet stream from the photoreactor was considerably mineralized. NH4+, NO3-, NO2- and SO42- ions were analyzed as mineralization products of nitrogen and sulfur heteroatoms, respectively. Results show that the final concentration of SO42- ions and N-containing mineralization products are less than the final expected stoichiometric values. Based on the results obtained in present and previous studies, a reaction pathway for the photocatalytic degradation of AR27 is proposed. The kinetic analysis of the decolorization of AR27 in continuous-mode shows a pseudo-first-order reaction. Results show that a linear relation exists between pseudo-first-order reaction rate constant and reciprocal of volumetric flow rate. (c) 2006 Elsevier B.V. All rights reserved.