Comparison Of Catalytical Reaction Efficiency In Pharmaceutical Wastewater Treatment By Microwave Assisted Fenton-like Technology

The pharmaceutical wastewater was difficult to be treated by biological method for its high concentration of organic pollutants and poor biodegradability.At present,there were still many problems in the field of pharmaceutical wastewater treatment.Fe²⁺ion was replaced by other catalyst such as Fe³⁺ion.Compared with traditional Fenton technology,it was more suitable for industrial wastewater.And many micro flocs were generated by microwave irradiation,there were no need to adjust the pH value.This paper focused on the preparation of special active component,pharmaceutical wastewater treatment,etc.The main contents of this paper were shown as follows.Firstly,the basic experiment about the catalyst of Fe³⁺ion was studied and the results were obtained.?1?The TOC removal of wastewater was 63.07%,and color was removed from 50 times to 0 under optimal condition.?2?Under optimal condition,the value of BOD₅/COD was elevated from 0.25 to 0.37,and the bacteria toxicity was dramatically decreased from 5.0 Zn²⁺mg/L to 0.6 Zn²⁺mg/L.?3?Microwave assisted Fenton-like technology provided favorable conditions for the following biological treatment.Secondly,novel supported catalyst was developed by hydrothermal method and a little ammonia on the basis of incipient impregnation method.The novel supported catalyst CuO_x-CeO_x/GAC was studied by catalyst characterization,and the results were depicted as follows.?1?SEM results indicated that the catalyst prepared by novel method had the following advantages,such as uniform distribution of small particle,large amount of loading,and no aggregation phenomenon.?2?EDX results showed that the distribution of catalyst active component and additive was superior.Moreover,it had no carbonate.That was the reason for high activity of novel supported catalyst.?3?XRD spectral demonstrated that only one crystal type of CuO was detected from the catalyst.It indicates that CuO_x was more strongly repulsive to carbonate.?4?The novel supported catalyst of CuO_x-CeO_x/GAC could be reused for at least five times,indicating that it was stable enough to be recycled in the pharmaceutical wastewater treatment.Thirdly,by comparing the changes of H₂O₂ content in the Fenton-like system between microwave irradiation and mixing condition,it could be seen that microwave irradiation could significantly shorten the time of oxidation reaction.The mass transfer was much stronger than that of mixing condition.Therefore,this paper focused on the development of novel supported catalyst,and proposed a new way for treatment of pharmaceutical wastewater.The special active component was ferric hydrate oxide?or copper hydrate oxide?with no carbonate,which was the reason for the high efficiency of novel supported catalyst.In addition,it was an important discovery in the field of Fenton/Fenton-like process.Microwave assisted Fenton-like technology could degrade the pollutants,toxins,and greatly improve the biodegradability.Meanwhile,under the condition of excess hydrogen peroxide,the novel supported catalyst could be used lonely to make the TOC of the wastewater drop to a low concentration.Thus,novel supported catalysts showed specific advantages.