Optimization of Preparation of Activated Carbon from Ricinus communis Leaves by Microwave‐Assisted Zinc Chloride Chemical Activation: Competitive Adsorption of Ni²⁺ Ions from Aqueous Solution

Abstract

The preparation of activated carbon (AC) fromRicinus communisleaves was investigated in this paper. Orthogonal array experimental design method was used to optimize the preparation of AC using microwave assisted zinc chloride. Optimized parameters were radiation power of 100 W, radiation time of 8 min, concentration of zinc chloride of 30% by volume, and impregnation time of 24 h, respectively. The surface characteristics of the AC prepared under optimized conditions were examined by pHZPC, SEM-EDAX, XRD, and FTIR. Competitive adsorption of Ni2+ions onRicinus communisleaves by microwave assisted zinc chloride chemical activation (ZLRC) present in binary and ternary mixture was compared with the single metal solution. The effects of the presence of one metal ion on the adsorption of the other metal ion were investigated. The experimental results indicated that the uptake capacity of one metal ion was reduced by the presence of the other metal ion. The extent of adsorption capacity of the binary and ternary metal ions tested on ZLRC was low (48–69%) as compared to single metal ions. Comparisons with the biosorption of Ni2+ions by the biomass of ZLRC in the binary (48.98–68.41%-~Ni-Cu and 69.76–66.29%-~Ni-Cr) and ternary solution (67.32–57.07%-~Ni–Cu and Cr) could lead to the conclusion that biosorption of Ni2+ions was reduced by the influence of Cu2+and Cr3+ions. The equilibrium data of the adsorption was well fitted to the Langmuir isotherm. The adsorption process follows the pseudo-second-order kinetic model.

Preparation and Characterization of Activated Carbon from Lapsi (Choerospondias axillaris) Seed Stone by Chemical Activation with Potassium Hydroxide

“…The isotherm represents the specific relation between the concentration of adsorbate and its degree to accumulation onto adsorbent surface at constant temperature [20]. This supports the theory that the number of active sites on the both carbon surface is limited and methylene blue forms a monolayer on the surface [25]. Langmuir constant q m and adsorption capacity log K were determined from the slope and intercept of the plot are presented (Table: 2).…”

Characterization of activated Acacia nilotica seed pods for adsorption of Nickel from aqueous solution

“…The experiments were done in 250-mL flasks each containing 50 ml of different initial pHÁNaNO 3 solutions, and 0.2 g of adsorbent ANZ was added. The pH values were adjusted using 0.1 M HCl and 0.1 M NaOH (Makeswari and Santhi 2013). After stabilization, the final pH was recorded.…”

“…It has been reported that the grater the atomic weight, electronegativity, electrode potential and ionic size, the grater will be the affinity for sorption. It is clear that the electronegativity is a dominant factor for adsorption (Makeswari and Santhi 2013).…”

Adsorption of Cr(VI) ions onto Pongamia pinnata leaves carbon from aqueous solutions –A Kinetic study

“…This means that the adsorption is highly dependent on the initial concentration of Chromium ion. This is because the ratio between the surface available on the adsorbent and the concentration of metal ion in the solution phase decrease with the increase of initial concentration of the solute [12]. The results obtained from pseudo first order and second order kinetic models for Chromium (VI) ions were presented in Table 3.Concerned graphs at 305 K were shown in Figures 5 and 6.…”