Synthesis and characterization of cobalt ferrocyanides loaded on organic anion exchanger

Colloid stable sorbents for cesium removal: Preparation and application of latex particles functionalized with transition metals ferrocyanides

“…Although different types of ferrocyanides were reported as efficient sorption media for cesium uptake [1][2][3][4][5], there are differences in sorption capacities and distribution coefficients in dependence on the type of the transition metal cation used [1,[13][14][15][16] and composition of the ferrocyanide -simple or mixed [4]. To optimize the composition of colloid-stable nanosized sorbents we have immoblized into the polymeric matrix of KE copper, nickel, and Isotherms of cesium sorption on KE latexes modified with all types of ferrocyanides were of the high affinity type with little differences in sorption capacities in dependence on the cation type used (Fig.…”

“…particle size, is known in literature [1,19]. Recently, Valsala et al [4] reported that cobalt ferrocyanides loaded in the ion-exchangers had higher sorption capacities than pure cobalt ferrocyanide precipitated outside, since in the former case the particle growth was limited by the pore size of the resin. The possibility of this scenario is indirectly confirmed by notably lower colloidal stability of KE-Me 2 [Fe(CN) 6 ] sorbents with ferrocyanide content of 4 × 10 −5 mol/g of latex compared to those containing only 2 × 10 −5 mol ferrocyanide/g.…”

“…Usually, loading ferrocyanide fines into the mechanically stable matrix results in slower kinetics due to the diffusion limitations [1,4]. Valsala et al [4] compared the kinetics of cesium uptake by ferrocyanides precipitated and loaded on anion-exchanger and found that in the latter case cesium uptake was retarded despite smaller size and higher surface area of ferrocyanides formed in the resin pores. However, Fig.…”

“…Preparation and application of solid ferrocyanides for cesium removal have been extensively investigated over the last 50 years [1][2][3][4][5]. Usually ferrocyanides are obtained as fines, which have superior sorption properties due to high surface area and fast kinetics, but are notoriously difficult to handle in the process of liquid radioactive waste (LRW) treatment [1,4].…”

“…Usually ferrocyanides are obtained as fines, which have superior sorption properties due to high surface area and fast kinetics, but are notoriously difficult to handle in the process of liquid radioactive waste (LRW) treatment [1,4]. To overcome this disadvantage, numerous efforts have been undertaken to obtain mechanically stable granular forms of ferrocyanides for column applications [1,3,4], however, often at the expense of sorption capacity loss and much slower kinetics of cesium removal [1].…”