Rodriguez Miriam G, Martinez Sergio A D
Departamento. de Energía, Universidad Autónoma Metropolitana-Azcapotzalco, México.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2005;40(12):2215-25. doi: 10.1080/10934520500234742.
This work aimed at studying the electrochemical reduction of the hexavalent chromium Cr(VI) by means of a tubular reactor operating under both continuous and batch regimes. It is shown that chromium (VI) reduction to chromium (III) was exerted not only by the oxidation of iron to Fe(II) released from the steel sacrifice anodes immersed in an acid solution to aid the overall process. Also, it is shown that there was an additional contribution to chromium reduction from an ancillary reaction at the cathode, where Fe(III) ions generated after the Cr(VI) reduction are again reduced to Fe(II), this being interpreted as a catalytic effect taking place. The results are presented at pH values of 1, 1.3, 1.7, and 2: it became clear that the variable affected the solubility of the species generated in solution. The initial chromium hexavalent concentration was 1000 mg L(- 1) and it was found that after treatment times ranging from 320 to 25 minutes this could reach values as low as 0.5 mg L(- 1), depending on the operating conditions.
这项工作旨在研究通过在连续和间歇模式下运行的管式反应器对六价铬Cr(VI)进行电化学还原。结果表明，将铬(VI)还原为铬(III)不仅是通过将浸泡在酸性溶液中的钢铁牺牲阳极释放出的铁氧化为Fe(II)来实现的，这有助于整个过程。此外，研究还表明，阴极的一个辅助反应对铬的还原有额外贡献，在该反应中，Cr(VI)还原后生成的Fe(III)离子再次被还原为Fe(II)，这被解释为一种催化作用。研究结果是在pH值为1、1.3、1.7和2的条件下得出的：很明显，该变量影响了溶液中生成的物质的溶解度。六价铬的初始浓度为1000 mg L(-1)，结果发现，根据操作条件，在320至25分钟的处理时间后，其浓度可降至低至0.5 mg L(-1)。
