Machado Tiele Caprioli, Lansarin Marla Azário
Chemical Engineering Department, Federal University of Rio Grande do Sul Rua Luiz Englert s/n-CEP: 90040-040, Porto Alegre, RS, Brazil E-mail:
Water Sci Technol. 2016 Oct;74(7):1698-1705. doi: 10.2166/wst.2016.344.
The hexavalent chromium, Cr(VI), which is generated in the electroplating process, is toxic to most organisms and potentially harmful to human health. The method generally used for remediation of wastewater containing Cr(VI) employs chemicals with high toxicity. This work proposes an alternative technology for the treatment of these wastewaters, based on photochemical reduction of Cr(VI) by alcohols under radiation, which is environmentally sustainable and economically viable. Initially, a batch reactor in laboratory scale was used to determine the best experimental conditions and its specific reaction rate was calculated. Based on these results, a tubular reactor (artificial radiation and sunlight) was designed and built in semi-pilot scale. Tests were carried out with real wastewater from an electroplating industry containing Cr(VI). Tests conducted under sunlight showed a higher total Cr(VI) reduction than the tests with artificial radiation. The remediation of Cr(VI) from wastewater was 86.7% after 6 h of reaction under sunlight, indicating the high efficiency of the developed process.
电镀过程中产生的六价铬（Cr(VI)）对大多数生物有毒，对人体健康有潜在危害。通常用于处理含Cr(VI)废水的方法使用的是高毒性化学品。本研究提出了一种处理这些废水的替代技术，该技术基于醇类在辐射下对Cr(VI)的光化学还原，具有环境可持续性且经济可行。首先，使用实验室规模的间歇式反应器来确定最佳实验条件，并计算其特定反应速率。基于这些结果，设计并建造了半中试规模的管式反应器（人工辐射和阳光）。对来自电镀行业含Cr(VI)的实际废水进行了测试。在阳光下进行的测试显示，总Cr(VI)还原率高于人工辐射测试。在阳光下反应6小时后，废水中Cr(VI)的去除率为86.7%，表明所开发工艺的高效性。
