Selective removal of phosphate from wastewater using hydrated metal oxides dispersed within anionic exchange media

A novel selective hybrid cation exchanger for low-concentration ammonia nitrogen removal from natural water and secondary wastewater

“…Note that the experimental data also followed the Freundlich isotherms model (r 2 >0.90). The good fit to two models indicates that the removal mechanisms might consist of adsorption on the surface of microparticles of resin in combination with ligand exchange with the surface functional groups [15]. Generally, the value of 1/n in the Freundlich model is used to evaluate the adsorption process [31].…”

“…At low wavenumbers, a narrow peak at 630 cm -1 is associated with the Cu-O stretching vibration [29,30], suggesting the possible formation of a bond between D61 resin and the Cu-O group. It can be deduced that the microparticles on the resin surface consist of a mixture of copper oxide and hydrated copper oxide as the resin was prepared via moderate thermal treatment and a strong -OH stretching vibration was observed in Cu-HCIX resin [15,19]. Table S5.…”

“…The properties of the D61 resin were shown in Table S1 (see SI). After treatment as described previously [25], the hybrid cation exchanger was prepared according to modified procedures from DeMarco et al [15,18] (the major steps of preparation are illustrated in Fig. 2).…”

“…In recent studies, many attempts have made to produce polymeric ion exchangers containing dispersed metal oxide, namely hydrated Fe(ІІІ) oxide (HFeO), Mn(ІV) oxide(MnO 2 ) and hydrated Zr(ІV) oxide (HZrO), which is well known as a hybrid cation exchanger (HCIX) or hybrid anion exchanger (HAIX) [14][15][16]. A hybrid ion exchanger primarily contains two components: the functionalized polymeric host that comprises an ion exchanger with mechanical strength and massive surface within their pores, and hydrated metal oxide particles within the pore spaces or on the surface of the ion exchanger which have good selectivity towards ligands but lack resistance to attrition.…”

Nanoparticles of zirconium hydrophosphate framed with a weakly-acidic cation-exchange polymer

“…As an example, the inorganic nanoparticles inserted into ion exchange resins that are available commercially can be mentioned [14][15][16][17][18][19] (subclass i). The sorbents of second subclass involve nanoparticles that are distributed homogeneously in solid phase [20][21][22][23][24].…”