Dye biosorption from water employing chemically modified calabrian pine cone shell as an effective biosorbent

Abstract

The feasibility of base (0.1 M NaOH) treated cone shell of Calabrian pine as an effective and inexpensive biosorbent was examined for removal of C.I. Basic Red 46 as a model azo dye from aqueous solution. Biosorption conditions selected for this study were optimized using Taguchi experimental design. The pseudo-first-order, pseudo-second-order, logistic, and intraparticle diffusion models were used for the evaluation of kinetic data. The logistic model presented the best fit to the experimental results with the most suitable statistical outcomes. The intraparticle diffusion was not the only rate-limiting step for the dye biosorption and also the other mechanism(s) may control the rate of biosorption or all of which may be operating simultaneously. Furthermore, the relationship between the kinetic parameters and the biosorption performance was investigated. The equilibrium data were analyzed using Freundlich, Langmuir, and DubininRadushkevich isotherm models. Langmuir model fitted better to the biosorption data than Freundlich model. The maximum monolayer biosorption capacity of the biosorbent for the dye was found to be 89.76 mg g 21 . Besides, when compared with the natural cone shell, the chemically modified cone shell has a greater biosorption capacity for C.I. Basic Red 46. The base modification improved the biosorption ability of the biosorbent for the dye. Dubinin-Radushkevich model and the standard Gibbs free energy change presented that the predominant mechanism of the biosorption of dye by the cone shell was likely physical biosorption. Finally, a single-stage batch biosorption system design for the dye removal was outlined based on the equilibrium data obtained.

Enhanced adsorptive removal of Safranine T from aqueous solutions by waste sea buckthorn branch powder modified with dopamine: Kinetics, equilibrium, and thermodynamics

“…Thereinto, using the natural agricultural lignocellulosic byproducts as cheaper and effective biosorbents are gaining public and technological attentions because of their unique merits that were characterized by both environmental conservation and waste recycle. For instance, cotton waste [12], cone shell of calabrian pine [13], coco-peat [14], etc., have been widely utilized to adsorptively remove dyes from wastewater.…”

Composite of biomass and lead resistent Aspergillus oryzae for highly efficient aqueous phase Pb(II) adsorption

“…The curve a1, a2, a3 in Figure 2a represent the FTIR spectra of PS, PSH, and Pb 21 -loaded PSH, respectively, the curve b1, b2, b3 in Figure 2b represent the FTIR spectra of MC, MCH and Pb 21 -loaded MCH, respectively. Broad bands around 3750-3200 cm 21 could be assigned to O-H stretching vibration and N-H stretching vibration, the broad peaks around 2950-2700 cm 21 are related to the C-H asymmetrical stretch vibration bond in CH 2 , the peaks at 1734 cm 21 correspond to the C 5 O stretching vibration of the carboxyl group, the peaks around 1700-1600 cm 21 are associated with C 5 O stretching vibration of the carboxyl group, ester group and aldehyde group, 21 can be assigned to the heterocyclic compound vibration of pyridine and furfuran [14]. Broad bands around 3750-3200 cm 21 could be assigned to O-H stretching vibration and N-H stretching vibration, the broad peaks around 2950-2700 cm 21 are related to the C-H asymmetrical stretch vibration bond in CH 2 , the peaks at 1734 cm 21 correspond to the C 5 O stretching vibration of the carboxyl group, the peaks around 1700-1600 cm 21 are associated with C 5 O stretching vibration of the carboxyl group, ester group and aldehyde group, 21 can be assigned to the heterocyclic compound vibration of pyridine and furfuran [14].…”

“…The effect of the initial pH on different biosorbent removal for Pb 21 ions were shown in Figure 4. On the other hand, at low pH, the large amount of H 1 compete for active adsorption sites with Pb 21 ions, which also led to the decline of the removal rate of Pb 21 [19][20][21]. The removal rate reached its peak when the initial pH range was 5.5-6.0, and remained virtually unchanged when the pH was above a value of 4.0.…”

“…All the adsorption experiments were carried out in 250 mL sealed conical flasks, containing 50 mL of solution with required Pb 21 concentrations. The flasks were shaken at 258C at a speed of 125 rpm min 21 . For the pH effect experiments, the initial pH of the Pb 21 solutions was adjusted from 2 to 6 with the certain initial Pb 21 concentration (100 mgÁL 21 ) and biosorbent concentration (4 gÁL 21 ) and kept agitating for 1080 min.…”

“…Glass wool (height 5 10 mm) was placed inside the column to obtain a uniform inlet flow into the column. The Pb 21 solution (100 mg L 21 ) was pumped through the column using a peristaltic pump at a flow rate of 3.6 mL min 21 . Samples from the column effluent were collected at regular intervals and analyzed by AAS.…”