Phosphate Removal from Digested Sludge Supernatant Using Modified Fly Ash

Abstract

The removal of phosphate in digested sludge supernatant by modified coal fly ash was investigated in this study. Modification of the fly ash by the addition of sulfuric acid could significantly enhance its immobilization ability. The experimental results also showed that adsorption of phosphate by the modified fly ash was rapid with the removal percentage of phosphate reaching an equilibrium of 98.62% in less than 5 minutes. The optimum pH for phosphate removal was 9 and the removal percentage increased with increasing adsorbent dosage. The effect of temperature on phosphate removal efficiency was not significant from 20 to 40 °C. X‐ray diffraction and scanning electron microscope analyses showed that phosphate formed an amorphous precipitate with water‐soluble calcium, aluminum, and iron ions in the modified fly ash.

Phosphorus recovery from wastewater using pyridine‐based ion‐exchange resins: Role of impregnated iron oxide nanoparticles and preloaded Lewis acid (Cu2+)

“…Sorption‐based processes have shown promise in removing P from wastewater. Materials used as a P sorbent include fly ash (Xu et al, 2012), tantalum hydroxide (Yu et al, 2012), iron‐based filter (Allred & Racharaks, 2014), dolomite‐alginate composite beads (Huang et al, 2019), palygorskite (Fangqun et al, 2011), activated alumina (Tan et al, 2019), plaster of paris and hydrogel beads containing alumina particles (Malicevic et al, 2020), calcium‐rich rocks (Lamont et al, 2019), and zirconium oxide (Lin et al, 2017). Most metal oxide particles lack the mechanical strength and abrasion resistance properties for prolonged operation in fixed‐bed units (Blaney et al, 2007).…”

Simultaneous Removal of NH4+ and PO43‐ at Low Concentrations from Aqueous Solution by Modified Converter Slag

“…Among all these processes, adsorption is one of the most popular and economically feasible alternatives (Oguz, 2005;Xue et al, 2009). The search to find low-cost, effective, and easily available adsorbents for wastewater treatment has been widely investigated during recent years, with investigations including such materials as fly ash (Xu et al, 2012), wollastonite (Gustafsson et al, 2008), palygorskite (Gan et al, 2011), and agricultural waste (Yue et al, 2010) .…”