Concurrent two one‐electron transfer in the oxidation of chromium(III) complexes with trans‐1,2‐diaminocyclohexane‐N,N,N′,N′‐tetraacetate and diethylenetriaminepentaacetate ligands by periodate ion

Abstract

The kinetics of oxidation of [Cr III cdta(H 2 O)] − and [Cr III dtpa(H 2 O)] 2− (where cdta = trans-1,2-diaminocyclohexane-N,N,N ,N -tetraacetate and dtpa = diethylenetriaminepentaacetate) by periodate ion has been studied in aqueous solutions. The oxidation of these complexes was carried out in the pH range 5.52-7.44 for the [Cr III cdta(H 2 O)] − complex and the pH range 5.56-8.56 for the [Cr III dtpa(H 2 O)] 2− complex. The reaction exhibited an uncommon

Exploring Adsorption Process of Lead (II) and Chromium (VI) Ions from Aqueous Solutions on Acid Activated Carbon Prepared from Juniperus procera Leaves

“…where V is the volume of the metal solution in the flask, q e is the metal uptake capacity (mg/g), M is the dry mass of biosorbent (g), C o is the initial metal ions concentration, and C e is the metal ions concentration at the equilibrium. The overall removal efficiency (R%) of metal ions was determined using Equation (2). All experiments were carried out in duplicate and the average value was used for further calculation.…”

“…[1]. As for the chromium, Cr(VI) is reported to be more toxic than Cr(III) and severely affects human physiology [2].…”

Kinetic, isotherm and thermodynamic studies on biosorption of chromium(VI) by using activated carbon from leaves of Ficus nitida

“…When chromium(VI) accumulates at high levels, it may lead to serious problems and even be fatal when concentrations reach 0.10 mg/g of body mass [4]. Chromium(VI) is more toxic than chromium(III) and as such receives more attention.…”

Effect of Acid Extract of Leaves of Juniperus procera on Corrosion Inhibition of Carbon Steel in HCl Solutions

“…Values of ∆H * and ∆S * are calculated from slope and intercept of Figure 5 and equation 8, respectively. The negative values of entropy of activation (ΔS * ) imply that the activated complex throughout the rate-determining step is an association rather than a dissociation step [51], indicating that a decrease in disordering occurs on going from reactants to the activated complex [52,53]. The negative signs of ∆H * indicates that the corrosion process is an endothermic.…”