Catalytic ozonation of high saline petrochemical wastewater using PAC@FeIIFe2IIIO4: Optimization, mechanisms and biodegradability studies
Catalytic ozonation of high saline petrochemical wastewater using PAC@FeIIFe2IIIO4: Optimization, mechanisms and biodegradability studies
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DOI：
10.1016/j.seppur.2017.01.008
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发表时间：
2017-04-28
影响因子：
8.6
通讯作者：
Babaei, Ali Akbar
中科院分区：
文献类型：
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作者：
Ahmadi, Mehdi;Kakavandi, Babak;Babaei, Ali Akbar
本论文首次研究了磁性氧化铁炭（PAC@Fe3O4）的制备及其在臭氧氧化处理PVC和VCM高盐石化废水中的催化性能。对催化剂的结构和表面性质、操作因素的影响、生物降解性和机理进行了详细的研究。结果表明，pH值对COD去除率的影响很小，而催化剂浓度和臭氧浓度对工艺性能有显著影响。在最佳操作条件下，催化臭氧氧化120 min后，COD和TOC的去除率分别达到75.3%和50.3%。有机化合物也通过臭氧转化为中心点OH在催化剂表面和在溶液中的叔丁醇鉴定。提出了吸附、均相和非均相催化臭氧化的综合机理。PCW经PAC@Fe3O4/O-3体系处理120 min后，BOD 5/COD比值、AOS和COS指标均得到显著提高。该催化剂在5次循环后铁浸出较弱，催化活性较高，可重复使用。因此，PAC@Fe3O4/O-3工艺可有效降低PCW的COD，达到排放标准，提高可生化性，是一种有效的、有前途的PCW处理技术。(C)2017爱思唯尔B. V.保留所有权利。
This work specially focused on preparation of a magnetic catalyst, carbon impregnated by iron oxide (PAC@Fe3O4), and consider its catalytic ability for the first time in ozonation of high saline petrochemical wastewater (PCW) from PVC and VCM manufacturing industries. The structural and surface properties of the catalyst, the effect of operational factors, biodegradability and mechanisms were also studied in details. Results revealed that the influence of pH on COD removal rate was negligible, whereas process performance was significantly affected by various concentrations of catalyst and ozone. Under the optimum operational conditions, COD and TOC removal reached to 75.3 and 50.3% after 120 min catalytic ozonation, respectively. Organic compounds were also degraded through transformation of ozone into center dot OH both over catalyst surface and in the solution as identified by tert-butanol. A probable comprehensive mechanism include adsorption, homogeneous and heterogeneous catalytic ozonation was also proposed. The biodegradability of PCW was noticeably improved based on the BOD5/COD ratio, AOS and COS indices after 120 min reaction by PAC@Fe3O4/O-3 system. The catalyst indicated a weak iron leaching and high catalytic activity upon five recycling cycles, which confirms that it can be reused many times. Therefore, the PAC@Fe3O4/O-3 process was an effective and promising technique for successful PCW treatment, due to the efficient reduction of COD, achieve discharge standards and enhance biodegradability. (C) 2017 Elsevier B.V. All rights reserved.