Modeling of radionickel sorption on MX-80 bentonite as a function of pH and ionic strength

Abstract

MX-80 bentonite was detected using acid-based titration, XRD and FTIR in detail. The sorption behavior of 63 Ni(Ⅱ) from aqueous solution to MX-80 bentonite was investigated as a function of solid content, ionic strength and pH by using batch technique. The experimental data of 63 Ni(Ⅱ) sorption on MX-80 bentonite was obtained using the diffuse layer model (DLM) with the aid of FITEQL 3.1 program. The results indicated that the sorption of 63 Ni(Ⅱ) on MX-80 bentonite was mainly dominated by surface complexation, and cation exchange also contributed partly to 63 Ni(Ⅱ) sorption at low pH values.The sorption isotherms were simulated by Langmuir and Freundlich models, and the results indicated that Freundlich isotherm model fitted the sorption data better than the Langmuir isotherm model. The results are crucial to evaluate the sorption and migration of radionickel in MX-80 bentonite.

Adsorptive Removal of Reactive Black 5 from Wastewater Using Bentonite Clay: Isotherms, Kinetics and Thermodynamics

“…Moreover, FTIR peaks at 632 nm are associated to the Al-O connection that was in a tetrahedral coordination with aluminum cations [32]. The FTIR peaks at 527 nm and 460 nm are associated to Al-O-Si and Si-O-Si bending vibrations, respectively [33,34]. Montmorillionite-22A is the main component of bentonite clay.…”

The sorption mechanisms of Th(IV) on attapulgite

“…However, the added OH  only changes the pH values in the blank system [24,25]. The potentiometric titrations of intrinsic attapulgite and blank under different ionic strengths are shown in Figure 3.…”

“…Figure 4 shows the Gran plots of the back-titration data of blank, intrinsic and activated attapulgite samples. The values of the Gran function (G) were calculated as follows [24,25]:…”

“…V at and V b are the total volumes of acid solution and of OH  added at the different titration points, respectively. The hydroxide ions added to attapulgite suspension are consumed by the following steps reflected in the Gran plots: neutrali- zation of excess H + in the suspension (before V eb1 ), reactions with the various receivers on attapulgite surfaces (between V eb1 and V eb2 ), and adjustment of the system pH (after V eb2 ) [19,25]. The acid-base titration data and fitting curve are shown in Figure 5.…”

Mesoporous silica (KIT-6) derivatized with hydroxyquinoline functionalities as a selective adsorbent of uranium(VI)

“…9, the amount of U(VI) ions adsorbed decreased as the NaNO 3 concentrations increasing from 0.01 to 0.1mol L -1 , and then remained stable when the concentration of NaNO 3 was higher than 0.1 mol L -1 . These results indicated that three kinds of materials are greatly influenced at low ionic strength but weakly influenced at a higher ionic strength [54][55][56]. This phenomenon could be explained by the fact Fig.…”