Phosphorus removal from aqueous solutions containing low concentration of phosphate using pyrite calcinate sorbent

Abstract

Natural pyrite was modified by calcination under nitrogen (N 2 ) atmosphere to produce a novel sorbent for removing phosphorus (P) with low concentration from aqueous solutions. The crystallinity, porous texture, magnetic susceptibility and performance in P removal of pyrite calcinates depended on calcination temperatures. The sorbent obtained at calcination temperature of 500-600°C possessed the most efficient P removal. Solution pH in the range of 3.0-9.0 and anions of chloridion (Cl -), nitrate (NO 3 )-and sulfate (SO 4 2-) had ignorable effect on P removal. The batch adsorption experiment shows that the maximum sorption capacities for P of this novel sorbent (q m ) were up to 1.61-5.36 mg P/g at adsorption temperatures of 15-35°C. Dynamic sorption and regeneration experiments were conducted in an adsorption column filled with pyrite calcined at 600°C. The study found that oxygen was an important control factor responsible for P adsorption because the oxidization of Fe 2? to Fe 3? on the surface of the sorbent followed by P being bound to a ferric hydroxide surface film was the crucial processes. The mechanism was confirmed with surface characterization techniques including field emission scanning electron microscope and X-ray photoelectron spectroscopy. This research potentially provides a cheap, abundant sorbent for P removal from the secondary effluent of municipal wastewater treatment plant.

Adsorption of nutrients using low-cost adsorbents from agricultural waste and by-products – review

“…Divya et al [63] stated that the presence of anions like Cl2, SO4 2-, NO 3and CO3 2did not show any significant influence on phosphate adsorption, whilst some cations such as Ca 2+ , Mg 2+ , Cu 2+ , Fe 2+ and Zn 2+ facilitate the process. These findings coincide with those reported by Chen et al [64]. They concluded that anions of Cl -, NO 3-, and SO4 2had a negligible effect on phosphorus adsorption by natural pyrite however mahatheva kalaruban et al [65] illustrates that nitrate removal efficiency using amine grafted corncob drastically fell in the presence of phosphate and chloride ions.…”

Green Preparation of Nanoporous Pyrrhotite by Thermal Treatment of Pyrite as an Effective Hg(Ⅱ) Adsorbent: Performance and Mechanism

“…The second region (493-531 • C) is associated with the process of ferrous sulfate decomposed to hematite and sulfur dioxide gas [23]. The third region (531-697 • C) and the endothermic peak at 676 • C corresponds to the process that the pyrite transformed to pyrrhotite by desulfuring as follows in Equation (3) [18]. Lastly, the fourth region (under 800 • C) is assigned to the conversion of monoclinic pyrrhotite to hexagonal pyrrhotite [24].…”

“…Therefore, in order to gain highly reactive products, our group developed a cost-effective method by thermally activating pyrite [15]. Thermally activated pyrrhotite as a promising adsorbent has been studied for the removal of various contaminants, such as Cu(II) [16], Pb(II) [17,18], U(VI) [19], and Hg 0 [20]. They all exhibit excellent adsorption characteristics.…”

Use of industrial by-products and natural media to adsorb nutrients, metals and organic carbon from drinking water

“…The composition of pyritic fill may be predominantly mudstone or sandstone, depending on the location in which it is quarried, so its adsorption capacity is potentially variable. However, mineral pyrite has been recognised as an adsorbent, particularly regarding P, and adsorption capacities of up to 1.6 mg PO 4 3− -P g −1 have been measured (Chen et al, 2015). It is known that P binding occurs in the presence of Ca, Al and Fe oxides (Egemose et al, 2012), which explains the results of the pyritic fill adsorption studies.…”