Adsorption Characteristics of Hair Dyes Removal from Aqueous Solution onto Oak Cupules Powder Coated with ZnO

Abstract

Three hair dyes of Arianor madder red 306003 (R), Arian or Straw Yellow 306005 (Y), and Arianor ebony 306020 (E) were removed from an aqueous solution in a batch mode using a powder of oak cupules coated with ZnO (COZ). The COZ-adsorbent material was characterized in terms of XRD, FT-IR, and SEM analysis. The best conditions for the uptake of hair dyes by COZ were investigated. For Y dye, the best uptake was estimated on 0.06g of COZ at 7.0 pH for 150 min. The E dye uptake requires 120 min on 0.05g of COZ at 9.0 pH. For E hair dye, kinetic data revealed a pseudo-first-order model for E hair dye and a pseudo-second-order model for R and Y. Equilibrium data exhibited consistency with the Langmuir isotherm model for the adsorption of E dye onto COZ, and the Freundlich isotherm model for the adsorption of R and Y hair dyes onto COZ. Isotherms models of D-R and Temkin were also examined. The thermodynamic parameters (−ve ∆G and +ve ∆H and ∆S) demonstrated that the removal of hair dyes by COZ is spontaneous, endothermic, and feasible. The adsorption capacity of COZ for R, Y, and E uptake was found to be 55.5, 52.6, and 135.1 mg·g−1, respectively. Furthermore, COZ reusability was demonstrated after five cycles of regeneration, with a negligible decline in adsorption extent (13.08%, 13.85, and 10.20% for R, Y, and E, respectively) in comparison to its initial capacity.

Sonicating for the Uptake of Paracetamol from Solution by Activated Carbon from Oak: Kinetics, Thermodynamics, and Isotherms

“…Isothermal models Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich (D-R) isothermal models were employed to elucidate the adsorption mechanism of PA onto ACO. Equations (6), (7), (8), and (9) represent the nonlinear form of the Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich (D-R) isotherm models, respectively [10, 11]. (6) q e = k L q m C e 1 + k L C e , (7) q e = K F C e 1 / n , (8) q e = B l n A C e , (9) q e = q m e − B D ε 2 . …”

“…A UV-6100 PC double-beam spectrophotometer was used to investigate the PA concentrations at a wavelength of 244 nm. The adsorbed amount of PA onto the ACO, q e (mg. g -1 ), was calculated using Equation (1) [10, 11]. (1) q e = C i − C eq V m . …”

Magnetic Luffa-Leaf-Derived Hierarchical Porous Biochar for Efficient Removal of Rhodamine B and Tetracycline Hydrochloride

“…Adsorption kinetics describe the changes in the adsorbent and model adsorbent with contact time [ 42 ]. The influence of contact time on the adsorption capacity of RhB and TH by LLB-MB and LLB-Mb@Fe 3 O 4 was explored at different initial solution concentrations at 303 K, and the results are shown in Figure 6 and Figure 7 .…”

“…Although the theoretical adsorption capacities ( Q e.cat ) calculated from the model (904.1, 1356.3, and 1571.5 mg/g of LLB-MB for RhB; 988.3, 1415.9, and 1670.0 mg/g of LLB-MB@Fe 3 O 4 for RhB; 798.3, 1237.1, and 1570.1 mg/g of LLB-MB for TH; and 874.8, 1413.7, and 1680.4 mg/g of LLB-MB@Fe 3 O 4 for TH) were slightly lower than the experimental Q e (941.6, 1386.6, and 1606.5 mg/g of LLB-MB for RhB; 998.1, 1502.2, and 1698.2 mg/g of LLB-MB@Fe 3 O 4 for RhB; 831.4, 1298.0, and 1602.4 mg/g of LLB-MB for TH; and 896.1, 1453.5, and 1749.9 mg/g of LLB-MB@Fe 3 O 4 for TH), they still indicated that the PFK model may be applicable to the adsorption process in some aspects. At the same time, it also showed that the adsorption capacity will increase with the initial concentration increasing to some extent [ 42 , 43 ]. While Ho-McKay’s PSK model was used to fit the data, the correlation coefficients ( R 2 ) of LLB-MB and LLB-MB@Fe 3 O 4 ranged from 0.9987 to 0.9998 and from 0.9964 to 0.9998 for RhB and ranged from 0.9989 to 0.9998 and from 0.9983 to 0.9994 for TH, which showed the applicability of PSK in the adsorption process.…”

“…While Ho-McKay’s PSK model was used to fit the data, the correlation coefficients ( R 2 ) of LLB-MB and LLB-MB@Fe 3 O 4 ranged from 0.9987 to 0.9998 and from 0.9964 to 0.9998 for RhB and ranged from 0.9989 to 0.9998 and from 0.9983 to 0.9994 for TH, which showed the applicability of PSK in the adsorption process. In addition, the adsorption processes of LLB-MB and LLB-MB@Fe 3 O 4 for RhB and TH may be chemical reactions, and the adsorption behaviors of chemisorption bonds formed by transfer, exchange, or sharing can control the adsorption rate and affect the adsorption process of the adsorbents [ 28 , 42 , 43 ].…”