Removal of tungsten from electroplating wastewater by acid- and heat-treated sepiolite

Abstract

In this study, the removal of tungsten from electroplating wastewater by adsorption on sepiolite has been investigated. To improve its performance, the natural sepiolite, was treated using H 2 SO 4 , followed by a heat treatment. The results obtained from the adsorption experiments showed that the acid-and heat-treated sepiolite had much higher adsorption for tungsten compared to the untreated (natural) sepiolite. The pH and temperature were important parameters in the adsorption process: the tungsten adsorption onto the acid-and heat-treated sepiolite increased at a lower pH and higher temperature, and the maximum adsorption capacity of 48.3 mg/g was obtained at pH 4.0, 55˚C, initial concentration of tungsten of 300 mg/L, and the sepiolite to liquid ratio of 0.5 g/100 mL. The acid-and heattreated sepiolite was applied to electroplating industrial wastewater containing 265 mg/L tungsten, under the conditions of pH ≤ 6, 25-55˚C, more than 98% of tungsten was removed. It was concluded that the acid-and heat-treated sepiolite is a potential adsorbent that can be commercially used to remove the residual tungsten in industrial wastewater.

Facile and Efficient Removal of Tungsten Anions Using Lysine-Promoted Precipitation for Recycling High-Purity Tungsten

“…Conventional ion-exchange , and electroplating processes are used to remove tungsten from metal scrap wastewaters. Ion exchange is an effective method for tungsten removal and is widely used.…”

A diamino based resin modified silica composite for the selective recovery of tungsten from wastewater

“…Over the last 10 years, researchers have shown successful advances in materials science for the separation of W(VI). For example, adsorbents such as phosphoric acid and poly(allylamine) modified composites, chitosan coated clay, zeolite fly ash, polyhydroxy chelating resin, hydrated oxides of Fe‐Mn cake (FMC) and acid treated sepiolite have effectively removed W(VI) from model aqueous solutions and wastewater (Table ). In continuation of the investigation on amino resins, the results obtained in the present study demonstrate the potential of DANFR‐silica composite.…”

Chlorophenol degradation in papermaking wastewater through a heterogeneous ozonation process catalyzed by Fe-Mn/sepiolite

“…This structure gives sepiolite good adsorption properties. Sepiolite can have a very high specific surface area, as much as 900 m 2 /g in theory (Wang et al 2014), which is much greater than other natural clay mineral materials. Recently, sepiolite has been studied as an effective and economical sorbent material for wastewater treatment, including the removal of dyes and pigments (Santos and Boaventura 2008;Ugurlu 2009;Bingol et al 2010), the adsorption of surfactants and pesticides (Gonzalez-Pradas et al 2005;Ozdemir et al 2007), and the removal of heavy metal ions (Kocaoba 2009;Liang et al 2013).…”