Influence of sulfate and nitrate uptake from aqueous solutions on surface exchange in Purolite A-520E resin

Abstract

Removal of nitrate anions from aqueous solutions is the principal goal of many studies concerning water treatment. The ion exchanger capacity to remove nitrate from water was investigated using commercial type A-520E anion exchange resins. The nitrate and sulfate ion exchanger capacity, in static conditions, depends on the concentration of ions and on the pH value of the aqueous solution. The local structural environment exchanged on A-520E has been investigated by scanning electron microscopy (SEM), energy-dispersive Xray analysis (EDX) and 2D and 3D atomic force microscopy (AFM). All images of the ion exchanger were obtained before and after contact with solutions that contain NO 3 À and SO 4 2À separately as well as mixtures of both.

Sulfate Removal from Water by Ion Exchange Method Using Purolite A200 Resin

“…It was determined that an increase in the pH value in the range of 3.9 to 8.2 caused a decrease in the sorption capacity for nitrate and sulfate ions from the aqueous solution. Therefore, they observed that polymer a-520e is very good for removing nitrate anions from aqueous solutions due to its high selectivity towards nitrate ions (Stefan et al, 2014).…”

Hybrid process for the purification of water contaminated with nitrites: Ion exchange plus catalytic reduction

“…No reports have been found about nitrite removal using monometallic catalysts supported on anionic resins. On the other hand, the effect of competing ions such as sulfates, chlorides and bicarbonates on the exchange capacity and catalytic activity of the resins, were addressed only in few studies [20][21][22][23], in spite of being a key issue in order to properly determine the real catalytic behavior [24].…”

Study of Precipitates from Mine Water after Defrosting and Oxidation

“…Upon exposure to oxidizing conditions some sulphide minerals are oxidized in the presence of water and oxygen to form highly acidic, sulphate-rich wastewaters. Acidity levels, and metal composition and concentration depend on the type and amount of sulphide mineral and the presence or absence of alkaline materials [2,3]. Iron sulphides common in coal regions are predominately pyrite and marcasite (FeS 2 ), but other metals may be combined with sulphide in the form of chalcopyrite (CuFeS 2 ), covellite (CuS), and arsenopyrite (FeAsS) [4].…”