Adsorption of Cs ions using a temperature-responsive polymer/magnetite/zeolite composite adsorbent and separation of the adsorbent from water using high-gradient magnetic separation

An adsorption agent based on chitosan–zeolite composite: environmental and radioactive liquid waste remediation

“…It is observed in Table 4 that the material studied in this work removed more Cs + , in percentage terms, in comparison with other works. In terms of the adsorption capacity, the composite reaches values close to some works present in this table, in some cases, such as that by Nakamura et al 45 and Eljamal et al , 51 who used magnetic zeolites to prepare the composites. It indicates the potential of this composite for caesium removal.…”

“…Kinetic adsorption modelling was used to mathematically describe the adsorption of caesium onto the chitosan–zeolite composites. Two non-linear kinetic models were applied to our experimental data, the pseudo-first order (PFO) 44,45 and the pseudo-second order (PSO) 46 The kinetic equations used were: q t = q e (1 − exp (− k 1 t ) )where t is the contact time (min), q t is the amount of the adsorbate adsorbed at the time (mg g −1 ), q e is the equilibrium adsorption capacity (mg g −1 ), k 1 is the pseudo-first order rate constant (min −1 ) and k 2 is the pseudo-second order rate constant (g mg −1 min −1 ).…”

Smart Adsorbents for Aquatic Environmental Remediation

“…Compared to magnetite/ zeolite composite and zeolite adsorbents, the Cs + uptake rate of PMZ was significantly higher, although the amount of Cs + adsorbed was almost similar for the three composite adsorbents, as depicted in Figure 1C. [95] The hydrophobic nature of the PNIPAM above the LCST (32 °C) resulted in the aggregation and flocculation of PMZ particles, thereby assisting in the removal of the adsorbed Cs + from solution. [95] In another study, a thermo-stimuli-responsive adsorbent (TRP@MS) incorporated thermo-responsive PNIPAM into the pores of a mesoporous silica (MS) matrix.…”

“…[91,92] Above its LCST, the flocs are formed due to the hydrophobicity, allows the contaminants to be precipitated from solution. [93][94][95] PNIPAM's change in hydrophilic/ hydrophobic properties and varying binding abilities with its surface allows adsorption and desorption to be conducted using temperature as a controllable trigger. [87,96,97] The hydrophilic/hydrophobic reversible thermoresponsive characteristic of PNIPAM makes it a smart adsorbent for removal of toxic pollutants such as organic compounds and metal ions.…”

“…[95] The hydrophobic nature of the PNIPAM above the LCST (32 °C) resulted in the aggregation and flocculation of PMZ particles, thereby assisting in the removal of the adsorbed Cs + from solution. [95] In another study, a thermo-stimuli-responsive adsorbent (TRP@MS) incorporated thermo-responsive PNIPAM into the pores of a mesoporous silica (MS) matrix. [99] Therein, maximum coomassie brilliant blue (CBB) (23.8 mg g −1 ) and MB (22.5 mg g −1 ) uptake by the TRP@MS was observed above the LCST (>45 °C).…”