Research on the Degradation of Oxacillin in Water by Strong Ionization Discharge

The degradation of oxacillin in aqueous solution by strong ionization dielectric barrier discharge (DBD) was explored. The effects of input voltage, initial pH, initial concentration of solution and hydroxyl (·OH) inhibitor on the removal efficiency of OXA were investigated. The results showed that the removal efficiency of OXA with initial concentration of 20mg/L reached 91.5% under the optimal treatment conditions of 3.8 kV and 7.3 pH. With the higher voltage and the lower initial concentration, the removal effect was better. The pH of the solution has little effect on the removal efficiency, and the removal effect is the best in neutral aqueous solution. The inhibition effect of TBA was stronger than that of CO32- and HCO3-. Moreover, ·OH was the main active substance in the process of strong ionization discharge, which played a major role in the removal of OXA. In addition, two main by-products were identified, the transformation pathways including hydroxylation (+16 Da), decarboxylation (-44 Da) were observed. This study provided a theoretical basis for the effective removal of antibiotics in water by strong ionization discharge.

Removal of Alizarin Red Dye Using Strong Ionization Discharge Technology

The degradation of Alizarin red dye (Anthraquinone) was investigated using a novel technique of strong ionization discharge to generate high oxidation active species from oxygen. Under the optimum conditions, AR dye was almost removed with degradation rate reaching 95%, by radicals such as •OH and O3 generated within the strong ionization discharge reactor. The intermediate products were analyzed by ultraviolet (UV) spectroscopy, total organic carbon (TOC) analysis, liquid chromatography-mass spectrometry (LC-MS) and ion chromatography (IC) to validate the degradation efficiency of the strong ionization discharge for AR dye and to deduce its possible decomposition pathway. Finally, It has been confirmed that the sulfur element on AR molecule results into sulfate, an environmentally friendly substance. This work shows that the strong ionization discharge can efficiently be used for the degradation of Anthraquinone dyes as well as other extensively used textile dyes.

Study of Removing Bacteria and Microcystis aeruginosa by Hydroxyl Radical

The 1.5t/h algae and bacteria wastewater with high concentration was treated by hydroxyl radical (OH) produced by a strong ionization discharge. In this paper, the feasibility of kill bacteria and alga by OH was investigated, and effects of OH concentration, treatment time and pollution initial concentration on degrading microorganisms by OH were investigated in detail. The results indicated that the treatment process was effective in the degradation of the bacteria and alga at the initial pH value of 7.1, OH dosage of 2.33mg/L, the initial microcystis aeruginosa concentration of 106/mL and the initial bacterial dosage of 106cfu/mL, the bacteria and alga degradation rate reached 99.99% at 303K after 15min treatment. The results provided a theoretical basis for the OH treatment of microbial contamination in drinking water in large-scale.