A two-step strategy for high-efficiency fluorescent dye removal from wastewater

Abstract

Conventional circulating activated sludge techniques (CASS) are time consuming (72 h) and energy intensive, all of which greatly limits their use. Although advanced oxidation techniques (e.g., photocatalysis, photoelectrocatalysis UV/•OH, and Electro-Fenton) can reduce the treatment time by several hours, the slow generation and fast coupling of electron and hole make the low degradation efficiency. In this work, an intact route using a two-step strategy is developed to eliminate organic dyes from wastewater in only a few minutes. The electron and hole exhibit "fast generation and slow coupling" by using the new technique via electrolytic discharge plasma (EDP) combined with a core-shell structure Au@SiO 2 nanocatalyst for [Rhodamine (RhB)/Eosin yellowish (EY)] dyes degradation in wastewater. Results demonstrate that the synergy of EDP and Au@SiO 2 nanocatalyst enhances degradation kinetics, and it is effective in degrading different concentrations of RhB and EY dyes in the range of 50-1.5 mg/L. Then, the Au@SiO 2 nanocatalyst (over 99%) and carbon impurities are filtered by a porous nanocomposite ultrafiltration membrane. Favorable contributions of the two-step strategy are further ascertained based on chemical oxygen demand (COD) and relative removal efficiency. This two-step strategy provides an unprecedented rapid approach for industrial wastewater treatment.npj Clean Water (2019) 2:16 ; https://doi.

Physico‐chemical processes

“…Low molecular weight carboxylic acids were remained in the treated wastewater. Gui et al (2019) demonstrated that electrolytic discharge plasma (EDP) combined with a core-shell structure Au@SiO 2 nanocatalyst was effective in dye degradation in wastewater within several minutes. Degradation kinetics were enhanced by the synergy of EDP and Au@SiO 2 nanocatalyst.…”

Preparation of magnetic Co–Fe layered double hydroxides and its adsorption properties for the removal of methyl orange

“…2 Among them, azo dyes are widely applied in the textile, printing, leather, food, and cosmetic industries and are the most used synthetic dyes. [3][4][5][6] Currently, the commonly used methods for azo dye wastewater treatment include electrolytic precipitation, 7,8 electrodialysis, 9 biochemical methods, 10,11 and adsorption methods. 12 Among these, the adsorption method is widely used because of its high efficiency, low consumption, low cost, and simple operation.…”

Easy fabrication of l-glutamic acid/ZnS composites for efficient photo-catalytic and supercapacitor performance

“…The world is experiencing growing demand for energy and unavailability of freshwater due to fast industrialization, suburbanization, mismanagement and population growth. 1,2 The quality of drinking water is lowered because of the existence of poisonous organic pollutants, which also have an impact on the health of humans and the aquatic environment. In order to mitigate the effects of this issue, a number of different approaches have been implemented, like removing organic dyes from wastewater.…”